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Guo Q, Su J, Liao Y, Yu Y, Luo L, Weng X, Zhang W, Hu Z, Wang H, Beattie GA, Ma J. An atypical 3-ketoacyl ACP synthase III required for acyl homoserine lactone synthesis in Pseudomonas syringae pv. syringae B728a. Appl Environ Microbiol 2024; 90:e0225623. [PMID: 38415624 PMCID: PMC10952384 DOI: 10.1128/aem.02256-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 02/04/2024] [Indexed: 02/29/2024] Open
Abstract
The last step of the initiation phase of fatty acid biosynthesis in most bacteria is catalyzed by the 3-ketoacyl-acyl carrier protein (ACP) synthase III (FabH). Pseudomonas syringae pv. syringae strain B728a encodes two FabH homologs, Psyr_3467 and Psyr_3830, which we designated PssFabH1 and PssFabH2, respectively. Here, we explored the roles of these two 3-ketoacyl-ACP synthase (KAS) III proteins. We found that PssFabH1 is similar to the Escherichia coli FabH in using acetyl-acetyl-coenzyme A (CoA ) as a substrate in vitro, whereas PssFabH2 uses acyl-CoAs (C4-C10) or acyl-ACPs (C6-C10). Mutant analysis showed that neither KAS III protein is essential for the de novo fatty acid synthesis and cell growth. Loss of PssFabH1 reduced the production of an acyl homoserine lactone (AHL) quorum-sensing signal, and this production was partially restored by overexpressing FabH homologs from other bacteria. AHL production was also restored by inhibiting fatty acid elongation and providing exogenous butyric acid. Deletion of PssFabH1 supports the redirection of acyl-ACP toward biosurfactant synthesis, which in turn enhances swarming motility. Our study revealed that PssFabH1 is an atypical KAS III protein that represents a new KAS III clade that functions in providing a critical fatty acid precursor, butyryl-ACP, for AHL synthesis.IMPORTANCEAcyl homoserine lactones (AHLs) are important quorum-sensing compounds in Gram-negative bacteria. Although their formation requires acylated acyl carrier proteins (ACPs), how the acylated intermediate is shunted from cellular fatty acid synthesis to AHL synthesis is not known. Here, we provide in vivo evidence that Pseudomonas syringae strain B728a uses the enzyme PssFabH1 to provide the critical fatty acid precursor butyryl-ACP for AHL synthesis. Loss of PssFabH1 reduces the diversion of butyryl-ACP to AHL, enabling the accumulation of acyl-ACP for synthesis of biosurfactants that contribute to bacterial swarming motility. We report that PssFabH1 and PssFabH2 each encode a 3-ketoacyl-acyl carrier protein synthase (KAS) III in P. syringae B728a. Whereas PssFabH2 is able to function in redirecting intermediates from β-oxidation to fatty acid synthesis, PssFabH1 is an atypical KAS III protein that represents a new KAS III clade based on its sequence, non-involvement in cell growth, and novel role in AHL synthesis.
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Affiliation(s)
- Qiaoqiao Guo
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
| | - Jingtong Su
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
| | - Yuling Liao
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
| | - Yin Yu
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
| | - Lizhen Luo
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
| | - Xiaoshan Weng
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
| | - Wenbin Zhang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
| | - Zhe Hu
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
| | - Haihong Wang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
| | - Gwyn A. Beattie
- Department of Plant Pathology, Entomology and Microbiology, Iowa State University, Ames, Iowa, USA
| | - Jincheng Ma
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China
- Department of Plant Pathology, Entomology and Microbiology, Iowa State University, Ames, Iowa, USA
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Guo Q, Zhong C, Dong H, Cronan JE, Wang H. Diversity in fatty acid elongation enzymes: The FabB long-chain β-ketoacyl-ACP synthase I initiates fatty acid synthesis in Pseudomonas putida F1. J Biol Chem 2024; 300:105600. [PMID: 38335573 PMCID: PMC10869286 DOI: 10.1016/j.jbc.2023.105600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 12/11/2023] [Accepted: 12/13/2023] [Indexed: 02/12/2024] Open
Abstract
The condensation of acetyl-CoA with malonyl-acyl carrier protein (ACP) by β-ketoacyl-ACP synthase III (KAS III, FabH) and decarboxylation of malonyl-ACP by malonyl-ACP decarboxylase are the two pathways that initiate bacterial fatty acid synthesis (FAS) in Escherichia coli. In addition to these two routes, we report that Pseudomonas putida F1 β-ketoacyl-ACP synthase I (FabB), in addition to playing a key role in fatty acid elongation, also initiates FAS in vivo. We report that although two P. putida F1 fabH genes (PpfabH1 and PpfabH2) both encode functional KAS III enzymes, neither is essential for growth. PpFabH1 is a canonical KAS III similar to E. coli FabH whereas PpFabH2 catalyzes condensation of malonyl-ACP with short- and medium-chain length acyl-CoAs. Since these two KAS III enzymes are not essential for FAS in P. putida F1, we sought the P. putida initiation enzyme and unexpectedly found that it was FabB, the elongation enzyme of the oxygen-independent unsaturated fatty acid pathway. P. putida FabB decarboxylates malonyl-ACP and condenses the acetyl-ACP product with malonyl-ACP for initiation of FAS. These data show that P. putida FabB, unlike the paradigm E. coli FabB, can catalyze the initiation reaction in FAS.
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Affiliation(s)
- Qiaoqiao Guo
- National Key Laboratory of Green Pesticide, Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou, China; Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Canyao Zhong
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Huijuan Dong
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - John E Cronan
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA; Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
| | - Haihong Wang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China.
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Duan Y, Yu J, Chen M, Lu Q, Ning F, Gan X, Liu H, Ye Y, Lu S, Lash GE. Knockdown of heat shock protein family D member 1 (HSPD1) promotes proliferation and migration of ovarian cancer cells via disrupting the stability of mitochondrial 3-oxoacyl-ACP synthase (OXSM). J Ovarian Res 2023; 16:81. [PMID: 37087461 PMCID: PMC10122320 DOI: 10.1186/s13048-023-01156-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 04/06/2023] [Indexed: 04/24/2023] Open
Abstract
BACKGROUND Heat shock protein 60 (HSP60) is essential for the folding and assembly of newly imported proteins to the mitochondria. HSP60 is overexpressed in most types of cancer, but its association with ovarian cancer is still in dispute. SKOV3 and OVCAR3 were used as experimental models after comparing the expression level of mitochondrial HSP60 in a normal human ovarian epithelial cell line and four ovarian cancer cell lines. RESULTS Low HSPD1 (Heat Shock Protein Family D (HSP60) Member 1) expression was associated with unfavorable prognosis in ovarian cancer patients. Knockdown of HSPD1 significantly promoted the proliferation and migration of ovarian cancer cells. The differentially expressed proteins after HSPD1 knockdown were enriched in the lipoic acid (LA) biosynthesis and metabolism pathway, in which mitochondrial 3-oxoacyl-ACP synthase (OXSM) was the most downregulated protein and responsible for lipoic acid synthesis. HSP60 interacted with OXSM and overexpression of OXSM or LA treatment could reverse proliferation promotion mediated by HSPD1 knockdown. CONCLUSIONS HSP60 interacted with OXSM and maintained its stability. Knockdown of HSPD1 could promote the proliferation and migration of SKOV3 and OVCAR3 via lowering the protein level of OXSM and LA synthesis.
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Affiliation(s)
- Yaoyun Duan
- Division of Uterine Vascular Biology, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 510623, Guangzhou, China
| | - Juan Yu
- Division of Uterine Vascular Biology, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 510623, Guangzhou, China
| | - Miaojuan Chen
- Division of Uterine Vascular Biology, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 510623, Guangzhou, China
| | - Qinsheng Lu
- Division of Uterine Vascular Biology, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 510623, Guangzhou, China
| | - Fen Ning
- Division of Uterine Vascular Biology, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 510623, Guangzhou, China
| | - Xiaowen Gan
- Division of Uterine Vascular Biology, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 510623, Guangzhou, China
| | - Hanbo Liu
- School of Medicine, South China University of Technology, Guangzhou, China
| | - Yixin Ye
- Division of Uterine Vascular Biology, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 510623, Guangzhou, China
| | - Shenjiao Lu
- Division of Uterine Vascular Biology, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 510623, Guangzhou, China
| | - Gendie E Lash
- Division of Uterine Vascular Biology, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, 510623, Guangzhou, China.
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Sun J, Zhang CP, Chen CH, Guo XM, Liu CS, Zhou Y, Hu FL. Design, Synthesis and Molecular Docking of 1,3,4-Oxadiazole-2(3H)-thione Derivatives Containing 1,4-Benzodioxane Skeleton as Potential FabH Inhibitors. Chem Biodivers 2023; 20:e202201060. [PMID: 36579401 DOI: 10.1002/cbdv.202201060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/24/2022] [Accepted: 12/27/2022] [Indexed: 12/30/2022]
Abstract
Fatty acid biosynthesis is essential for bacterial survival. Of these promising targets, β-ketoacyl-acyl carrier protein (ACP) synthase III (FabH) is the most attractive target. A series of novel 1,3,4-oxadiazole-2(3H)-thione derivatives containing 1,4-benzodioxane skeleton targeting FabH were designed and synthesized. These compounds were determined by 1 H-NMR, 13 C-NMR, MS and further confirmed by crystallographic diffraction study for compound 7m and 7n. Most of the compounds exhibited good inhibitory activity against bacteria by computer-assisted screening, antibacterial activity test and E. coli FabH inhibitory activity test, wherein compounds 7e and 7q exhibited the most significant inhibitory activities. Besides, compound 7q showed the best E. coli FabH inhibitory activity (IC50 =2.45 μΜ). Computational docking studies also showed that compound 7q interacts with FabH critical residues in the active site.
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Affiliation(s)
- Juan Sun
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, P. R. China
- School of Biological & Chemical Engineering, Zhejiang University of Science & Technology, Hangzhou, 310023, P. R. China
| | - Cui-Ping Zhang
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Chong-Hao Chen
- School of Biological & Chemical Engineering, Zhejiang University of Science & Technology, Hangzhou, 310023, P. R. China
| | - Xiao-Meng Guo
- School of Biological & Chemical Engineering, Zhejiang University of Science & Technology, Hangzhou, 310023, P. R. China
| | - Cai-Shi Liu
- School of Biological & Chemical Engineering, Zhejiang University of Science & Technology, Hangzhou, 310023, P. R. China
| | - Yang Zhou
- Zhejiang Engineering Research Center for Biomedical Materials, Cixi Institute of Biomedical Engineering, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315300, China
| | - Fu-Liang Hu
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, P. R. China
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Ma S, Jia R, Li X, Wang W, Jin L, Zhang X, Yu H, Yang J, Dong L, Zhang L, Dong J. Herbicidal Active Compound Ferulic Acid Ethyl Ester Affects Fatty Acid Synthesis by Targeting the 3-Ketoacyl-Acyl Carrier Protein Synthase I (KAS I). J Agric Food Chem 2023; 71:276-287. [PMID: 36588523 DOI: 10.1021/acs.jafc.2c07214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Exploring new herbicide targets based on natural product derivatives is an important research aspect for the generation of innovative pesticides. Ferulic acid ethyl ester (FAEE), a natural product derivative from ferulic acid, has significant herbicidal activity mainly by inhibiting the normal growth of weed seedling roots. However, the FAEE target protein underlying its herbicidal activity has not been identified. In this study, we synthesized an FAEE probe to locate its site of action. We discovered that FAEE entry point was via the root tips. Fourteen major binding proteins were identified using Drug affinity responsive target stability (DARTS) combined with LC-MS/MS, which included 3-ketoacyl-acyl carrier protein synthase I (KAS I) and phenylalanine ammonia-lyase I (PAL I). The KAS I and PAL I proteins/genes expression was changed significantly after exposure to FAEE, as evidenced by combined transcriptomic and proteomic analysis. A molecular docking assay indicated that KAS I and FAEE had a strong binding ability. Combined with previous studies on FAEE mechanism of action, and based on our results, we conclude that FAEE targeting KAS I lead to the blockage of the fatty acid synthesis pathway and result in plant death.
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Affiliation(s)
- Shujie Ma
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Ran Jia
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Xin Li
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Wen Wang
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Liyu Jin
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Xinxin Zhang
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Hualong Yu
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Juan Yang
- College of Agronomy and Biotechnology, Hebei Normal University of Science & Technology, Qinhuangdao 066000, China
| | - Lili Dong
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Lihui Zhang
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Jingao Dong
- College of Plant Protection/ State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
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Saeed AU, Rahman MU, Chen HF, Zheng J. Structural Insight of KSIII (β-Ketoacyl-ACP Synthase)-like Acyltransferase ChlB3 in the Biosynthesis of Chlorothricin. Molecules 2022; 27:molecules27196405. [PMID: 36234941 PMCID: PMC9573744 DOI: 10.3390/molecules27196405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 09/07/2022] [Accepted: 09/23/2022] [Indexed: 11/16/2022] Open
Abstract
Chlorothricin (CHL) belongs to a spirotetronate antibiotic family produced by Streptomyces antibioticus that inhibits pyruvate carboxylase and malate dehydrogenase. For the biosynthesis of CHL, ChlB3 plays a crucial role by introducing the 6-methylsalicylic acid (6MSA) moiety to ChlB2, an acyl carrier protein (ACP). However, the structural insight and catalytic mechanism of ChlB3 was unclear. In the current study, the crystal structure of ChlB3 was solved at 3.1 Å-resolution and a catalytic mechanism was proposed on the basis of conserved residues of structurally related enzymes. ChlB3 is a dimer having the same active sites as CerJ (a structural homologous enzyme) and uses a KSIII-like fold to work as an acyltransferase. The relaxed substrate specificity of ChlB3 was defined by its catalytic efficiencies (kcat/Km) for non-ACP tethered synthetic substrates such as 6MSA-SNAC, acetyl-SNAC, and cyclohexonyl-SNAC. ChlB3 successfully detached the 6MSA moiety from 6MSA-SNAC substrate and this hydrolytic activity demonstrated that ChlB3 has the potential to catalyze non-ACP tethered substrates. Structural comparison indicated that ChlB3 belongs to FabH family and showed 0.6–2.5 Å root mean square deviation (RMSD) with structural homologous enzymes. Molecular docking and dynamics simulations were implemented to understand substrate active site and structural behavior such as the open and closed conformation of the ChlB3 protein. The resultant catalytic and substrate recognition mechanism suggested that ChlB3 has the potential to use non-native substrates and minimize the labor of expressing ACP protein. This versatile acyltransferase activity may pave the way for manufacturing CHL variants and may help to hydrolyze several thioester-based compounds.
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Affiliation(s)
- Asad Ullah Saeed
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Mueed Ur Rahman
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, Department of Bioinformatics and Biostatistics, National Experimental Teaching Center for Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hai-Feng Chen
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, Department of Bioinformatics and Biostatistics, National Experimental Teaching Center for Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
- Shanghai Center for Bioinformation Technology, Shanghai 200235, China
| | - Jianting Zheng
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
- Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
- Correspondence:
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Chen A, Mindrebo JT, Davis TD, Kim WE, Katsuyama Y, Jiang Z, Ohnishi Y, Noel JP, Burkart MD. Mechanism-based cross-linking probes capture the Escherichia coli ketosynthase FabB in conformationally distinct catalytic states. Acta Crystallogr D Struct Biol 2022; 78:1171-1179. [PMID: 36048156 PMCID: PMC9435599 DOI: 10.1107/s2059798322007434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 07/20/2022] [Indexed: 11/10/2022] Open
Abstract
Ketosynthases (KSs) catalyse essential carbon-carbon bond-forming reactions in fatty-acid biosynthesis using a two-step, ping-pong reaction mechanism. In Escherichia coli, there are two homodimeric elongating KSs, FabB and FabF, which possess overlapping substrate selectivity. However, FabB is essential for the biosynthesis of the unsaturated fatty acids (UFAs) required for cell survival in the absence of exogenous UFAs. Additionally, FabB has reduced activity towards substrates longer than 12 C atoms, whereas FabF efficiently catalyses the elongation of saturated C14 and unsaturated C16:1 acyl-acyl carrier protein (ACP) complexes. In this study, two cross-linked crystal structures of FabB in complex with ACPs functionalized with long-chain fatty-acid cross-linking probes that approximate catalytic steps were solved. Both homodimeric structures possess asymmetric substrate-binding pockets suggestive of cooperative relationships between the two FabB monomers when engaged with C14 and C16 acyl chains. In addition, these structures capture an unusual rotamer of the active-site gating residue, Phe392, which is potentially representative of the catalytic state prior to substrate release. These structures demonstrate the utility of mechanism-based cross-linking methods to capture and elucidate conformational transitions accompanying KS-mediated catalysis at near-atomic resolution.
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Affiliation(s)
- Aochiu Chen
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Jeffrey T. Mindrebo
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
- Jack H. Skirball Center for Chemical Biology and Proteomics, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Tony D. Davis
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Woojoo E. Kim
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Yohei Katsuyama
- Department of Biotechnology, The Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Ziran Jiang
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Yasuo Ohnishi
- Department of Biotechnology, The Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Joseph P. Noel
- Jack H. Skirball Center for Chemical Biology and Proteomics, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Michael D. Burkart
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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Shinde R, Suvarna V. Fatty Acid Biosynthesis: An Updated Review on KAS Inhibitors. Curr Drug Discov Technol 2022; 19:e110122200137. [PMID: 35021976 DOI: 10.2174/1570163819666220111113032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 10/04/2021] [Accepted: 10/18/2021] [Indexed: 06/14/2023]
Abstract
Since the early twentieth century, with the isolation of penicillin and streptomycin in the 1940s, the modern era of anti-infective drug development has gained momentum. Due to the enormous success of early drug discovery, many infectious diseases were successfully prevented and eradicated. However, this initial hope was wrongheaded, and pathogens evolved as a significant threat to human health. Drug resistance develops as a result of natural selection's relentless pressure, necessitating the identification of new drug targets and the creation of chemotherapeutics that bypass existing drug resistance mechanisms. Fatty acid biosynthesis (FAS) is a crucial metabolic mechanism for bacteria during their growth and development. Several crucial enzymes involved in this biosynthetic pathway have been identified as potential targets for new antibacterial agents. In Escherichia coli (E. coli), this pathway has been extensively investigated. The present review focuses on progress in the development of Kas A, Kas B, and Fab H inhibitors as mono-therapeutic antibiotics.
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Affiliation(s)
- Rani Shinde
- Department of Quality Assurance, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai University, Mumbai, India
| | - Vasanti Suvarna
- Department of Pharmaceutical Chemistry, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai University, Mumbai, India
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Espeland LO, Georgiou C, Klein R, Bhukya H, Haug BE, Underhaug J, Mainkar PS, Brenk R. An Experimental Toolbox for Structure-Based Hit Discovery for P. aeruginosa FabF, a Promising Target for Antibiotics. ChemMedChem 2021; 16:2715-2726. [PMID: 34189850 PMCID: PMC8518799 DOI: 10.1002/cmdc.202100302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/22/2021] [Indexed: 12/12/2022]
Abstract
FabF (3-oxoacyl-[acyl-carrier-protein] synthase 2), which catalyses the rate limiting condensation reaction in the fatty acid synthesis II pathway, is an attractive target for new antibiotics. Here, we focus on FabF from P. aeruginosa (PaFabF) as antibiotics against this pathogen are urgently needed. To facilitate exploration of this target we have set up an experimental toolbox consisting of binding assays using bio-layer interferometry (BLI) as well as saturation transfer difference (STD) and WaterLOGSY NMR in addition to robust conditions for structure determination. The suitability of the toolbox to support structure-based design of FabF inhibitors was demonstrated through the validation of hits obtained from virtual screening. Screening a library of almost 5 million compounds resulted in 6 compounds for which binding into the malonyl-binding site of FabF was shown. For one of the hits, the crystal structure in complex with PaFabF was determined. Based on the obtained binding mode, analogues were designed and synthesised, but affinity could not be improved. This work has laid the foundation for structure-based exploration of PaFabF.
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Affiliation(s)
- Ludvik Olai Espeland
- Department of BiomedicineUniversity of BergenJonas Lies Vei 915020BergenNorway
- Department of ChemistryUniversity of BergenAllégaten 415007BergenNorway
| | - Charis Georgiou
- Department of BiomedicineUniversity of BergenJonas Lies Vei 915020BergenNorway
| | - Raphael Klein
- Department of BiomedicineUniversity of BergenJonas Lies Vei 915020BergenNorway
- Institute of Pharmacy and BiochemistryJohannes Gutenberg UniversityStaudingerweg 555128MainzGermany
| | - Hemalatha Bhukya
- Department of Organic Synthesis & Process ChemistryCSIR-Indian Institute of Chemical TechnologyTarnakaHyderabad500007India
| | - Bengt Erik Haug
- Department of ChemistryUniversity of BergenAllégaten 415007BergenNorway
| | - Jarl Underhaug
- Department of ChemistryUniversity of BergenAllégaten 415007BergenNorway
| | - Prathama S. Mainkar
- Department of Organic Synthesis & Process ChemistryCSIR-Indian Institute of Chemical TechnologyTarnakaHyderabad500007India
| | - Ruth Brenk
- Department of BiomedicineUniversity of BergenJonas Lies Vei 915020BergenNorway
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10
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Yang H, Mei W, Wan H, Xu R, Cheng Y. Comprehensive analysis of KCS gene family in Citrinae reveals the involvement of CsKCS2 and CsKCS11 in fruit cuticular wax synthesis at ripening. Plant Sci 2021; 310:110972. [PMID: 34315590 DOI: 10.1016/j.plantsci.2021.110972] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 05/17/2021] [Accepted: 06/08/2021] [Indexed: 05/18/2023]
Abstract
Cuticular wax covers the surface of fleshy fruit and plays a protective role in fruit development and postharvest storage, including reducing fruit water loss, resisting biotic and abiotic stress and affecting fruit glossiness. The β-ketoacyl-CoA synthase (KCS) is the rate-limiting enzyme of very long chain fatty acids (VLCFAs) synthesis, which provides precursors for the synthesis of cuticular wax. In this study, a total of 96 KCS genes were identified in six Citrinae species, including 13, 16, 21, 14, 16 and 16 KCS genes in the primitive species (Atalantia buxifolia), the wild species (Citrus ichangensis), and four cultivated species (Citrus medica, Citrus grandis, Citrus sinensis and Citrus clementina), respectively. Compared with primitive species, wild and cultivated species showed expansion of KCS gene family. Evolutionary analysis of KCS gene family indicated that uneven gain and loss of genes resulted in variable numbers of KCS genes in Citrinae, and KCS genes have undergone purifying selection. Expression profiles in C. sinensis revealed that the KCS genes had diverse expression patterns among various tissues. Furthermore, CsKCS2 and CsKCS11 were predominantly expressed in the flavedo and their expression increased sharply with ripening. Subcellular localization analysis indicated that CsKCS2 and CsKCS11 were located in the endoplasmic reticulum. Further, heterologous expression of CsKCS2 and CsKCS11 in Arabidopsis significantly increased the content of cuticular wax in leaves. Thus, CsKCS2 and CsKCS11 are involved in the accumulation of fruit cuticular wax at ripening. This work will facilitate further functional verification and understanding of the evolution of KCS genes in Citrinae.
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Affiliation(s)
- Hongbin Yang
- National R&D Center for Citrus Postharvest Technology, Wuhan, 430070, China; Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, China; College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
| | - Wanjun Mei
- National R&D Center for Citrus Postharvest Technology, Wuhan, 430070, China; Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, China; College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
| | - Haoliang Wan
- National R&D Center for Citrus Postharvest Technology, Wuhan, 430070, China; Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, China; College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
| | - Rangwei Xu
- National R&D Center for Citrus Postharvest Technology, Wuhan, 430070, China; Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, China; College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yunjiang Cheng
- National R&D Center for Citrus Postharvest Technology, Wuhan, 430070, China; Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, China; College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China.
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11
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Chai M, Queralta Castillo I, Sonntag A, Wang S, Zhao Z, Liu W, Du J, Xie H, Liao F, Yun J, Jiang Q, Sun J, Molina I, Wang ZY. A seed coat-specific β-ketoacyl-CoA synthase, KCS12, is critical for preserving seed physical dormancy. Plant Physiol 2021; 186:1606-1615. [PMID: 33779764 PMCID: PMC8260136 DOI: 10.1093/plphys/kiab152] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 03/08/2021] [Indexed: 05/21/2023]
Abstract
Physical dormancy in seeds exists widely in seed plants and plays a vital role in maintaining natural seed banks. The outermost cuticle of the seed coat forms a water-impermeable layer, which is critical for establishing seed physical dormancy. We previously set up the legume plant Medicago truncatula as an excellent model for studying seed physical dormancy, and our studies revealed that a class II KNOTTED-like homeobox, KNOX4, is a transcription factor critical for controlling hardseededness. Here we report the function of a seed coat β-ketoacyl-CoA synthase, KCS12. The expression level of KCS12 is significantly downregulated in the knox4 mutant. The KCS12 gene is predominantly expressed in the seed coat, and seed development in the M. truncatula kcs12 mutant is altered. Further investigation demonstrated that kcs12 mutant seeds lost physical dormancy and were able to absorb water without scarification treatment. Chemical analysis revealed that concentrations of C24:0 lipid polyester monomers are significantly decreased in mutant seeds, indicating that KCS12 is an enzyme that controls the production of very long chain lipid species in the seed coat. A chromatin immunoprecipitation assay demonstrated that the expression of KCS12 in the seed coat is directly regulated by the KNOX4 transcription factor. These findings define a molecular mechanism by which KNOX4 and KCS12 control formation of the seed coat and seed physical dormancy.
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Affiliation(s)
- Maofeng Chai
- Grassland Agri-Husbandry Research Center, College of Grassland Science, Qingdao Agricultural University, Qingdao 266109, China
- Noble Research Institute, Ardmore, OK 73401, USA
| | | | - Annika Sonntag
- Department of Biology, Algoma University, Sault Ste. Marie, ON, Canada, P6A 2G4
| | - Shixing Wang
- Grassland Agri-Husbandry Research Center, College of Grassland Science, Qingdao Agricultural University, Qingdao 266109, China
| | - Zhili Zhao
- Noble Research Institute, Ardmore, OK 73401, USA
| | - Wei Liu
- Noble Research Institute, Ardmore, OK 73401, USA
| | - Juan Du
- Noble Research Institute, Ardmore, OK 73401, USA
| | - Hongli Xie
- Grassland Agri-Husbandry Research Center, College of Grassland Science, Qingdao Agricultural University, Qingdao 266109, China
| | - Fuqi Liao
- Noble Research Institute, Ardmore, OK 73401, USA
| | - Jianfei Yun
- Noble Research Institute, Ardmore, OK 73401, USA
| | | | - Juan Sun
- Grassland Agri-Husbandry Research Center, College of Grassland Science, Qingdao Agricultural University, Qingdao 266109, China
| | - Isabel Molina
- Department of Biology, Algoma University, Sault Ste. Marie, ON, Canada, P6A 2G4
| | - Zeng-Yu Wang
- Grassland Agri-Husbandry Research Center, College of Grassland Science, Qingdao Agricultural University, Qingdao 266109, China
- Noble Research Institute, Ardmore, OK 73401, USA
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12
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Bartholow TG, Sztain T, Patel A, Lee DJ, Young MA, Abagyan R, Burkart MD. Elucidation of transient protein-protein interactions within carrier protein-dependent biosynthesis. Commun Biol 2021; 4:340. [PMID: 33727677 PMCID: PMC7966745 DOI: 10.1038/s42003-021-01838-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/11/2021] [Indexed: 01/31/2023] Open
Abstract
Fatty acid biosynthesis (FAB) is an essential and highly conserved metabolic pathway. In bacteria, this process is mediated by an elaborate network of protein•protein interactions (PPIs) involving a small, dynamic acyl carrier protein that interacts with dozens of other partner proteins (PPs). These PPIs have remained poorly characterized due to their dynamic and transient nature. Using a combination of solution-phase NMR spectroscopy and protein-protein docking simulations, we report a comprehensive residue-by-residue comparison of the PPIs formed during FAB in Escherichia coli. This technique describes and compares the molecular basis of six discrete binding events responsible for E. coli FAB and offers insights into a method to characterize these events and those in related carrier protein-dependent pathways.
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Affiliation(s)
- Thomas G Bartholow
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Terra Sztain
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Ashay Patel
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - D John Lee
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
- Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Megan A Young
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Ruben Abagyan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, USA
| | - Michael D Burkart
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA.
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13
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Topal T. Synthesis, Crystallographic Structure, Hirshfeld Surface Analysis, Drug-likeness Properties and Molecular Docking Studies of New Oxime-pyridine Compounds. Acta Chim Slov 2021; 68:88-101. [PMID: 34057529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023] Open
Abstract
A detailed description of the two new pyridine ligands, (2E,3Z)-3-[2-(3-chloropyridin-2-yl)hydrazinylidene]-N-hydroxybutan-2-imine and 3-chloro-2-(2Z)-2-[1-(4 nitrophenyl)ethylidene]hydrazinyl, is reported. The synthesized compounds were characterized by spectroscopic studies, spectral features were performed by TD-DFT calculations. New-generation pyridine ligand of HL2 was also determinate by single-crystal X-ray diffraction and Hirshfeld surface analysis with two-dimensional fingerprint plots was used to analyze intermolecular interactions in crystals. Molecular-docking was performed to investigate the binding areas of chemical compounds, and the results showed the inhibitory activity of the studied HL1 and HL2 against E. coli. The results of the current study revealed the drug-likeness and bioactive properties of the ligands.
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14
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Yang T, Li Y, Liu Y, He L, Liu A, Wen J, Mysore KS, Tadege M, Chen J. The 3-ketoacyl-CoA synthase WFL is involved in lateral organ development and cuticular wax synthesis in Medicago truncatula. Plant Mol Biol 2021; 105:193-204. [PMID: 33037987 DOI: 10.1007/s11103-020-01080-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 10/02/2020] [Indexed: 05/05/2023]
Abstract
A 3-ketoacyl-CoA synthase involved in biosynthesis of very long chain fatty acids and cuticular wax plays a vital role in aerial organ development in M. truncatula. Cuticular wax is composed of very long chain fatty acids and their derivatives. Defects in cuticular wax often result in organ fusion, but little is known about the role of cuticular wax in compound leaf and flower development in Medicago truncatula. In this study, through an extensive screen of a Tnt1 retrotransposon insertion population in M. truncatula, we identified four mutant lines, named wrinkled flower and leaf (wfl) for their phenotype. The phenotype of the wfl mutants is caused by a Tnt1 insertion in Medtr3g105550, encoding 3-ketoacyl-CoA synthase (KCS), which functions as a rate-limiting enzyme in very long chain fatty acid elongation. Reverse transcription-quantitative PCR showed that WFL was broadly expressed in aerial organs of the wild type, such as leaves, floral organs, and the shoot apical meristem, but was expressed at lower levels in roots. In situ hybridization showed a similar expression pattern, mainly detecting the WFL transcript in epidermal cells of the shoot apical meristem, leaf primordia, and floral organs. The wfl mutant leaves showed sparser epicuticular wax crystals on the surface and increased water permeability compared with wild type. Further analysis showed that in wfl leaves, the percentage of C20:0, C22:0, and C24:0 fatty acids was significantly increased, the amount of cuticular wax was markedly reduced, and wax constituents were altered compared to the wild type. The reduced formation of cuticular wax and wax composition changes on the leaf surface might lead to the developmental defects observed in the wfl mutants. These findings suggest that WFL plays a key role in cuticular wax formation and in the late stage of leaf and flower development in M. truncatula.
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Affiliation(s)
- Tianquan Yang
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence in Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, 650223, China
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, China
| | - Youhan Li
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence in Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, 650223, China
| | - Yu Liu
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence in Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, 650223, China
| | - Liangliang He
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence in Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, 650223, China
| | - Aizhong Liu
- Key Laboratory for Forest Resource Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, 650224, China
| | - Jiangqi Wen
- Noble Research Institute, LLC, 2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Kirankumar S Mysore
- Department of Plant and Soil Sciences, Institute for Agricultural Biosciences, Oklahoma State University, 3210 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Million Tadege
- Department of Plant and Soil Sciences, Institute for Agricultural Biosciences, Oklahoma State University, 3210 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Jianghua Chen
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence in Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, 650223, China.
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15
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Hu Y, Cronan JE. α-proteobacteria synthesize biotin precursor pimeloyl-ACP using BioZ 3-ketoacyl-ACP synthase and lysine catabolism. Nat Commun 2020; 11:5598. [PMID: 33154364 PMCID: PMC7645780 DOI: 10.1038/s41467-020-19251-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 09/28/2020] [Indexed: 11/09/2022] Open
Abstract
Pimelic acid, a seven carbon α,ω-dicarboxylic acid (heptanedioic acid), is known to provide seven of the ten biotin carbon atoms including all those of the valeryl side chain. Distinct pimelate synthesis pathways were recently elucidated in Escherichia coli and Bacillus subtilis where fatty acid synthesis plus dedicated biotin enzymes produce the pimelate moiety. In contrast, the α-proteobacteria which include important plant and mammalian pathogens plus plant symbionts, lack all of the known pimelate synthesis genes and instead encode bioZ genes. Here we report a pathway in which BioZ proteins catalyze a 3-ketoacyl-acyl carrier protein (ACP) synthase III-like reaction to produce pimeloyl-ACP with five of the seven pimelate carbon atoms being derived from glutaryl-CoA, an intermediate in lysine degradation. Agrobacterium tumefaciens strains either deleted for bioZ or which encode a BioZ active site mutant are biotin auxotrophs, as are strains defective in CaiB which catalyzes glutaryl-CoA synthesis from glutarate and succinyl-CoA.
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Affiliation(s)
- Yuanyuan Hu
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - John E Cronan
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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16
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Claver A, de la Vega M, Rey-Giménez R, Luján MÁ, Picorel R, López MV, Alfonso M. Functional analysis of β-ketoacyl-CoA synthase from biofuel feedstock Thlaspi arvense reveals differences in the triacylglycerol biosynthetic pathway among Brassicaceae. Plant Mol Biol 2020; 104:283-296. [PMID: 32740897 DOI: 10.1007/s11103-020-01042-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 07/25/2020] [Indexed: 05/22/2023]
Abstract
Differences in FAE1 enzyme affinity for the acyl-CoA substrates, as well as the balance between the different pathways involved in their incorporation to triacylglycerol might be determinant of the different composition of the seed oil in Brassicaceae. Brassicaceae present a great heterogeneity of seed oil and fatty acid composition, accumulating Very Long Chain Fatty Acids with industrial applications. However, the molecular determinants of these differences remain elusive. We have studied the β-ketoacyl-CoA synthase from the high erucic feedstock Thlaspi arvense (Pennycress). Functional characterization of the Pennycress FAE1 enzyme was performed in two Arabidopsis backgrounds; Col-0, with less than 2.5% of erucic acid in its seed oil and the fae1-1 mutant, deficient in FAE1 activity, that did not accumulate erucic acid. Seed-specific expression of the Pennycress FAE1 gene in Col-0 resulted in a 3 to fourfold increase of erucic acid content in the seed oil. This increase was concomitant with a decrease of eicosenoic acid levels without changes in oleic ones. Interestingly, only small changes in eicosenoic and erucic acid levels occurred when the Pennycress FAE1 gene was expressed in the fae1-1 mutant, with high levels of oleic acid available for elongation, suggesting that the Pennycress FAE1 enzyme showed higher affinity for eicosenoic acid substrates, than for oleic ones in Arabidopsis. Erucic acid was incorporated to triacylglycerol in the transgenic lines without significant changes in their levels in the diacylglycerol fraction, suggesting that erucic acid was preferentially incorporated to triacylglycerol via DGAT1. Expression analysis of FAE1, AtDGAT1, AtLPCAT1 and AtPDAT1 genes in the transgenic lines further supported this conclusion. Differences in FAE1 affinity for the oleic and eicosenoic substrates among Brassicaceae, as well as their incorporation to triacylglycerol might explain the differences in composition of their seed oil.
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Affiliation(s)
- Ana Claver
- Department of Plant Nutrition, Estación Experimental de Aula Dei-CSIC, Avda. Montañana 1005, 50059, Zaragoza, Spain
| | - Marina de la Vega
- Department of Plant Nutrition, Estación Experimental de Aula Dei-CSIC, Avda. Montañana 1005, 50059, Zaragoza, Spain
| | - Raquel Rey-Giménez
- Laboratorio Agroambiental, Gobierno de Aragón, Avda. Montañana 1005, 50071, Zaragoza, Spain
| | - María Á Luján
- Department of Plant Nutrition, Estación Experimental de Aula Dei-CSIC, Avda. Montañana 1005, 50059, Zaragoza, Spain
| | - Rafael Picorel
- Department of Plant Nutrition, Estación Experimental de Aula Dei-CSIC, Avda. Montañana 1005, 50059, Zaragoza, Spain
| | - M Victoria López
- Department of Soil and Water, Estación Experimental de Aula Dei-CSIC, Avda. Montañana 1005, 50059, Zaragoza, Spain
| | - Miguel Alfonso
- Department of Plant Nutrition, Estación Experimental de Aula Dei-CSIC, Avda. Montañana 1005, 50059, Zaragoza, Spain.
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17
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Van Dolah FM, Morey JS, Milne S, Ung A, Anderson PE, Chinain M. Transcriptomic analysis of polyketide synthases in a highly ciguatoxic dinoflagellate, Gambierdiscus polynesiensis and low toxicity Gambierdiscus pacificus, from French Polynesia. PLoS One 2020; 15:e0231400. [PMID: 32294110 PMCID: PMC7159223 DOI: 10.1371/journal.pone.0231400] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 03/23/2020] [Indexed: 11/18/2022] Open
Abstract
Marine dinoflagellates produce a diversity of polyketide toxins that are accumulated in marine food webs and are responsible for a variety of seafood poisonings. Reef-associated dinoflagellates of the genus Gambierdiscus produce toxins responsible for ciguatera poisoning (CP), which causes over 50,000 cases of illness annually worldwide. The biosynthetic machinery for dinoflagellate polyketides remains poorly understood. Recent transcriptomic and genomic sequencing projects have revealed the presence of Type I modular polyketide synthases in dinoflagellates, as well as a plethora of single domain transcripts with Type I sequence homology. The current transcriptome analysis compares polyketide synthase (PKS) gene transcripts expressed in two species of Gambierdiscus from French Polynesia: a highly toxic ciguatoxin producer, G. polynesiensis, versus a non-ciguatoxic species G. pacificus, each assembled from approximately 180 million Illumina 125 nt reads using Trinity, and compares their PKS content with previously published data from other Gambierdiscus species and more distantly related dinoflagellates. Both modular and single-domain PKS transcripts were present. Single domain β-ketoacyl synthase (KS) transcripts were highly amplified in both species (98 in G. polynesiensis, 99 in G. pacificus), with smaller numbers of standalone acyl transferase (AT), ketoacyl reductase (KR), dehydratase (DH), enoyl reductase (ER), and thioesterase (TE) domains. G. polynesiensis expressed both a larger number of multidomain PKSs, and larger numbers of modules per transcript, than the non-ciguatoxic G. pacificus. The largest PKS transcript in G. polynesiensis encoded a 10,516 aa, 7 module protein, predicted to synthesize part of the polyether backbone. Transcripts and gene models representing portions of this PKS are present in other species, suggesting that its function may be performed in those species by multiple interacting proteins. This study contributes to the building consensus that dinoflagellates utilize a combination of Type I modular and single domain PKS proteins, in an as yet undefined manner, to synthesize polyketides.
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Affiliation(s)
- Frances M. Van Dolah
- Marine Genomics Core, Hollings Marine Laboratory, Charleston, SC, United States of America
- * E-mail:
| | - Jeanine S. Morey
- Marine Genomics Core, Hollings Marine Laboratory, Charleston, SC, United States of America
| | - Shard Milne
- Charleston Computational Genomics Group, Department of Computer Science, College of Charleston, Charleston, SC, United States of America
| | - André Ung
- Laboratoire des Biotoxines Marines, Institut Louis Malardé—UMR 241 EIO, Papeete, Tahiti, French Polynesia
| | - Paul E. Anderson
- Charleston Computational Genomics Group, Department of Computer Science, College of Charleston, Charleston, SC, United States of America
| | - Mireille Chinain
- Laboratoire des Biotoxines Marines, Institut Louis Malardé—UMR 241 EIO, Papeete, Tahiti, French Polynesia
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18
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Norlina R, Norashikin MN, Loh SH, Aziz A, Cha TS. Exogenous Abscisic Acid Supplementation at Early Stationary Growth Phase Triggers Changes in the Regulation of Fatty Acid Biosynthesis in Chlorella vulgaris UMT-M1. Appl Biochem Biotechnol 2020; 191:1653-1669. [PMID: 32198601 DOI: 10.1007/s12010-020-03312-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 03/12/2020] [Indexed: 11/30/2022]
Abstract
Abscisic acid (ABA) has been known to exist in a microalgal system and serves as one of the chemical stimuli in various biological pathways. Nonetheless, the involvement of ABA in fatty acid biosynthesis, particularly at the transcription level in microalgae is poorly understood. The objective of this study was to determine the effects of exogenous ABA on growth, total oil content, fatty acid composition, and the expression level of beta ketoacyl-ACP synthase I (KAS I) and omega-3 fatty acid desaturase (ω-3 FAD) genes in Chlorella vulgaris UMT-M1. ABA was applied to early stationary C. vulgaris cultures at concentrations of 0, 10, 20, and 80 μM for 48 h. The results showed that ABA significantly increased biomass production and total oil content. The increment of palmitic (C16:0) and stearic (C18:0) acids was coupled by decrement in linoleic (C18:2) and α-linolenic (C18:3n3) acids. Both KAS I and ω-3 FAD gene expression were downregulated, which was negatively correlated to saturated fatty acid (SFAs), but positively correlated to polyunsaturated fatty acid (PUFA) accumulations. Further analysis of both KAS I and ω-3 FAD promoters revealed the presence of multiple ABA-responsive elements (ABREs) in addition to other phytohormone-responsive elements. However, the role of these phytohormone-responsive elements in regulating KAS I and ω-3 FAD gene expression still remains elusive. This revelation might suggest that phytohormone-responsive gene regulation in C. vulgaris and microalgae as a whole might diverge from higher plants which deserve further scientific research to elucidate its functional roles.
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Affiliation(s)
- Ramlee Norlina
- Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030, Kuala Terengganu, Terengganu, Malaysia
| | - Md Nor Norashikin
- Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030, Kuala Terengganu, Terengganu, Malaysia
| | - Saw Hong Loh
- Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030, Kuala Terengganu, Terengganu, Malaysia
| | - Ahmad Aziz
- Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030, Kuala Terengganu, Terengganu, Malaysia
| | - Thye San Cha
- Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030, Kuala Terengganu, Terengganu, Malaysia.
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19
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Cummings M, Peters AD, Whitehead GFS, Menon BRK, Micklefield J, Webb SJ, Takano E. Assembling a plug-and-play production line for combinatorial biosynthesis of aromatic polyketides in Escherichia coli. PLoS Biol 2019; 17:e3000347. [PMID: 31318855 PMCID: PMC6638757 DOI: 10.1371/journal.pbio.3000347] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 06/14/2019] [Indexed: 11/19/2022] Open
Abstract
Polyketides are a class of specialised metabolites synthesised by both eukaryotes and prokaryotes. These chemically and structurally diverse molecules are heavily used in the clinic and include frontline antimicrobial and anticancer drugs such as erythromycin and doxorubicin. To replenish the clinicians' diminishing arsenal of bioactive molecules, a promising strategy aims at transferring polyketide biosynthetic pathways from their native producers into the biotechnologically desirable host Escherichia coli. This approach has been successful for type I modular polyketide synthases (PKSs); however, despite more than 3 decades of research, the large and important group of type II PKSs has until now been elusive in E. coli. Here, we report on a versatile polyketide biosynthesis pipeline, based on identification of E. coli-compatible type II PKSs. We successfully express 5 ketosynthase (KS) and chain length factor (CLF) pairs-e.g., from Photorhabdus luminescens TT01, Streptomyces resistomycificus, Streptoccocus sp. GMD2S, Pseudoalteromonas luteoviolacea, and Ktedonobacter racemifer-as soluble heterodimeric recombinant proteins in E. coli for the first time. We define the anthraquinone minimal PKS components and utilise this biosynthetic system to synthesise anthraquinones, dianthrones, and benzoisochromanequinones (BIQs). Furthermore, we demonstrate the tolerance and promiscuity of the anthraquinone heterologous biosynthetic pathway in E. coli to act as genetically applicable plug-and-play scaffold, showing it to function successfully when combined with enzymes from phylogenetically distant species, endophytic fungi and plants, which resulted in 2 new-to-nature compounds, neomedicamycin and neochaetomycin. This work enables plug-and-play combinatorial biosynthesis of aromatic polyketides using bacterial type II PKSs in E. coli, providing full access to its many advantages in terms of easy and fast genetic manipulation, accessibility for high-throughput robotics, and convenient biotechnological scale-up. Using the synthetic and systems biology toolbox, this plug-and-play biosynthetic platform can serve as an engine for the production of new and diversified bioactive polyketides in an automated, rapid, and versatile fashion.
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Affiliation(s)
- Matthew Cummings
- Manchester Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, United Kingdom
| | - Anna D. Peters
- Manchester Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, United Kingdom
| | - George F. S. Whitehead
- Manchester Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, United Kingdom
| | - Binuraj R. K. Menon
- Manchester Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, United Kingdom
- Warwick Integrative Synthetic Biology Centre, WISB, School of Life Sciences, The University of Warwick, Coventry, United Kingdom
| | - Jason Micklefield
- Manchester Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, United Kingdom
| | - Simon J. Webb
- Manchester Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, United Kingdom
| | - Eriko Takano
- Manchester Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Manchester, United Kingdom
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Horinouchi M, Malon M, Hirota H, Hayashi T. Identification of 4-methyl-5-oxo-octane-1,8-dioic acid and the derivatives as metabolites of steroidal C,D-ring degradation in Comamonas testosteroni TA441. J Steroid Biochem Mol Biol 2019; 185:277-286. [PMID: 30026063 DOI: 10.1016/j.jsbmb.2018.07.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/10/2018] [Accepted: 07/10/2018] [Indexed: 10/28/2022]
Abstract
Comamonas testosteroni TA441 degrades steroids via 9,17-dioxo-1,2,3,4,10,19-hexanorandrostan-5-oic acid, which is presumed to be further degraded by β-oxidation. In the β-oxidation process, Coenzyme A (CoA)-ester of 9-oxo-1,2,3,4,5,6,10,19-octanor-13,17-secoandrost-8(14)-ene-7,17-dioic acid is produced and converted by β-ketoacyl-CoA-transferase encoded by ORF1 and ORF2 (scdL1L2) to cleave the remaining C-ring. In this study, we isolated and identified 4-methyl-5-oxo-octane-1,8-dioic acid and 4-methyl-5-oxo-3-octene-1,8-dioic acid from the culture of the ORF3 (scdN)-null mutant as metabolites of steroid degradation (ADD and cholic acid analogues; cholic acid, chenodeoxycholic acid, deoxycholic acid, and lithocholic acid). In addition of these compounds, UHPLC/MS analysis of the culture of the scdN-null mutant revealed significant accumulation of another compound, which was detected as a dominant peak of m/z 155 ([M-CO2]-) accompanied by a small peak of parental ion (m/z 199 [M-]). On the bases of experimental data, this compound was presumed to be 4-methyl-5-oxo-2-octene-1,8-dioic acid, whose CoA-ester was indicated to be converted by scdN-encoded CoA-hydratase into the CoA-ester of 3-hydroxy-4-methyl-5-oxooctan-1,7-carboxylic acid.
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Affiliation(s)
- Masae Horinouchi
- Environmental Molecular Biology Laboratory, RIKEN, Saitama, 351-0198 Japan.
| | - Michal Malon
- Molecular Characterization Team, RIKEN, Saitama, 351-0198 Japan
| | | | - Toshiaki Hayashi
- Environmental Molecular Biology Laboratory, RIKEN, Saitama, 351-0198 Japan
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Hou J, Zheng H, Tzou WS, Cooper DR, Chruszcz M, Chordia MD, Kwon K, Grabowski M, Minor W. Differences in substrate specificity of V. cholerae FabH enzymes suggest new approaches for the development of novel antibiotics and biofuels. FEBS J 2018; 285:2900-2921. [PMID: 29917313 PMCID: PMC6105497 DOI: 10.1111/febs.14588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 05/31/2018] [Accepted: 06/15/2018] [Indexed: 01/14/2023]
Abstract
Vibrio cholerae, the causative pathogen of the life-threatening infection cholera, encodes two copies of β-ketoacyl-acyl carrier protein synthase III (vcFabH1 and vcFabH2). vcFabH1 and vcFabH2 are pathogenic proteins associated with fatty acid synthesis, lipid metabolism, and potential applications in biofuel production. Our biochemical assays characterize vcFabH1 as exhibiting specificity for acetyl-CoA and CoA thioesters with short acyl chains, similar to that observed for FabH homologs found in most gram-negative bacteria. vcFabH2 prefers medium chain-length acyl-CoA thioesters, particularly octanoyl-CoA, which is a pattern of specificity rarely seen in bacteria. Structural characterization of one vcFabH1 and six vcFabH2 structures determined in either apo form or in complex with acetyl-CoA/octanoyl-CoA indicate that the substrate-binding pockets of vcFabH1 and vcFabH2 are of different sizes, accounting for variations in substrate chain-length specificity. An unusual and unique feature of vcFabH2 is its C-terminal fragment that interacts with both the substrate-entrance loop and the dimer interface of the enzyme. Our discovery of the pattern of substrate specificity of both vcFabH1 and vcFabH2 can potentially aid the development of novel antibacterial agents against V. cholerae. Additionally, the distinctive substrate preference of FabH2 in V. cholerae and related facultative anaerobes conceivably make it an attractive component of genetically engineered bacteria used for commercial biofuel production.
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Affiliation(s)
- Jing Hou
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA
- Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA
| | - Heping Zheng
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA
- Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA
| | - Wen-Shyong Tzou
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Taiwan
| | - David R. Cooper
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA
- Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA
| | - Maksymilian Chruszcz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA
| | - Mahendra D. Chordia
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA
- Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA
| | - Keehwan Kwon
- Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA
- Infectious Diseases, J. Craig Venter Institute, Rockville, MD 20850, USA
| | - Marek Grabowski
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA
- Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA
| | - Wladek Minor
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908-0736, USA
- Center for Structural Genomics of Infectious Diseases (CSGID) Consortium, USA
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Li C, Haslam TM, Krüger A, Schneider LM, Mishina K, Samuels L, Yang H, Kunst L, Schaffrath U, Nawrath C, Chen G, Komatsuda T, von Wettstein-Knowles P. The β-Ketoacyl-CoA Synthase HvKCS1, Encoded by Cer-zh, Plays a Key Role in Synthesis of Barley Leaf Wax and Germination of Barley Powdery Mildew. Plant Cell Physiol 2018; 59:806-822. [PMID: 29401261 DOI: 10.1093/pcp/pcy020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 01/24/2018] [Indexed: 05/05/2023]
Abstract
The cuticle coats the primary aerial surfaces of land plants. It consists of cutin and waxes, which provide protection against desiccation, pathogens and herbivores. Acyl cuticular waxes are synthesized via elongase complexes that extend fatty acyl precursors up to 38 carbons for downstream modification pathways. The leaves of 21 barley eceriferum (cer) mutants appear to have less or no epicuticular wax crystals, making these mutants excellent tools for identifying elongase and modification pathway biosynthetic genes. Positional cloning of the gene mutated in cer-zh identified an elongase component, β-ketoacyl-CoA synthase (CER-ZH/HvKCS1) that is one of 34 homologous KCSs encoded by the barley genome. The biochemical function of CER-ZH was deduced from wax and cutin analyses and by heterologous expression in yeast. Combined, these experiments revealed that CER-ZH/HvKCS1 has a substrate specificity for C16-C20, especially unsaturated, acyl chains, thus playing a major role in total acyl chain elongation for wax biosynthesis. The contribution of CER-ZH to water barrier properties of the cuticle and its influence on the germination of barley powdery mildew fungus were also assessed.
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Affiliation(s)
- Chao Li
- Laboratory of Plant Stress Ecophysiology and Biotechnology, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
- National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, 305-8602 Japan
- Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai 201602, China
| | - Tegan M Haslam
- Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Anna Krüger
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany
| | - Lizette M Schneider
- Section for Biomolecular Sciences, Department of Biology, University of Copenhagen, DK-2200 Copenhagen N, Denmark
- Department of Biology, University of Lund, SW-22362 Lund, Sweden
| | - Kohei Mishina
- National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, 305-8602 Japan
| | - Lacey Samuels
- Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Hongxing Yang
- Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai 201602, China
| | - Ljerka Kunst
- Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Ulrich Schaffrath
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany
| | - Christiane Nawrath
- Department of Plant Molecular Biology, University of Lausanne, CH-1015 Lausanne, Switzerland
| | - Guoxiong Chen
- Laboratory of Plant Stress Ecophysiology and Biotechnology, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Takao Komatsuda
- National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, 305-8602 Japan
| | - Penny von Wettstein-Knowles
- Section for Biomolecular Sciences, Department of Biology, University of Copenhagen, DK-2200 Copenhagen N, Denmark
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Gan L, Zhu S, Zhao Z, Liu L, Wang X, Zhang Z, Zhang X, Wang J, Wang J, Guo X, Wan J. Wax Crystal-Sparse Leaf 4, encoding a β-ketoacyl-coenzyme A synthase 6, is involved in rice cuticular wax accumulation. Plant Cell Rep 2017; 36:1655-1666. [PMID: 28733852 DOI: 10.1007/s00299-017-2181-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Accepted: 07/09/2017] [Indexed: 06/07/2023]
Abstract
WSL4 encodes a KCS6 protein which is required for cuticular wax accumulation in rice. Very long chain fatty acids (VLCFAs) are essential precursors for cuticular wax biosynthesis. VLCFA biosynthesis occurs in the endoplasmic reticulum and requires the fatty acid elongase (FAE) complex. The β-ketoacyl-coenzyme A synthase (KCS) catalyzes the first step of FAE-mediated VLCFA elongation. Here we characterized the Wax Crystal-Sparse Leaf 4 (WSL4) gene involved in leaf cuticular wax accumulation in rice. The wsl4 mutant displayed a pleiotropic phenotype including dwarfism, less tiller numbers and reduced surface wax load. Map-based cloning and nucleotide sequencing results revealed that wsl4 carried a single nucleotide substitution in the second exon of a putative KCS6 gene, encoding one subunit of the FAE complex for VLCFAs. Genetic complementation confirmed that the mutation in WSL4 was responsible for the phenotype of wsl4. WSL4 was constitutively expressed in various rice tissues and localized in the endoplasmic reticulum. Both WSL4-RNAi transgenic lines and WSL4 knocked-out mutants exhibited wax-deficient phenotypes similar to the wsl4 mutant. These data indicate that WSL4 is required for cuticular wax accumulation in rice.
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Affiliation(s)
- Lu Gan
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Shanshan Zhu
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhichao Zhao
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Linglong Liu
- National Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiaole Wang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhe Zhang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xin Zhang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Jie Wang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Jiulin Wang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xiuping Guo
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Jianmin Wan
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
- National Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China.
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Ke X, Zou W, Ren Y, Wang Z, Li J, Wu X, Zhao J. Functional divergence of chloroplast Cpn60α subunits during Arabidopsis embryo development. PLoS Genet 2017; 13:e1007036. [PMID: 28961247 PMCID: PMC5636168 DOI: 10.1371/journal.pgen.1007036] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 10/11/2017] [Accepted: 09/20/2017] [Indexed: 02/03/2023] Open
Abstract
Chaperonins are a class of molecular chaperones that assist in the folding and assembly of a wide range of substrates. In plants, chloroplast chaperonins are composed of two different types of subunits, Cpn60α and Cpn60β, and duplication of Cpn60α and Cpn60β genes occurs in a high proportion of plants. However, the importance of multiple Cpn60α and Cpn60β genes in plants is poorly understood. In this study, we found that loss-of-function of CPNA2 (AtCpn60α2), a gene encoding the minor Cpn60α subunit in Arabidopsis thaliana, resulted in arrested embryo development at the globular stage, whereas the other AtCpn60α gene encoding the dominant Cpn60α subunit, CPNA1 (AtCpn60α1), mainly affected embryonic cotyledon development at the torpedo stage and thereafter. Further studies demonstrated that CPNA2 can form a functional chaperonin with CPNB2 (AtCpn60β2) and CPNB3 (AtCpn60β3), while the functional partners of CPNA1 are CPNB1 (AtCpn60β1) and CPNB2. We also revealed that the functional chaperonin containing CPNA2 could assist the folding of a specific substrate, KASI (β-ketoacyl-[acyl carrier protein] synthase I), and that the KASI protein level was remarkably reduced due to loss-of-function of CPNA2. Furthermore, the reduction in the KASI protein level was shown to be the possible cause for the arrest of cpna2 embryos. Our findings indicate that the two Cpn60α subunits in Arabidopsis play different roles during embryo development through forming distinct chaperonins with specific AtCpn60β to assist the folding of particular substrates, thus providing novel insights into functional divergence of Cpn60α subunits in plants. Chaperonins are large oligomeric complexes that are involved in the folding and assembly of numerous proteins in various species. In contrast to other types of chaperonins, chloroplast chaperonins are characterized by the hetero-oligomeric structure composed of two unique types of subunits, Cpn60α and Cpn60β, each of which is present in two or more paralogous forms in most of higher plants. However, the functional significance underlying the wide array of subunit types and complex oligomeric arrangement remains largely unknown. Here, we investigated the role of the minor Cpn60α subunit AtCpn60α2 in Arabidopsis embryo development, and found that AtCpn60α2 is important for the transition of globular embryos to heart-shaped embryos, whereas loss of the dominant Cpn60α subunit AtCpn60α1 affects embryonic cotyledon development. Further studies demonstrated that AtCpn60α2 could form functional chaperonins with AtCpn60β2 and AtCpn60β3 to specifically assist in folding of the substrate KASI, which is important for the formation of heart-shaped embryos. Our results suggest that duplication of Cpn60α genes in higher plants can increase the potential number of chloroplast chaperonin substrates and provide chloroplast chaperonins with more roles in plant growth and development, thus revealing the relationship between duplication and functional specialization of chaperonin genes.
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Affiliation(s)
- Xiaolong Ke
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Wenxuan Zou
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yafang Ren
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Zhiqin Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jin Li
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xuan Wu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jie Zhao
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
- * E-mail:
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Xiong W, Wei Q, Wu P, Zhang S, Li J, Chen Y, Li M, Jiang H, Wu G. Molecular cloning and characterization of two β-ketoacyl-acyl carrier protein synthase I genes from Jatropha curcas L. J Plant Physiol 2017; 214:152-160. [PMID: 28521208 DOI: 10.1016/j.jplph.2017.05.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 04/28/2017] [Accepted: 05/02/2017] [Indexed: 06/07/2023]
Abstract
The β-ketoacyl-acyl carrier protein synthase I (KASI) is involved in de novo fatty acid biosynthesis in many organisms. Two putative KASI genes, JcKASI-1 and JcKASI-2, were isolated from Jatropha curcas. The deduced amino acid sequences of JcKASI-1 and JcKASI-2 exhibit around 83.8% and 72.5% sequence identities with AtKASI, respectively, and both contain conserved Cys-His-Lys-His-Phe catalytic active sites. Phylogenetic analysis indicated that JcKASI-2 belongs to a clade with several KASI proteins from dicotyledonous plants. Both JcKASI genes were expressed in multiple tissues, most strongly in filling stage seeds of J. curcas. Additionally, the JcKASI-1 and JcKASI-2 proteins were both localized to the plastids. Expressing JcKASI-1 in the Arabidopsis kasI mutant rescued the mutant's phenotype and restored the fatty acid composition and oil content in seeds to wild-type, but expressing JcKASI-2 in the Arabidopsis kasI mutant resulted in only partial rescue. This implies that JcKASI-1 and JcKASI-2 exhibit partial functional redundancy and KASI genes play a universal role in regulating fatty acid biosynthesis, growth, and development in plants.
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Affiliation(s)
- Wangdan Xiong
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Qian Wei
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Pingzhi Wu
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, PR China
| | - Sheng Zhang
- Guangzhou Institution of Biomedicine and Health, Chinese Academy of Chinese, Guangzhou 510530, PR China
| | - Jun Li
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yaping Chen
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, PR China
| | - Meiru Li
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, PR China
| | - Huawu Jiang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, PR China
| | - Guojiang Wu
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, PR China.
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26
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Wang X, Guan Y, Zhang D, Dong X, Tian L, Qu LQ. A β-Ketoacyl-CoA Synthase Is Involved in Rice Leaf Cuticular Wax Synthesis and Requires a CER2-LIKE Protein as a Cofactor. Plant Physiol 2017; 173:944-955. [PMID: 27913740 PMCID: PMC5291035 DOI: 10.1104/pp.16.01527] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 11/30/2016] [Indexed: 05/18/2023]
Abstract
Cuticular waxes are complex mixtures of very-long-chain fatty acids (VLCFAs) and their derivatives, forming a natural barrier on aerial surfaces of terrestrial plants against biotic and abiotic stresses. In VLCFA biosynthesis, β-ketoacyl-CoA synthase (KCS) is the key enzyme, catalyzing the first reaction in fatty acid elongation and determining substrate specificity. We isolated a rice (Oryza sativa) wax crystal-sparse leaf 4 (WSL4) gene using a map-based cloning strategy. WSL4 is predicted to encode a KCS, a homolog of Arabidopsis (Arabidopsis thaliana) CER6. Complementation of the mutant wsl4-1 with WSL4 genomic DNA rescued the cuticular wax-deficient phenotype, confirming the function of WSL4 The load of wax components longer than 30 carbons (C30) and C28 were reduced markedly in wsl4-1 and wsl4-2 mutants, respectively. Overexpression of WSL4 increased the cuticular wax load in rice leaves. We further isolated a cofactor of WSL4, OsCER2, a homolog of Arabidopsis CER2, by coimmunoprecipitation and confirmed their physical interaction by split-ubiquitin yeast two-hybrid experiments. Expression of WSL4 alone in elo3 yeast cells resulted in increased C24 but did not produce VLCFAs of greater length, whereas expressing OsCER2 alone showed no effect. Coexpression of WSL4 and OsCER2 in elo3 yeast cells yielded fatty acids up to C30. OsCER2 with a mutated HxxxD motif (H172E, D176A, and D176H) interrupted its interaction with WSL4 and failed to elongate VLCFAs past C24 when expressed with WSL4 in elo3 yeast cells. These results demonstrated that WSL4 was involved in VLCFA elongation beyond C22 and that elongation beyond C24 required the participation of OsCER2.
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Affiliation(s)
- Xiaochen Wang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Yuanyuan Guan
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Du Zhang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Xiangbai Dong
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Lihong Tian
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Le Qing Qu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
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Jeon D, Jeong MC, Jnawali HN, Kwak C, Ryoo S, Jung ID, Kim Y. Phloretin Exerts Anti-Tuberculosis Activity and Suppresses Lung Inflammation. Molecules 2017; 22:molecules22010183. [PMID: 28117761 PMCID: PMC6155841 DOI: 10.3390/molecules22010183] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 01/17/2017] [Accepted: 01/18/2017] [Indexed: 12/12/2022] Open
Abstract
An increase in the prevalence of the drug-resistant Mycobacteria tuberculosis necessitates developing new types of anti-tuberculosis drugs. Here, we found that phloretin, a naturally-occurring flavonoid, has anti-mycobacterial effects on H37Rv, multi-drug-, and extensively drug-resistant clinical isolates, with minimum inhibitory concentrations of 182 and 364 μM, respectively. Since Mycobacteria cause lung inflammation that contributes to tuberculosis pathogenesis, anti-inflammatory effects of phloretin in interferon-γ-stimulated MRC-5 human lung fibroblasts and lipopolysaccharide (LPS)-stimulated dendritic cells were investigated. The release of interleukin (IL)-1β, IL-12, and tumor necrosis factor (TNF)-α was inhibited by phloretin. The mRNA levels of IL-1β, IL-6, IL-12, TNF-α, and matrix metalloproteinase-1, as well as p38 mitogen-activated protein kinase and extracellular signal-regulated kinase phosphorylation, were suppressed. A mouse in vivo study of LPS-stimulated lung inflammation showed that phloretin effectively suppressed the levels of TNF-α, IL-1β, and IL-6 in lung tissue with low cytotoxicity. Phloretin was found to bind M. tuberculosis β-ketoacyl acyl carrier protein synthase III (mtKASIII) with high affinity (7.221 × 107 M−1); a binding model showed hydrogen bonding of A-ring 2′-hydroxy and B-ring 4-hydroxy groups of phloretin with Asn261 and Cys122 of mtKASIII, implying that mtKASIII can be a potential target protein. Therefore, phloretin can be a useful dietary natural product with anti-tuberculosis benefits.
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Affiliation(s)
- Dasom Jeon
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea.
| | - Min-Cheol Jeong
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea.
| | - Hum Nath Jnawali
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea.
| | - Chulhee Kwak
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea.
| | - Sungwon Ryoo
- Korean National Tuberculosis Association, Seoul 06763, Korea.
| | - In Duk Jung
- Department of Immunology, School of Medicine, Konkuk University, Seoul 05029, Korea.
| | - Yangmee Kim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea.
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Yu F, Yu X, Yu H, Hu M, Qu J, Zhu K, Wang M. [Effect of cis-vaccinate acid on swarming ability of Pseudomonas aeruginosa]. Wei Sheng Wu Xue Bao 2015; 55:1600-1607. [PMID: 27101703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To study the effect of fatty acids composition on swarming mobility in Pseudomonas aeruginosa. METHODS We constructed a fabF-knockout mutant of PAO1 (YFF-1) by double exchange principle, overexpressed FabF in YFF-1 mutant to recover the mobility, and compared the swarming ability of wild type, YFF-1 mutant and mutant with plasmid pUCP18Gm-fabF. The change of fatty acids composition was analyzed using gas chromatography to explain the difference of swarming ability. RESULTS Swarming ability disappeared in YFF-1 mutant and was recovered in YFF-1 with plasmid pUCP18Gm-fabF. Gas chromatography analysis revealed that fatty acids composition changed in YFF-1. The cis-vaccinate acid (C18:1delta11) content decreased from 33.6% to 8.9%, and the ratio of unsaturated fatty acids to saturated fatty acids (UFA: SFA) was deduced from 0.96 to 0.74. The recovery of cis-vaccinate acid content was 20.9% and UFA:SFA 1.09 after expression of fabF. CONCLUSION Expression level of FabF played an important role in regulating swarming ability of PAO1. The decrease of cis-vaccinate acid content and unsaturation degree of fatty acids, especially the sharp decrease of cis-vaccinate acid, may be vital causes of swarming ability disappearance in YFF-1.
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Mao YH, Ma JC, Li F, Hu Z, Wang HH. Ralstonia solanacearum RSp0194 Encodes a Novel 3-Keto-Acyl Carrier Protein Synthase III. PLoS One 2015; 10:e0136261. [PMID: 26305336 PMCID: PMC4549310 DOI: 10.1371/journal.pone.0136261] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 08/03/2015] [Indexed: 11/18/2022] Open
Abstract
Fatty acid synthesis (FAS), a primary metabolic pathway, is essential for survival of bacteria. Ralstonia solanacearum, a β-proteobacteria member, causes a bacterial wilt affecting more than 200 plant species, including many economically important plants. However, thus far, the fatty acid biosynthesis pathway of R. solanacearum has not been well studied. In this study, we characterized two forms of 3-keto-ACP synthase III, RsFabH and RsFabW, in R. solanacearum. RsFabH, the homologue of Escherichia coli FabH, encoded by the chromosomal RSc1050 gene, catalyzes the condensation of acetyl-CoA with malonyl-ACP in the initiation steps of fatty acid biosynthesis in vitro. The RsfabH mutant lost de novo fatty acid synthetic ability, and grows in medium containing free fatty acids. RsFabW, a homologue of Pseudomonas aeruginosa PA3286, encoded by a megaplasmid gene, RSp0194, condenses acyl-CoA (C2-CoA to C10-CoA) with malonyl-ACP to produce 3-keto-acyl-ACP in vitro. Although the RsfabW mutant was viable, RsfabW was responsible for RsfabH mutant growth on medium containing free fatty acids. Our results also showed that RsFabW could condense acyl-ACP (C4-ACP to C8-ACP) with malonyl-ACP, to produce 3-keto-acyl-ACP in vitro, which implies that RsFabW plays a special role in fatty acid synthesis of R. solanacearum. All of these data confirm that R. solanacearum not only utilizes acetyl-CoA, but also, utilizes medium-chain acyl-CoAs or acyl-ACPs as primers to initiate fatty acid synthesis.
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Affiliation(s)
- Ya-Hui Mao
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Jin-Cheng Ma
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Feng Li
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Zhe Hu
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Hai-Hong Wang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong 510642, China
- * E-mail:
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Jusoh M, Loh SH, Chuah TS, Aziz A, Cha TS. Indole-3-acetic acid (IAA) induced changes in oil content, fatty acid profiles and expression of four fatty acid biosynthetic genes in Chlorella vulgaris at early stationary growth phase. Phytochemistry 2015; 111:65-71. [PMID: 25583439 DOI: 10.1016/j.phytochem.2014.12.022] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 12/01/2014] [Accepted: 12/16/2014] [Indexed: 05/03/2023]
Abstract
Microalgae lipids and oils are potential candidates for renewable biodiesel. Many microalgae species accumulate a substantial amount of lipids and oils under environmental stresses. However, low growth rate under these adverse conditions account for the decrease in overall biomass productivity which directly influence the oil yield. This study was undertaken to investigate the effect of exogenously added auxin (indole-3-acetic acid; IAA) on the oil content, fatty acid compositions, and the expression of fatty acid biosynthetic genes in Chlorella vulgaris (UMT-M1). Auxin has been shown to regulate growth and metabolite production of several microalgae. Results showed that oil accumulation was highest on days after treatment (DAT)-2 with enriched levels of palmitic (C16:0) and stearic (C18:0) acids, while the linoleic (C18:2) and α-linolenic (C18:3n3) acids levels were markedly reduced by IAA. The elevated levels of saturated fatty acids (C16:0 and C18:0) were consistent with high expression of the β-ketoacyl ACP synthase I (KAS I) gene, while low expression of omega-6 fatty acid desaturase (ω-6 FAD) gene was consistent with low production of C18:2. However, the increment of stearoyl-ACP desaturase (SAD) gene expression upon IAA induction did not coincide with oleic acid (C18:1) production. The expression of omega-3 fatty acid desaturase (ω-3 FAD) gene showed a positive correlation with the synthesis of PUFA and C18:3n3.
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Affiliation(s)
- Malinna Jusoh
- School of Fundamental Sciences, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia.
| | - Saw Hong Loh
- School of Marine Science and Environment, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia.
| | - Tse Seng Chuah
- School of Food Science and Technology, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia.
| | - Ahmad Aziz
- School of Food Science and Technology, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia.
| | - Thye San Cha
- School of Fundamental Sciences, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia; Institute of Marine Biotechnology, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia.
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Weidenbach D, Jansen M, Bodewein T, Nagel KA, Schaffrath U. Shoot and root phenotyping of the barley mutant kcs6 (3-ketoacyl-CoA synthase6) depleted in epicuticular waxes under water limitation. Plant Signal Behav 2015; 10:1-3. [PMID: 25876181 PMCID: PMC4622470 DOI: 10.1080/15592324.2014.1003752] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 12/19/2014] [Accepted: 12/22/2014] [Indexed: 05/18/2023]
Abstract
Aerial parts of plants are separated from the environment by a cuticle which functions in protection against desiccation and pathogen attack. Recently, we reported on a barley mutant with defect in the 3-KETOACYL-CoA-SYNTHASE (HvKCS6) gene, resulting in reduced coverage of the cuticle with epicuticular waxes. Spores of adapted and non-adapted powdery mildew fungi germinated less frequently on mutant leaves possibly because plant derived signals are missing. We used a shoot and root phenotyping facility to test whether depletion in epicuticular waxes negatively impacts plant performance under water-limiting conditions. While shoots of mutant plants grew slower at well-watered conditions than wild-type plants, they showed an equal or slightly better growth rate at water limitation. Also for roots, differences between mutant and parental line were less prominent at water-limiting as compared to well-watered conditions. Our results challenge the intuitive belief that reduced epicuticular wax might become a drawback at water limitation.
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Key Words
- C, carbon chain length; CER, ECERIFERUM; CUT, REQUIRED FOR CUTICILAR WAX PRODUCTION
- DAS, days after sowing
- GC-MS, gas chromatography-mass spectrometry
- Hv, Hordeum vulgare
- IBG-2, Institute of Biosciences and Geosciences-2 (Forschungszentrum Jülich GmbH)
- KCS, KETOACYL-CoA SYNTHASE
- KETOACYL-CoA SYNTHASE
- VLCFA, very long-chain fatty acid.
- drought stress
- epicuticular wax, cuticle, Hordeum vulgare, phenotyping
- germination
- mlo, mildew resistance locus O
- powdery mildew
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Affiliation(s)
- Denise Weidenbach
- Department of Plant Physiology; RWTH Aachen University; Aachen, Germany
| | - Marcus Jansen
- Institute of Bio- and Geosciences; IBG-2: Plant Sciences; Forschungszentrum Jülich GmbH; Jülich, Germany
| | - Thomas Bodewein
- Institute of Bio- and Geosciences; IBG-2: Plant Sciences; Forschungszentrum Jülich GmbH; Jülich, Germany
| | - Kerstin A Nagel
- Institute of Bio- and Geosciences; IBG-2: Plant Sciences; Forschungszentrum Jülich GmbH; Jülich, Germany
| | - Ulrich Schaffrath
- Department of Plant Physiology; RWTH Aachen University; Aachen, Germany
- Correspondence to: Ulrich Schaffrath;
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Weidenbach D, Jansen M, Franke RB, Hensel G, Weissgerber W, Ulferts S, Jansen I, Schreiber L, Korzun V, Pontzen R, Kumlehn J, Pillen K, Schaffrath U. Evolutionary conserved function of barley and Arabidopsis 3-KETOACYL-CoA SYNTHASES in providing wax signals for germination of powdery mildew fungi. Plant Physiol 2014; 166:1621-33. [PMID: 25201879 PMCID: PMC4226380 DOI: 10.1104/pp.114.246348] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 09/01/2014] [Indexed: 05/18/2023]
Abstract
For plant pathogenic fungi, such as powdery mildews, that survive only on a limited number of host plant species, it is a matter of vital importance that their spores sense that they landed on the right spot to initiate germination as quickly as possible. We investigated a barley (Hordeum vulgare) mutant with reduced epicuticular leaf waxes on which spores of adapted and nonadapted powdery mildew fungi showed reduced germination. The barley gene responsible for the mutant wax phenotype was cloned in a forward genetic screen and identified to encode a 3-KETOACYL-CoA SYNTHASE (HvKCS6), a protein participating in fatty acid elongation and required for synthesis of epicuticular waxes. Gas chromatography-mass spectrometry analysis revealed that the mutant has significantly fewer aliphatic wax constituents with a chain length above C-24. Complementation of the mutant restored wild-type wax and overcame germination penalty, indicating that wax constituents less present on the mutant are a crucial clue for spore germination. Investigation of Arabidopsis (Arabidopsis thaliana) transgenic plants with sense silencing of Arabidopsis REQUIRED FOR CUTICULAR WAX PRODUCTION1, the HvKCS6 ortholog, revealed the same germination phenotype against adapted and nonadapted powdery mildew fungi. Our findings hint to an evolutionary conserved mechanism for sensing of plant surfaces among distantly related powdery mildews that is based on KCS6-derived wax components. Perception of such a signal must have been evolved before the monocot-dicot split took place approximately 150 million years ago.
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Affiliation(s)
- Denise Weidenbach
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Marcus Jansen
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Rochus B Franke
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Goetz Hensel
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Wiebke Weissgerber
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Sylvia Ulferts
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Irina Jansen
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Lukas Schreiber
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Viktor Korzun
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Rolf Pontzen
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Jochen Kumlehn
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Klaus Pillen
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
| | - Ulrich Schaffrath
- Department of Plant Physiology, Rheinisch-Westfaelische Technische Hochschule Aachen University, D-52056 Aachen, Germany (D.W., M.J., S.U., I.J., U.S.);Institute of Biosciences and Geosciences: Plant Sciences, Juelich Plant Phenotyping Centre, Forschungszentrum Jülich GmbH, 52425 Juelich, Germany (M.J.);Ecophysiology of Plants, Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany (R.B.F., L.S.);Plant Reproductive Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Stadt Seeland/OT Gatersleben, Germany (G.H., J.K.);Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, 06120 Halle/Saale, Germany (W.W., K.P.); Cereals Biotechnology,KWS LOCHOW GMBH, 37574 Einbeck, Germany (V.K.); andFormulation Technology, Bayer CropScience AG, 40789 Manheim, Germany (R.P.)
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Zheng Z, Parsons JB, Tangallapally R, Zhang W, Rock CO, Lee RE. Discovery of novel bacterial elongation condensing enzyme inhibitors by virtual screening. Bioorg Med Chem Lett 2014; 24:2585-8. [PMID: 24755430 PMCID: PMC4425204 DOI: 10.1016/j.bmcl.2014.03.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 03/07/2014] [Accepted: 03/12/2014] [Indexed: 10/25/2022]
Abstract
The elongation condensing enzymes in the bacterial fatty acid biosynthesis pathway represent desirable targets for the design of novel, broad-spectrum antimicrobial agents. A series of substituted benzoxazolinones was identified in this study as a novel class of elongation condensing enzyme (FabB and FabF) inhibitors using a two-step virtual screening approach. Structure activity relationships were developed around the benzoxazolinone scaffold showing that N-substituted benzoxazolinones were most active. The benzoxazolinone scaffold has high chemical tractability making this chemotype suitable for further development of bacterial fatty acid synthesis inhibitors.
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Affiliation(s)
- Zhong Zheng
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Joshua B Parsons
- Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Rajendra Tangallapally
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Weixing Zhang
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Charles O Rock
- Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Richard E Lee
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN 38105, USA.
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Oku H, Futamori N, Masuda K, Shimabukuro Y, Omine T, Iwasaki H. Biosynthesis of Branched-chain Fatty Acid inBacilli: FabD (malonyl-CoA:ACP transacylase) Is Not Essential forIn VitroBiosynthesis of Branched-chain Fatty Acids. Biosci Biotechnol Biochem 2014; 67:2106-14. [PMID: 14586097 DOI: 10.1271/bbb.67.2106] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It was found that the partially purified beta-ketoacyl-ACP synthase of Bacillus insolitus did not require the addition of FabD (malonyl-CoA:ACP transacylase, MAT) for the activity assay. This study therefore examined the necessity of FabD protein for in vitro branched-chain fatty acid (BCFA) biosynthesis by crude fatty acid synthetases (FAS) of Bacilli. To discover the involvement of FabD in the BCFA biosynthesis, the protein was removed from the crude FAS by immunoprecipitation. The His-tag fusion protein FabD of Bacillus subtilis was expressed in Escherichia coli and used for the preparation of antibody. The rabbit antibody raised against the expressed fusion protein specifically recognized the FabD in the crude FAS of B. subtilis. Evaluation of the efficacy of the immunoprecipitation showed that a trace of FabD protein was present in the antibody-treated crude FAS. However, this complete removal of FabD from the crude FAS did not abolish its BCFA biosynthesis, but only reduced the level to 50-60% of the control level for acyl-CoA primer and to 80% for alpha-keto-beta-methylvalerate primer. Furthermore, the FabD concentration did not necessarily correlate with the MAT specific activity in the enzyme fractions, suggesting the presence of another enzyme source of MAT activity. This study, therefore, suggests that FabD is not the sole enzyme source of MAT for in vitro BCFA biosynthesis, and implies the existence of a functional connection between fatty acid biosynthesis and another metabolic pathway.
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Affiliation(s)
- Hirosuke Oku
- Division of Molecular Biotechnology, Center of Molecular Bioscience, University of the Ryukyus, Nishihara, Okinawa, Japan.
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Hutter MC, Brengel C, Negri M, Henn C, Zimmer C, Hartmann RW, Empting M, Steinbach A. Mechanistic details for anthraniloyl transfer in PqsD: the initial step in HHQ biosynthesis. J Mol Model 2014; 20:2255. [PMID: 24842325 DOI: 10.1007/s00894-014-2255-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 04/21/2014] [Indexed: 11/25/2022]
Abstract
PqsD mediates the conversion of anthraniloyl-coenzyme A (ACoA) to 2-heptyl-4-hydroxyquinoline (HHQ), a precursor of the Pseudomonas quinolone signal (PQS) molecule. Due to the role of the quinolone signaling pathway of Pseudomonas aeruginosa in the expression of several virulence factors and biofilm formation, PqsD is a potential target for controlling this nosocomial pathogen, which exhibits a low susceptibility to standard antibiotics. PqsD belongs to the β-ketoacyl-ACP synthase family and is similar in structure to homologous FabH enzymes in E. coli and Mycobacterium tuberculosis. Here, we used molecular dynamics simulations to obtain the structural position of the substrate ACoA in the binding pocket of PqsD, and semiempirical molecular orbital calculations to study the reaction mechanism for the catalytic cleavage of ACoA. Our findings suggest a nucleophilic attack of the deprotonated sulfur of Cys112 at the carbonyl carbon of ACoA and a switch in the protonation pattern of His257 whereby Nδ is protonated and the proton of Nε is shifted to the sulfur of CoA during the reaction. This is in agreement with the experimentally determined decreased catalytic activity of the Cys112Ser mutant, whereas the Cys112Ala, His257Phe, and Asn287Ala mutants are all inactive. ESI mass-spectrometric measurements of the Asn287Ala mutant show that anthraniloyl remains covalently bound to Cys112, thus further supporting the inference from our computed mechanism that Asn287 does not take part in the cleavage of ACoA. Since this mutant is inactive, we suggest instead that Asn287 must play an essential role in the subsequent formation of HHQ in vitro.
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Affiliation(s)
- Michael C Hutter
- Center for Bioinformatics, Saarland University, Campus Building E2.1, 66123, Saarbrücken, Germany,
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Vilchèze C, Molle V, Carrère-Kremer S, Leiba J, Mourey L, Shenai S, Baronian G, Tufariello J, Hartman T, Veyron-Churlet R, Trivelli X, Tiwari S, Weinrick B, Alland D, Guérardel Y, Jacobs WR, Kremer L. Phosphorylation of KasB regulates virulence and acid-fastness in Mycobacterium tuberculosis. PLoS Pathog 2014; 10:e1004115. [PMID: 24809459 PMCID: PMC4014462 DOI: 10.1371/journal.ppat.1004115] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 03/28/2014] [Indexed: 11/18/2022] Open
Abstract
Mycobacterium tuberculosis bacilli display two signature features: acid-fast staining and the capacity to induce long-term latent infections in humans. However, the mechanisms governing these two important processes remain largely unknown. Ser/Thr phosphorylation has recently emerged as an important regulatory mechanism allowing mycobacteria to adapt their cell wall structure/composition in response to their environment. Herein, we evaluated whether phosphorylation of KasB, a crucial mycolic acid biosynthetic enzyme, could modulate acid-fast staining and virulence. Tandem mass spectrometry and site-directed mutagenesis revealed that phosphorylation of KasB occurred at Thr334 and Thr336 both in vitro and in mycobacteria. Isogenic strains of M. tuberculosis with either a deletion of the kasB gene or a kasB_T334D/T336D allele, mimicking constitutive phosphorylation of KasB, were constructed by specialized linkage transduction. Biochemical and structural analyses comparing these mutants to the parental strain revealed that both mutant strains had mycolic acids that were shortened by 4–6 carbon atoms and lacked trans-cyclopropanation. Together, these results suggested that in M. tuberculosis, phosphorylation profoundly decreases the condensing activity of KasB. Structural/modeling analyses reveal that Thr334 and Thr336 are located in the vicinity of the catalytic triad, which indicates that phosphorylation of these amino acids would result in loss of enzyme activity. Importantly, the kasB_T334D/T336D phosphomimetic and deletion alleles, in contrast to the kasB_T334A/T336A phosphoablative allele, completely lost acid-fast staining. Moreover, assessing the virulence of these strains indicated that the KasB phosphomimetic mutant was attenuated in both immunodeficient and immunocompetent mice following aerosol infection. This attenuation was characterized by the absence of lung pathology. Overall, these results highlight for the first time the role of Ser/Thr kinase-dependent KasB phosphorylation in regulating the later stages of mycolic acid elongation, with important consequences in terms of acid-fast staining and pathogenicity. Acid-fast staining has been used since 1882 as the hallmark diagnostic test for detecting Mycobacterium tuberculosis, the causative agent of tuberculosis. It has been attributed to the presence of a waxy cell envelope, and primarily to its key components, mycolic acids. Here, we report a new mechanism of regulation in which phosphorylation of KasB, involved in the completion of full-length mycolic acids, leads to shortened mycolic acids and loss of acid-fast staining. Moreover, a M. tuberculosis mutant strain mimicking constitutive phosphorylation of KasB is severely attenuated for growth in both immunocompetent and immunosuppressed mice and fails to cause mortality and pathophysiological symptoms. These results emphasize the critical role of kinase-dependent phosphorylation in the pathogenesis of M. tuberculosis by controlling the mycolic acid chain length. Our study demonstrates the importance of a regulatory mechanism governing acid-fastness and virulence of M. tuberculosis.
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Affiliation(s)
- Catherine Vilchèze
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | - Virginie Molle
- Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS; UMR 5235, Montpellier, France
| | - Séverine Carrère-Kremer
- Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS; UMR 5235, Montpellier, France
| | - Jade Leiba
- Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS; UMR 5235, Montpellier, France
| | - Lionel Mourey
- Institut de Pharmacologie et de Biologie Structurale, CNRS, Toulouse, France; The Université de Toulouse, Université Paul Sabatier, IPBS, Toulouse, France
| | - Shubhada Shenai
- Division of Infectious Diseases, Department of Medicine, and the Ruy V. Lourenco Center for the Study of Emerging and Reemerging Pathogens, New Jersey Medical School, Rutgers Biomedical and Health Sciences, Newark, New Jersey, United States of America
| | - Grégory Baronian
- Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS; UMR 5235, Montpellier, France
| | - Joann Tufariello
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | - Travis Hartman
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | - Romain Veyron-Churlet
- Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS; UMR 5235, Montpellier, France
| | - Xavier Trivelli
- Université Lille 1, Unité de Glycobiologie Structurale et Fonctionnelle, UGSF, Villeneuve d'Ascq, France; CNRS, UMR 8576, Villeneuve d'Ascq, France
| | - Sangeeta Tiwari
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | - Brian Weinrick
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | - David Alland
- Division of Infectious Diseases, Department of Medicine, and the Ruy V. Lourenco Center for the Study of Emerging and Reemerging Pathogens, New Jersey Medical School, Rutgers Biomedical and Health Sciences, Newark, New Jersey, United States of America
| | - Yann Guérardel
- Université Lille 1, Unité de Glycobiologie Structurale et Fonctionnelle, UGSF, Villeneuve d'Ascq, France; CNRS, UMR 8576, Villeneuve d'Ascq, France
| | - William R Jacobs
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | - Laurent Kremer
- Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS; UMR 5235, Montpellier, France; INSERM, DIMNP, Montpellier, France
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Kuo J, Khosla C. The initiation ketosynthase (FabH) is the sole rate-limiting enzyme of the fatty acid synthase of Synechococcus sp. PCC 7002. Metab Eng 2014; 22:53-9. [PMID: 24395007 DOI: 10.1016/j.ymben.2013.12.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 10/28/2013] [Accepted: 12/24/2013] [Indexed: 12/22/2022]
Abstract
Cyanobacteria are Gram-negative bacteria that are desirable hosts for biodiesel production, because they are photosynthetic, relatively fast growing, and can secrete products. We have reconstituted the fatty acid synthase (FAS) of the cyanobacterium Synechococcus sp. PCC 7002 and subjected it to in vitro kinetic analysis. Our data revealed that the overall rate of this metabolic pathway is exclusively limited by the FabH ketosynthase, which initiates product synthesis by condensing malonyl-ACP with acetyl-CoA to form acetoacetyl-ACP. This finding sharply contrasts with our previous findings that the Escherichia coli FAS is predominantly limited by its dehydratase (FabZ) and enoyl reductase (FabI) activities and that FabH activity is not limiting. We therefore reconstituted and analyzed a set of "hybrid" FASs. When the Synechococcus FabH was used to replace its counterpart in the reconstituted E. coli FAS, the resulting synthase was strongly limited by FabH activity. Conversely, replacement of the E. coli FabZ with its Synechococcus homolog dramatically alleviated the dependence of E. coli FAS activity on FabZ. In agreement with this finding, introduction of the E. coli FabH in the Synechococcus FAS virtually eliminated its dependence on this subunit, whereas substitution of the Synechococcus FabZ with its E. coli homolog shifted a substantial fraction of the overall flux control in the Synechococcus FAS to FabZ. Our findings demonstrate that the rate-limiting steps can differ dramatically between closely related bacterial fatty acid synthases, and that such regulatory behavior is fundamentally the property of the controlling enzyme(s).
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Affiliation(s)
- James Kuo
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Chaitan Khosla
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Chemistry, Stanford University, Stanford, CA 94305, USA.
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Kim J, Jung JH, Lee SB, Go YS, Kim HJ, Cahoon R, Markham JE, Cahoon EB, Suh MC. Arabidopsis 3-ketoacyl-coenzyme a synthase9 is involved in the synthesis of tetracosanoic acids as precursors of cuticular waxes, suberins, sphingolipids, and phospholipids. Plant Physiol 2013; 162:567-80. [PMID: 23585652 PMCID: PMC3668053 DOI: 10.1104/pp.112.210450] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 04/09/2013] [Indexed: 05/18/2023]
Abstract
Very-long-chain fatty acids (VLCFAs) with chain lengths from 20 to 34 carbons are involved in diverse biological functions such as membrane constituents, a surface barrier, and seed storage compounds. The first step in VLCFA biosynthesis is the condensation of two carbons to an acyl-coenzyme A, which is catalyzed by 3-ketoacyl-coenzyme A synthase (KCS). In this study, amino acid sequence homology and the messenger RNA expression patterns of 21 Arabidopsis (Arabidopsis thaliana) KCSs were compared. The in planta role of the KCS9 gene, showing higher expression in stem epidermal peels than in stems, was further investigated. The KCS9 gene was ubiquitously expressed in various organs and tissues, including roots, leaves, and stems, including epidermis, silique walls, sepals, the upper portion of the styles, and seed coats, but not in developing embryos. The fluorescent signals of the KCS9::enhanced yellow fluorescent protein construct were merged with those of BrFAD2::monomeric red fluorescent protein, which is an endoplasmic reticulum marker in tobacco (Nicotiana benthamiana) epidermal cells. The kcs9 knockout mutants exhibited a significant reduction in C24 VLCFAs but an accumulation of C20 and C22 VLCFAs in the analysis of membrane and surface lipids. The mutant phenotypes were rescued by the expression of KCS9 under the control of the cauliflower mosaic virus 35S promoter. Taken together, these data demonstrate that KCS9 is involved in the elongation of C22 to C24 fatty acids, which are essential precursors for the biosynthesis of cuticular waxes, aliphatic suberins, and membrane lipids, including sphingolipids and phospholipids. Finally, possible roles of unidentified KCSs are discussed by combining genetic study results and gene expression data from multiple Arabidopsis KCSs.
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Affiliation(s)
- Juyoung Kim
- Department of Bioenergy Science and Technology (J.K., J.H.J., S.B.L., H.J.K., M.C.S.) and Department of Plant Biotechnology (Y.S.G.), College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Republic of Korea; and
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (R.C., J.E.M., E.B.C.)
| | - Jin Hee Jung
- Department of Bioenergy Science and Technology (J.K., J.H.J., S.B.L., H.J.K., M.C.S.) and Department of Plant Biotechnology (Y.S.G.), College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Republic of Korea; and
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (R.C., J.E.M., E.B.C.)
| | - Saet Buyl Lee
- Department of Bioenergy Science and Technology (J.K., J.H.J., S.B.L., H.J.K., M.C.S.) and Department of Plant Biotechnology (Y.S.G.), College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Republic of Korea; and
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (R.C., J.E.M., E.B.C.)
| | - Young Sam Go
- Department of Bioenergy Science and Technology (J.K., J.H.J., S.B.L., H.J.K., M.C.S.) and Department of Plant Biotechnology (Y.S.G.), College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Republic of Korea; and
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (R.C., J.E.M., E.B.C.)
| | | | - Rebecca Cahoon
- Department of Bioenergy Science and Technology (J.K., J.H.J., S.B.L., H.J.K., M.C.S.) and Department of Plant Biotechnology (Y.S.G.), College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Republic of Korea; and
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (R.C., J.E.M., E.B.C.)
| | - Jonathan E. Markham
- Department of Bioenergy Science and Technology (J.K., J.H.J., S.B.L., H.J.K., M.C.S.) and Department of Plant Biotechnology (Y.S.G.), College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Republic of Korea; and
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (R.C., J.E.M., E.B.C.)
| | - Edgar B. Cahoon
- Department of Bioenergy Science and Technology (J.K., J.H.J., S.B.L., H.J.K., M.C.S.) and Department of Plant Biotechnology (Y.S.G.), College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Republic of Korea; and
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (R.C., J.E.M., E.B.C.)
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Smirnova A, Leide J, Riederer M. Deficiency in a very-long-chain fatty acid β-ketoacyl-coenzyme a synthase of tomato impairs microgametogenesis and causes floral organ fusion. Plant Physiol 2013; 161:196-209. [PMID: 23144186 PMCID: PMC3532251 DOI: 10.1104/pp.112.206656] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 11/08/2012] [Indexed: 05/20/2023]
Abstract
Previously, it was shown that β-ketoacyl-coenzyme A synthase ECERIFERUM6 (CER6) is necessary for the biosynthesis of very-long-chain fatty acids with chain lengths beyond C₂₈ in tomato (Solanum lycopersicum) fruits and C₂₆ in Arabidopsis (Arabidopsis thaliana) leaves and the pollen coat. CER6 loss of function in Arabidopsis resulted in conditional male sterility, since pollen coat lipids are responsible for contact-mediated pollen hydration. In tomato, on the contrary, pollen hydration does not rely on pollen coat lipids. Nevertheless, mutation in SlCER6 impairs fertility and floral morphology. Here, the contribution of SlCER6 to the sexual reproduction and flower development of tomato was addressed. Cytological analysis and cross-pollination experiments revealed that the slcer6 mutant has male sterility caused by (1) hampered pollen dispersal and (2) abnormal tapetum development. SlCER6 loss of function provokes a decrease of n- and iso-alkanes with chain lengths of C₂₇ or greater and of anteiso-alkanes with chain lengths of C₂₈ or greater in flower cuticular waxes, but it has no impact on flower cuticle ultrastructure and cutin content. Expression analysis confirmed high transcription levels of SlCER6 in the anther and the petal, preferentially in sites subject to epidermal fusion. Hence, wax deficiency was proposed to be the primary reason for the flower fusion phenomenon in tomato. The SlCER6 substrate specificity was revisited. It might be involved in elongation of not only linear but also branched very-long-chain fatty acids, leading to production of the corresponding alkanes. SlCER6 implements a function in the sexual reproduction of tomato that is different from the one in Arabidopsis: SlCER6 is essential for the regulation of timely tapetum degradation and, consequently, microgametogenesis.
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MESH Headings
- 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/genetics
- 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/metabolism
- Cell Membrane/genetics
- Cell Membrane/metabolism
- Cell Membrane/physiology
- Cell Wall/genetics
- Cell Wall/metabolism
- Cell Wall/physiology
- Cytoplasm/genetics
- Cytoplasm/metabolism
- Flowers/enzymology
- Flowers/physiology
- Flowers/ultrastructure
- Gametogenesis, Plant
- Gene Expression Regulation, Plant
- Genes, Plant
- Germ Cells, Plant/metabolism
- Germ Cells, Plant/physiology
- Germ Cells, Plant/ultrastructure
- Solanum lycopersicum/anatomy & histology
- Solanum lycopersicum/enzymology
- Solanum lycopersicum/genetics
- Solanum lycopersicum/physiology
- Membrane Lipids/metabolism
- Microscopy, Electron, Scanning
- Microscopy, Electron, Transmission
- Phenotype
- Plant Epidermis/metabolism
- Plant Epidermis/ultrastructure
- Plant Infertility
- Plant Proteins/genetics
- Plant Proteins/metabolism
- Pollination
- Reproduction
- Species Specificity
- Substrate Specificity
- Transcription, Genetic
- Waxes/metabolism
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Affiliation(s)
- Anna Smirnova
- Julius-von-Sachs-Institut für Biowissenschaften, Universität Würzburg, D-97082 Wurzburg, Germany.
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Jasinski S, Lécureuil A, Miquel M, Loudet O, Raffaele S, Froissard M, Guerche P. Natural variation in seed very long chain fatty acid content is controlled by a new isoform of KCS18 in Arabidopsis thaliana. PLoS One 2012; 7:e49261. [PMID: 23145136 PMCID: PMC3493540 DOI: 10.1371/journal.pone.0049261] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 10/05/2012] [Indexed: 12/30/2022] Open
Abstract
Oil from oleaginous seeds is mainly composed of triacylglycerols. Very long chain fatty acids (VLCFAs) are major constituents of triacylglycerols in many seed oils and represent valuable feedstock for industrial purposes. To identify genetic factors governing natural variability in VLCFA biosynthesis, a quantitative trait loci (QTL) analysis using a recombinant inbred line population derived from a cross between accessions Bay-0 and Shahdara was performed in Arabidopsis thaliana. Two fatty acid chain length ratio (CLR) QTL were identified, with one major locus, CLR.2, accounting for 77% of the observed phenotypic variation. A fine mapping and candidate gene approach showed that a key enzyme of the fatty acid elongation pathway, the β-ketoacyl-CoA synthase 18 (KCS18), was responsible for the CLR.2 QTL detected between Bay-0 and Shahdara. Association genetics and heterologous expression in yeast cells identified a single point mutation associated with an alteration of KCS18 activity, uncovering the molecular bases for the modulation of VLCFA content in these two natural populations of Arabidopsis. Identification of this kcs18 mutant with altered activity opens new perspectives for the modulation of oil composition in crop plants.
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Affiliation(s)
- Sophie Jasinski
- INRA, UMR1318, Institut Jean-Pierre Bourgin, RD10, Versailles, France.
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41
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Schweizer HP, Choi KH. Characterization of molecular mechanisms controlling fabAB transcription in Pseudomonas aeruginosa. PLoS One 2012; 7:e45646. [PMID: 23056212 PMCID: PMC3462791 DOI: 10.1371/journal.pone.0045646] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Accepted: 08/24/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The FabAB pathway is one of the unsaturated fatty acid (UFA) synthesis pathways for Pseudomonas aeruginosa. It was previously noted that this operon was upregulated in biofilms and repressed by exogenous UFAs. Deletion of a 30 nt fabA upstream sequence, which is conserved in P. aeruginosa, P. putida, and P. syringae, led to a significant decrease in fabA transcription, suggesting positive regulation by an unknown positive regulatory mechanism. METHODS/PRINCIPAL FINDINGS Here, genetic and biochemical approaches were employed to identify a potential fabAB activator. Deletion of candidate genes such as PA1611 or PA1627 was performed to determine if any of these gene products act as a fabAB activator. However, none of these genes were involved in the regulation of fabAB transcription. Use of mariner-based random mutagenesis to screen for fabA activator(s) showed that several genes encoding unknown functions, rpoN and DesA may be involved in fabA regulation, but probably via indirect mechanisms. Biochemical attempts performed did fail to isolate an activator of fabAB operon. CONCLUSION/SIGNIFICANCE The data suggest that fabA expression might not be regulated by protein-binding, but by a distinct mechanism such as a regulatory RNA-based mechanism.
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MESH Headings
- 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/genetics
- 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/metabolism
- 5' Untranslated Regions/genetics
- Amino Acid Sequence
- Bacterial Proteins/genetics
- Bacterial Proteins/metabolism
- Base Sequence
- DNA Transposable Elements/genetics
- Fatty Acid Synthase, Type II/genetics
- Fatty Acid Synthase, Type II/metabolism
- Fatty Acids, Unsaturated/metabolism
- Gene Expression Regulation, Bacterial
- Hydro-Lyases/genetics
- Hydro-Lyases/metabolism
- Molecular Sequence Data
- Mutagenesis, Insertional
- Nucleic Acid Conformation
- Operon
- Promoter Regions, Genetic/genetics
- Pseudomonas aeruginosa/genetics
- Pseudomonas aeruginosa/metabolism
- Pseudomonas putida/genetics
- Pseudomonas putida/metabolism
- Pseudomonas syringae/genetics
- Pseudomonas syringae/metabolism
- RNA, Bacterial/chemistry
- RNA, Bacterial/genetics
- RNA, Bacterial/metabolism
- Regulatory Sequences, Nucleic Acid/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Trans-Activators/genetics
- Trans-Activators/metabolism
- Transcription, Genetic/genetics
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Affiliation(s)
- Herbert P. Schweizer
- Department of Microbiology, Immunology, and Pathology, IDRC at Foothills Campus, Colorado State University, Fort Collins, Colorado, United States of America
| | - Kyoung-Hee Choi
- Department of Oral Microbiology, College of Dentistry, Wonkwang University, Iksan, Chonbuk, South Korea
- * E-mail:
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42
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Gupta M, DeKelver RC, Palta A, Clifford C, Gopalan S, Miller JC, Novak S, Desloover D, Gachotte D, Connell J, Flook J, Patterson T, Robbins K, Rebar EJ, Gregory PD, Urnov FD, Petolino JF. Transcriptional activation of Brassica napus β-ketoacyl-ACP synthase II with an engineered zinc finger protein transcription factor. Plant Biotechnol J 2012; 10:783-791. [PMID: 22520333 DOI: 10.1111/j.1467-7652.2012.00695.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Targeted gene regulation via designed transcription factors has great potential for precise phenotypic modification and acceleration of novel crop trait development. Canola seed oil composition is dictated largely by the expression of genes encoding enzymes in the fatty acid biosynthetic pathway. In the present study, zinc finger proteins (ZFPs) were designed to bind DNA sequences common to two canola β-ketoacyl-ACP Synthase II (KASII) genes downstream of their transcription start site. Transcriptional activators (ZFP-TFs) were constructed by fusing these ZFP DNA-binding domains to the VP16 transcriptional activation domain. Following transformation using Agrobacterium, transgenic events expressing ZFP-TFs were generated and shown to have elevated KASII transcript levels in the leaves of transgenic T(0) plants when compared to 'selectable marker only' controls as well as of T(1) progeny plants when compared to null segregants. In addition, leaves of ZFP-TF-expressing T(1) plants contained statistically significant decreases in palmitic acid (consistent with increased KASII activity) and increased total C18. Similarly, T(2) seed displayed statistically significant decreases in palmitic acid, increased total C18 and reduced total saturated fatty acid contents. These results demonstrate that designed ZFP-TFs can be used to regulate the expression of endogenous genes to elicit specific phenotypic modifications of agronomically relevant traits in a crop species.
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43
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Steinbrecher T, Case DA, Labahn A. Free energy calculations on the binding of novel thiolactomycin derivatives to E. coli fatty acid synthase I. Bioorg Med Chem 2012; 20:3446-53. [PMID: 22560835 DOI: 10.1016/j.bmc.2012.04.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 04/03/2012] [Accepted: 04/07/2012] [Indexed: 11/16/2022]
Abstract
Finding novel antibiotics to combat the rise of drug resistance in harmful bacteria is of enormous importance for human health. Computational drug design can be employed to aid synthetic chemists in the search for new potent inhibitors. In recent years, molecular dynamics based free energy calculations have emerged as a useful tool to accurately calculate receptor binding affinities of novel or modified ligands. While being significantly more demanding in computational resources than simpler docking algorithms, they can be employed to obtain reliable estimates of the effect individual functional groups have on protein-ligand complex binding constants. Beta-ketoacyl [acyl carrier protein] synthase I, KAS I, facilitates a critical chain elongation step in the fatty acid synthesis pathway. Since the bacterial type II lipid synthesis system is fundamentally different from the mammalian type I multi-enzyme complex, this enzyme represents a promising target for the design of specific antibiotics. In this work, we study the binding of several recently synthesized derivatives of the natural KAS I inhibitor thiolactomycin in detail based on atomistic modeling. From extensive thermodynamic integration calculations the effect of changing functional groups on the thiolactone scaffold was determined. Four ligand modifications were predicted to show improved binding to the E. coli enzyme, pointing the way towards the design of thiolactomycin derivatives with binding constants in the nanomolar range.
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Affiliation(s)
- Thomas Steinbrecher
- Institut für Physikalische Chemie, Abteilung Theoretische Chemische Biologie, Universität Karlsruhe, KIT, Kaiserstr. 12, 76131 Karlsruhe, Germany.
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44
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Abstract
Organisms are covered extracellularly with cuticular waxes that consist of various fatty acids. In higher plants, extracellular waxes act as indispensable barriers to protect the plants from physical and biological stresses such as drought and pathogen attacks. However, the effect of fatty acid composition on plant development under normal growth conditions is not well understood. Here we show that the ONION1 (ONI1) gene, which encodes a fatty acid elongase (β-ketoacyl CoA synthase) involved in the synthesis of very-long-chain fatty acids, is required for correct fatty acid composition and normal shoot development in rice. oni1 mutants containing a reduced amount of very-long-chain fatty acids produced very small shoots, with an aberrant outermost epidermal cell layer, and ceased to grow soon after germination. These mutants also showed abnormal expression of a KNOX family homeobox gene. ONI1 was specifically expressed in the outermost cell layer of the shoot apical meristem and developing lateral organs. These results show that fatty acid elongase is required for formation of the outermost cell layer, and this layer is indispensable for entire shoot development in rice.
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Affiliation(s)
- Yukihiro Ito
- Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
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45
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Lewis RA, Nunns L, Thirlway J, Carroll K, Smith CP, Micklefield J. Active site modification of the β-ketoacyl-ACP synthase FabF3 of Streptomyces coelicolor affects the fatty acid chain length of the CDA lipopeptides. Chem Commun (Camb) 2011; 47:1860-2. [PMID: 21135931 DOI: 10.1039/c0cc03444d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
Using site directed mutagenesis we altered an active site residue (Phe107) of the enzyme encoded by fabF3 (SCO3248) in the Streptomyces coelicolor gene cluster required for biosynthesis of the calcium dependent antibiotics (CDAs), successfully generating two novel CDA derivatives comprising truncated (C4) lipid side chains and confirming that fabF3 encodes a KAS-II homologue that is involved in determining CDA fatty acid chain length.
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46
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Affiliation(s)
- Holly Huse
- Department of Molecular Genetics and Microbiology, University of Texas at Austin, Austin, Texas 78712
| | - Marvin Whiteley
- Department of Molecular Genetics and Microbiology, University of Texas at Austin, Austin, Texas 78712
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47
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Wu GZ, Xue HW. Arabidopsis β-ketoacyl-[acyl carrier protein] synthase i is crucial for fatty acid synthesis and plays a role in chloroplast division and embryo development. Plant Cell 2010; 22:3726-44. [PMID: 21081696 PMCID: PMC3015132 DOI: 10.1105/tpc.110.075564] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2010] [Revised: 10/16/2010] [Accepted: 10/30/2010] [Indexed: 05/18/2023]
Abstract
Lipid metabolism plays a pivotal role in cell structure and in multiple plant developmental processes. β-Ketoacyl-[acyl carrier protein] synthase I (KASI) catalyzes the elongation of de novo fatty acid (FA) synthesis. Here, we report the functional characterization of KASI in the regulation of chloroplast division and embryo development. Phenotypic observation of an Arabidopsis thaliana T-DNA insertion mutant, kasI, revealed multiple morphological defects, including chlorotic (in netted patches) and curly leaves, reduced fertility, and semidwarfism. There are only one to five enlarged chloroplasts in the mesophyll cells of chlorotic sectors of young kasI rosette leaves, indicating suppressed chloroplast division under KASI deficiency. KASI deficiency results in a significant change in the polar lipid composition, which causes the suppressed expression of FtsZ and Min system genes, disordered Z-ring placement in the oversized chloroplast, and inhibited polymerization of FtsZ protein at mid-site of the chloroplast in kasI. In addition, KASI deficiency results in disrupted embryo development before the globular stage and dramatically reduces FA levels (~33.6% of the wild type) in seeds. These results demonstrate that de novo FA synthesis is crucial and has pleiotropic effects on plant growth. The polar lipid supply is important for chloroplast division and development, revealing a key function of FA synthesis in plastid development.
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48
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Takami T, Shibata M, Kobayashi Y, Shikanai T. De novo biosynthesis of fatty acids plays critical roles in the response of the photosynthetic machinery to low temperature in Arabidopsis. Plant Cell Physiol 2010; 51:1265-1275. [PMID: 20547590 DOI: 10.1093/pcp/pcq085] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The Arabidopsis thaliana kas3 mutant was isolated based on the hypersensitivity of PSII to low temperature using a Chl fluorescence imaging technique. Chl content was lower in kas3 seedlings cultured at 23 degrees C than in the wild type, but PSII activity was only mildly affected. However, after the chilling treatment at 4 degrees C for 7 d, PSII activity was severely impaired in kas3. PSII was more sensitive to light at 4 degrees C in the presence of lincomycin, suggesting that the kas3 mutation accelerates at least the PSII photodamage. The kas3 mutation causes an amino acid alteration in 3-ketoacyl-ACP synthase III (KasIII), leading to the partial loss of the de novo synthesis pathway for fatty acids in plastids. Consequently, the total fatty acid level was reduced to 75% of the wild-type level in kas3 at 23 degrees C and was further reduced to 60% at 4 degrees C. The composition of fatty acids was also slightly affected in kas3 at both 4 and 23 degrees C. Consistent with the results of the electron transport analysis, the chilling treatment also destabilized PsaA and cytochrome (Cyt) f and D1 in kas3. An analysis of double mutants with pgr1 conditionally defective in Cyt b(6)f activity and with var2 defective in FtsH protease suggested that the kas3 mutation has pleiotropic effects on chloroplast function, probably impacting both the Cyt b(6)f activity and translation in chloroplasts at 23 degrees C. The full activity of KasIII is required for the biogenesis of the intact electron transport machinery in thylakoid membranes and is especially important for the process of responding to low temperature.
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Affiliation(s)
- Tsuneaki Takami
- Graduate School of Agriculture, Kyushu University, Fukuoka, Japan
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49
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González-Mellado D, von Wettstein-Knowles P, Garcés R, Martínez-Force E. The role of beta-ketoacyl-acyl carrier protein synthase III in the condensation steps of fatty acid biosynthesis in sunflower. Planta 2010; 231:1277-89. [PMID: 20221630 DOI: 10.1007/s00425-010-1131-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2009] [Accepted: 02/19/2010] [Indexed: 05/19/2023]
Abstract
The beta-ketoacyl-acyl carrier protein synthase III (KAS III; EC 2.3.1.180) is a condensing enzyme catalyzing the initial step of fatty acid biosynthesis using acetyl-CoA as primer. To determine the mechanisms involved in the biosynthesis of fatty acids in sunflower (Helianthus annuus L.) developing seeds, a cDNA coding for HaKAS III (EF514400) was isolated, cloned and sequenced. Its protein sequence is as much as 72% identical to other KAS III-like ones such as those from Perilla frutescens, Jatropha curcas, Ricinus communis or Cuphea hookeriana. Phylogenetic study of the HaKAS III homologous proteins infers its origin from cyanobacterial ancestors. A genomic DNA gel blot analysis revealed that HaKAS III is a single copy gene. Expression levels of this gene, examined by Q-PCR, revealed higher levels in developing seeds storing oil than in leaves, stems, roots or seedling cotyledons. Heterologous expression of HaKAS III in Escherichia coli altered their fatty acid content and composition implying an interaction of HaKAS III with the bacterial FAS complex. Testing purified HaKAS III recombinant protein by adding to a reconstituted E. coli FAS system lacking condensation activity revealed a novel substrate specificity. In contrast to all hitherto characterized plant KAS IIIs, the activities of which are limited to the first cycles of intraplastidial fatty acid biosynthesis yielding C6 chains, HaKAS III participates in at least four cycles resulting in C10 chains.
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MESH Headings
- 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/chemistry
- 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/genetics
- 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/isolation & purification
- 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/metabolism
- Amino Acid Sequence
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- DNA, Plant/genetics
- Electrophoresis, Polyacrylamide Gel
- Escherichia coli
- Fatty Acids/biosynthesis
- Gene Expression Profiling
- Gene Expression Regulation, Plant
- Genome, Plant/genetics
- Helianthus/enzymology
- Helianthus/genetics
- Models, Molecular
- Molecular Sequence Data
- Phylogeny
- Protein Structure, Secondary
- Recombinant Proteins/metabolism
- Seeds/enzymology
- Seeds/genetics
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
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50
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Julotok M, Singh AK, Gatto C, Wilkinson BJ. Influence of fatty acid precursors, including food preservatives, on the growth and fatty acid composition of Listeria monocytogenes at 37 and 10degreesC. Appl Environ Microbiol 2010; 76:1423-32. [PMID: 20048057 PMCID: PMC2832362 DOI: 10.1128/aem.01592-09] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Accepted: 12/14/2009] [Indexed: 11/20/2022] Open
Abstract
Listeria monocytogenes is a food-borne pathogen that grows at refrigeration temperatures and increases its content of anteiso-C(15:0) fatty acid, which is believed to be a homeoviscous adaptation to ensure membrane fluidity, at these temperatures. As a possible novel approach for control of the growth of the organism, the influences of various fatty acid precursors, including branched-chain amino acids and branched- and straight-chain carboxylic acids, some of which are also well-established food preservatives, on the growth and fatty acid composition of the organism at 37 degrees C and 10 degrees C were studied in order to investigate whether the organism could be made to synthesize fatty acids that would result in impaired growth at low temperatures. The results indicate that the fatty acid composition of L. monocytogenes could be modulated by the feeding of branched-chain amino acid, C(4), C(5), and C(6) branched-chain carboxylic acid, and C(3) and C(4) straight-chain carboxylic acid fatty acid precursors, but the growth-inhibitory effects of several preservatives were independent of effects on fatty acid composition, which were minor in the case of preservatives metabolized via acetyl coenzyme A. The ability of a precursor to modify fatty acid composition was probably a reflection of the substrate specificities of the first enzyme, FabH, in the condensation of primers of fatty acid biosynthesis with malonyl acyl carrier protein.
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Affiliation(s)
- Mudcharee Julotok
- Microbiology Group, School of Biological Sciences, Illinois State University, Normal, Illinois 61790
| | - Atul K. Singh
- Microbiology Group, School of Biological Sciences, Illinois State University, Normal, Illinois 61790
| | - Craig Gatto
- Microbiology Group, School of Biological Sciences, Illinois State University, Normal, Illinois 61790
| | - Brian J. Wilkinson
- Microbiology Group, School of Biological Sciences, Illinois State University, Normal, Illinois 61790
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