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Lopez-Ortiz C, Reddy UK, Zhang C, Natarajan P, Nimmakayala P, Benedito VA, Fabian M, Stommel J. QTL and PACE analyses identify candidate genes for anthracnose resistance in tomato. FRONTIERS IN PLANT SCIENCE 2023; 14:1200999. [PMID: 37615029 PMCID: PMC10443646 DOI: 10.3389/fpls.2023.1200999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 07/17/2023] [Indexed: 08/25/2023]
Abstract
Anthracnose, caused by the fungal pathogen Colletotrichum spp., is one of the most significant tomato diseases in the United States and worldwide. No commercial cultivars with anthracnose resistance are available, limiting resistant breeding. Cultivars with genetic resistance would significantly reduce crop losses, reduce the use of fungicides, and lessen the risks associated with chemical application. A recombinant inbred line (RIL) mapping population (N=243) has been made from a cross between the susceptible US28 cultivar and the resistant but semiwild and small-fruited 95L368 to identify quantitative trait loci (QTLs) associated with anthracnose resistance. The RIL population was phenotyped for resistance by inoculating ripe field-harvested tomato fruits with Colletotrichum coccodes for two seasons. In this study, we identified twenty QTLs underlying resistance, with a range of phenotypic variance of 4.5 to 17.2% using a skeletal linkage map and a GWAS. In addition, a QTLseq analysis was performed using deep sequencing of extreme bulks that validated QTL positions identified using traditional mapping and resolved candidate genes underlying various QTLs. We further validated AP2-like ethylene-responsive transcription factor, N-alpha-acetyltransferase (NatA), cytochrome P450, amidase family protein, tetratricopeptide repeat, bHLH transcription factor, and disease resistance protein RGA2-like using PCR allelic competitive extension (PACE) genotyping. PACE assays developed in this study will enable high-throughput screening for use in anthracnose resistance breeding in tomato.
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Affiliation(s)
- Carlos Lopez-Ortiz
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV, United States
| | - Umesh K. Reddy
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV, United States
| | - Chong Zhang
- The Genetic Improvement for Fruits & Vegetables Laboratory, United States Department of Agriculture, Agricultural Research Service, Beltsville, MD, United States
| | - Purushothaman Natarajan
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV, United States
| | - Padma Nimmakayala
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV, United States
| | | | - Matthew Fabian
- The Genetic Improvement for Fruits & Vegetables Laboratory, United States Department of Agriculture, Agricultural Research Service, Beltsville, MD, United States
| | - John Stommel
- The Genetic Improvement for Fruits & Vegetables Laboratory, United States Department of Agriculture, Agricultural Research Service, Beltsville, MD, United States
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Yang Q, Song Z, Li X, Hou Y, Xu T, Wu S. Lichen-Derived Actinomycetota: Novel Taxa and Bioactive Metabolites. Int J Mol Sci 2023; 24:ijms24087341. [PMID: 37108503 PMCID: PMC10138632 DOI: 10.3390/ijms24087341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/13/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
Actinomycetes are essential sources of numerous bioactive secondary metabolites with diverse chemical and bioactive properties. Lichen ecosystems have piqued the interest of the research community due to their distinct characteristics. Lichen is a symbiont of fungi and algae or cyanobacteria. This review focuses on the novel taxa and diverse bioactive secondary metabolites identified between 1995 and 2022 from cultivable actinomycetota associated with lichens. A total of 25 novel actinomycetota species were reported following studies of lichens. The chemical structures and biological activities of 114 compounds derived from the lichen-associated actinomycetota are also summarized. These secondary metabolites were classified into aromatic amides and amines, diketopiperazines, furanones, indole, isoflavonoids, linear esters and macrolides, peptides, phenolic derivatives, pyridine derivatives, pyrrole derivatives, quinones, and sterols. Their biological activities included anti-inflammatory, antimicrobial, anticancer, cytotoxic, and enzyme-inhibitory actions. In addition, the biosynthetic pathways of several potent bioactive compounds are summarized. Thus, lichen actinomycetes demonstrate exceptional abilities in the discovery of new drug candidates.
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Affiliation(s)
- Qingrong Yang
- Yunnan Institute of Microbiology, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Zhiqiang Song
- Yunnan Institute of Microbiology, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Xinpeng Li
- Yunnan Institute of Microbiology, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Yage Hou
- Yunnan Institute of Microbiology, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Tangchang Xu
- Yunnan Institute of Microbiology, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Shaohua Wu
- Yunnan Institute of Microbiology, School of Life Sciences, Yunnan University, Kunming 650091, China
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3
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Beyond the Usual Suspects: Physiological Roles of the Arabidopsis Amidase Signature (AS) Superfamily Members in Plant Growth Processes and Stress Responses. Biomolecules 2021; 11:biom11081207. [PMID: 34439873 PMCID: PMC8393822 DOI: 10.3390/biom11081207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 12/25/2022] Open
Abstract
The diversification of land plants largely relies on their ability to cope with constant environmental fluctuations, which negatively impact their reproductive fitness and trigger adaptive responses to biotic and abiotic stresses. In this limiting landscape, cumulative research attention has centred on deepening the roles of major phytohormones, mostly auxins, together with brassinosteroids, jasmonates, and abscisic acid, despite the signaling networks orchestrating the crosstalk among them are so far only poorly understood. Accordingly, this review focuses on the Arabidopsis Amidase Signature (AS) superfamily members, with the aim of highlighting the hitherto relatively underappreciated functions of AMIDASE1 (AMI1) and FATTY ACID AMIDE HYDROLASE (FAAH), as comparable coordinators of the growth-defense trade-off, by balancing auxin and ABA homeostasis through the conversion of their likely bioactive substrates, indole-3-acetamide and N-acylethanolamine.
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Transcriptome analysis of early stages of sorghum grain mold disease reveals defense regulators and metabolic pathways associated with resistance. BMC Genomics 2021; 22:295. [PMID: 33888060 PMCID: PMC8063297 DOI: 10.1186/s12864-021-07609-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/22/2021] [Indexed: 12/26/2022] Open
Abstract
Background Sorghum grain mold is the most important disease of the crop. The disease results from simultaneous infection of the grain by multiple fungal species. Host responses to these fungi and the underlying molecular and cellular processes are poorly understood. To understand the genetic, molecular and biochemical components of grain mold resistance, transcriptome profiles of the developing grain of resistant and susceptible sorghum genotypes were studied. Results The developing kernels of grain mold resistant RTx2911 and susceptible RTx430 sorghum genotypes were inoculated with a mixture of fungal pathogens mimicking the species complexity of the disease under natural infestation. Global transcriptome changes corresponding to multiple molecular and cellular processes, and biological functions including defense, secondary metabolism, and flavonoid biosynthesis were observed with differential regulation in the two genotypes. Genes encoding pattern recognition receptors (PRRs), regulators of growth and defense homeostasis, antimicrobial peptides, pathogenesis-related proteins, zein seed storage proteins, and phytoalexins showed increased expression correlating with resistance. Notably, SbLYK5 gene encoding an orthologue of chitin PRR, defensin genes SbDFN7.1 and SbDFN7.2 exhibited higher expression in the resistant genotype. The SbDFN7.1 and SbDFN7.2 genes are tightly linked and transcribed in opposite orientation with a likely common bidirectional promoter. Interestingly, increased expression of JAZ and other transcriptional repressors were observed that suggested the tight regulation of plant defense and growth. The data suggest a pathogen inducible defense system in the developing grain of sorghum that involves the chitin PRR, MAPKs, key transcription factors, downstream components regulating immune gene expression and accumulation of defense molecules. We propose a model through which the biosynthesis of 3-deoxyanthocynidin phytoalexins, defensins, PR proteins, other antimicrobial peptides, and defense suppressing proteins are regulated by a pathogen inducible defense system in the developing grain. Conclusions The transcriptome data from a rarely studied tissue shed light into genetic, molecular, and biochemical components of disease resistance and suggested that the developing grain shares conserved immune response mechanisms but also components uniquely enriched in the grain. Resistance was associated with increased expression of genes encoding regulatory factors, novel grain specific antimicrobial peptides including defensins and storage proteins that are potential targets for crop improvement. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07609-y.
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Wu H, Yang J, Shen P, Li Q, Wu W, Jiang X, Qin L, Huang J, Cao X, Qi F. High-Level Production of Indole-3-acetic Acid in the Metabolically Engineered Escherichia coli. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:1916-1924. [PMID: 33541074 DOI: 10.1021/acs.jafc.0c08141] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Indole-3-acetic acid (IAA) is a critical plant hormone that regulates cell division, development, and metabolism. IAA synthesis in plants and plant-associated microorganisms cannot fulfill the requirement for large-scale agricultural production. Here, two novel IAA biosynthesis pathways, tryptamine (TAM) and indole-3-acetamide (IAM), were developed for IAA production by whole-cell catalysis and de novo biosynthesis in an engineered Escherichia coli MG1655. When 10 g/L l-tryptophan was used as a substrate, an MIA-6 strain containing a heterologous IAM pathway had the highest IAA titer of 7.10 g/L (1.34 × 103 mg/g DCW), which was 98.4 times more than MTAI-5 containing the TAM pathway by whole-cell catalysis. De novo IAA biosynthesis was optimized by improving NAD(P)H availability, resulting in an increased IAA titer of 906 mg/L obtained by the MGΔadhE::icd strain, which is 29.7% higher than the control. These strategies exhibit the potential for IAA production in engineered E. coli and possible industrial applications.
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Affiliation(s)
- Hongxuan Wu
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, Fujian, China
| | - Jinhua Yang
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, Fujian, China
| | - Peijie Shen
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, Fujian, China
| | - Qingchen Li
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation and Provincial University Engineering Research Center of Industrial Biocatalysis, Fujian Normal University, Fuzhou, Fujian 350117, China
| | - Weibin Wu
- Fujian Vocational College of Bio-engineering, Fuzhou, Fujian 350002, China
| | - Xianzhang Jiang
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, Fujian, China
| | - Lina Qin
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, Fujian, China
| | - Jianzhong Huang
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, Fujian, China
| | - Xiao Cao
- Fujian Vocational College of Bio-engineering, Fuzhou, Fujian 350002, China
| | - Feng Qi
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, Fujian, China
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6
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Zhang L, Luo P, Bai J, Wu L, Di DW, Liu HQ, Li JJ, Liu YL, Khaskheli AJ, Zhao CM, Guo GQ. Function of histone H2B monoubiquitination in transcriptional regulation of auxin biosynthesis in Arabidopsis. Commun Biol 2021; 4:206. [PMID: 33589721 PMCID: PMC7884795 DOI: 10.1038/s42003-021-01733-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 01/13/2021] [Indexed: 11/09/2022] Open
Abstract
The auxin IAA is a vital plant hormone in controlling growth and development, but our knowledge about its complicated biosynthetic pathways and molecular regulation are still limited and fragmentary. cytokinin induced root waving 2 (ckrw2) was isolated as one of the auxin-deficient mutants in a large-scale forward genetic screen aiming to find more genes functioning in auxin homeostasis and/or its regulation. Here we show that CKRW2 is identical to Histone Monoubiquitination 1 (HUB1), a gene encoding an E3 ligase required for histone H2B monoubiquitination (H2Bub1) in Arabidopsis. In addition to pleiotropic defects in growth and development, loss of CKRW2/HUB1 function also led to typical auxin-deficient phenotypes in roots, which was associated with significantly lower expression levels of several functional auxin synthetic genes, namely TRP2/TSB1, WEI7/ASB1, YUC7 and AMI1. Corresponding defects in H2Bub1 were detected in the coding regions of these genes by chromatin immunoprecipitation (ChIP) analysis, indicating the involvement of H2Bub1 in regulating auxin biosynthesis. Importantly, application of exogenous cytokinin (CK) could stimulate CKRW2/HUB1 expression, providing an epigenetic avenue for CK to regulate the auxin homeostasis. Our results reveal a previously unknown mechanism for regulating auxin biosynthesis via HUB1/2-mediated H2Bub1 at the chromatin level.
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Affiliation(s)
- Li Zhang
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China
| | - Pan Luo
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China.,College of Life Science and Technology, Gansu Agricultural University, Lanzhou, Gansu, P.R. China
| | - Jie Bai
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China
| | - Lei Wu
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China
| | - Dong-Wei Di
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China.,State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, P.R. China
| | - Hai-Qing Liu
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China
| | - Jing-Jing Li
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China
| | - Ya-Li Liu
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China
| | - Allah Jurio Khaskheli
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China
| | - Chang-Ming Zhao
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China. .,State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, P.R. China.
| | - Guang-Qin Guo
- Institute of Cell Biology and MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, P.R. China.
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7
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Pérez-Alonso MM, Ortiz-García P, Moya-Cuevas J, Lehmann T, Sánchez-Parra B, Björk RG, Karim S, Amirjani MR, Aronsson H, Wilkinson MD, Pollmann S. Endogenous indole-3-acetamide levels contribute to the crosstalk between auxin and abscisic acid, and trigger plant stress responses in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:459-475. [PMID: 33068437 PMCID: PMC7853601 DOI: 10.1093/jxb/eraa485] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 10/13/2020] [Indexed: 05/13/2023]
Abstract
The evolutionary success of plants relies to a large extent on their extraordinary ability to adapt to changes in their environment. These adaptations require that plants balance their growth with their stress responses. Plant hormones are crucial mediators orchestrating the underlying adaptive processes. However, whether and how the growth-related hormone auxin and the stress-related hormones jasmonic acid, salicylic acid, and abscisic acid (ABA) are coordinated remains largely elusive. Here, we analyse the physiological role of AMIDASE 1 (AMI1) in Arabidopsis plant growth and its possible connection to plant adaptations to abiotic stresses. AMI1 contributes to cellular auxin homeostasis by catalysing the conversion of indole-acetamide into the major plant auxin indole-3-acetic acid. Functional impairment of AMI1 increases the plant's stress status rendering mutant plants more susceptible to abiotic stresses. Transcriptomic analysis of ami1 mutants disclosed the reprogramming of a considerable number of stress-related genes, including jasmonic acid and ABA biosynthesis genes. The ami1 mutants exhibit only moderately repressed growth but an enhanced ABA accumulation, which suggests a role for AMI1 in the crosstalk between auxin and ABA. Altogether, our results suggest that AMI1 is involved in coordinating the trade-off between plant growth and stress responses, balancing auxin and ABA homeostasis.
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Affiliation(s)
- Marta-Marina Pérez-Alonso
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) – Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Pozuelo de Alarcón, Spain
| | - Paloma Ortiz-García
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) – Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Pozuelo de Alarcón, Spain
| | - José Moya-Cuevas
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) – Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Pozuelo de Alarcón, Spain
| | - Thomas Lehmann
- Lehrstuhl für Pflanzenphysiologie, Ruhr-Universität Bochum, Bochum, Germany
| | - Beatriz Sánchez-Parra
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) – Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Pozuelo de Alarcón, Spain
- Current address: Max-Planck-Institute for Chemistry, Mainz, Germany
| | - Robert G Björk
- Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden
- Gothenburg Global Biodiversity Centre, Gothenburg, Sweden
| | - Sazzad Karim
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
- Department of Infectious Diseases, Institute of Biomedicine, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Mohammad R Amirjani
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
- Current address: Department of Biology, Arak University, Arak, Iran
| | - Henrik Aronsson
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Mark D Wilkinson
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) – Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Pozuelo de Alarcón, Spain
| | - Stephan Pollmann
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) – Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Pozuelo de Alarcón, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid (UPM), Madrid, Spain
- Correspondence:
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8
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González-Magaña A, Sainz-Polo MÁ, Pretre G, Çapuni R, Lucas M, Altuna J, Montánchez I, Fucini P, Albesa-Jové D. Structural insights into Pseudomonas aeruginosaType six secretion system exported effector 8. J Struct Biol 2020; 212:107651. [PMID: 33096229 DOI: 10.1016/j.jsb.2020.107651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 10/13/2020] [Accepted: 10/15/2020] [Indexed: 12/24/2022]
Abstract
Recent reports indicate that the Type six secretion system exported effector 8 (Tse8) is a cytoactive effector secreted by the Type VI secretion system (T6SS) of the human pathogen Pseudomonas aeruginosa. The T6SS is a nanomachine that assembles inside of the bacteria and injects effectors/toxins into target cells, providing a fitness advantage over competing bacteria and facilitating host colonisation. Here we present the first crystal structure of Tse8 revealing that it conserves the architecture of the catalytic triad Lys84-transSer162-Ser186 that characterises members of the Amidase Signature superfamily. Furthermore, using binding affinity experiments, we show that the interaction of phenylmethylsulfonyl fluoride (PMSF) to Tse8 is dependent on the putative catalytic residue Ser186, providing support for its nucleophilic reactivity. This work thus demonstrates that Tse8 belongs to the Amidase Signature (AS) superfamily. Furthermore, it highlights Tse8 similarity to two family members: the Stenotrophomonas maltophilia Peptide Amidase and the Glutamyl-tRNAGln amidotransferase subunit A from Staphylococcus aureus.
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Affiliation(s)
- Amaia González-Magaña
- Instituto Biofisika (UPV/EHU, CSIC), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB) and Departamento de Bioquímica y Biología Molecular, University of the Basque Country, 48940 Leioa, Spain
| | - M Ángela Sainz-Polo
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 48160 Derio, Spain
| | - Gabriela Pretre
- Instituto Biofisika (UPV/EHU, CSIC), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB) and Departamento de Bioquímica y Biología Molecular, University of the Basque Country, 48940 Leioa, Spain
| | - Retina Çapuni
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 48160 Derio, Spain
| | - María Lucas
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Consejo Superior de Investigaciones Científicas (CSIC)-Universidad de Cantabria. Santander, 39011 Cantabria, Spain
| | - Jon Altuna
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 48160 Derio, Spain
| | - Itxaso Montánchez
- Departamento de Inmunología, Microbiología y Parasitología, University of the Basque Country, 48940 Leioa, Spain
| | - Paola Fucini
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
| | - David Albesa-Jové
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 48160 Derio, Spain; Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain.
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9
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Andi B, Soares AS, Shi W, Fuchs MR, McSweeney S, Liu Q. Structure of the dihydrolipoamide succinyltransferase catalytic domain from Escherichia coli in a novel crystal form: a tale of a common protein crystallization contaminant. Acta Crystallogr F Struct Biol Commun 2019; 75:616-624. [PMID: 31475929 PMCID: PMC6718150 DOI: 10.1107/s2053230x19011488] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 08/15/2019] [Indexed: 12/12/2022] Open
Abstract
The crystallization of amidase, the ultimate enzyme in the Trp-dependent auxin-biosynthesis pathway, from Arabidopsis thaliana was attempted using protein samples with at least 95% purity. Cube-shaped crystals that were assumed to be amidase crystals that belonged to space group I4 (unit-cell parameters a = b = 128.6, c = 249.7 Å) were obtained and diffracted to 3.0 Å resolution. Molecular replacement using structures from the PDB containing the amidase signature fold as search models was unsuccessful in yielding a convincing solution. Using the Sequence-Independent Molecular replacement Based on Available Databases (SIMBAD) program, it was discovered that the structure corresponded to dihydrolipoamide succinyltransferase from Escherichia coli (PDB entry 1c4t), which is considered to be a common crystallization contaminant protein. The structure was refined to an Rwork of 23.0% and an Rfree of 27.2% at 3.0 Å resolution. The structure was compared with others of the same protein deposited in the PDB. This is the first report of the structure of dihydrolipoamide succinyltransferase isolated without an expression tag and in this novel crystal form.
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Affiliation(s)
- Babak Andi
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973-5000, USA
| | - Alexei S. Soares
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973-5000, USA
| | - Wuxian Shi
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973-5000, USA
| | - Martin R. Fuchs
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973-5000, USA
| | - Sean McSweeney
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973-5000, USA
| | - Qun Liu
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973-5000, USA
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973-5000, USA
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10
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Nelson DL, Applegate GA, Beio ML, Graham DL, Berkowitz DB. Human serine racemase structure/activity relationship studies provide mechanistic insight and point to position 84 as a hot spot for β-elimination function. J Biol Chem 2017; 292:13986-14002. [PMID: 28696262 DOI: 10.1074/jbc.m117.777904] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 06/26/2017] [Indexed: 11/06/2022] Open
Abstract
There is currently great interest in human serine racemase, the enzyme responsible for producing the NMDA co-agonist d-serine. Reported correlation of d-serine levels with disorders including Alzheimer's disease, ALS, and ischemic brain damage (elevated d-serine) and schizophrenia (reduced d-serine) has further piqued this interest. Reported here is a structure/activity relationship study of position Ser84, the putative re-face base. In the most extreme case of functional reprogramming, the S84D mutant displays a dramatic reversal of β-elimination substrate specificity in favor of l-serine over the normally preferred l-serine-O-sulfate (∼1200-fold change in kcat/Km ratios) and l (l-THA; ∼5000-fold change in kcat/Km ratios) alternative substrates. On the other hand, the S84T (which performs l-Ser racemization activity), S84A (good kcat but high Km for l-THA elimination), and S84N mutants (nearly WT efficiency for l-Ser elimination) displayed intermediate activity, all showing a preference for the anionic substrates, but generally attenuated compared with the native enzyme. Inhibition studies with l-erythro-β-hydroxyaspartate follow this trend, with both WT serine racemase and the S84N mutant being competitively inhibited, with Ki = 31 ± 1.5 μm and 1.5 ± 0.1 mm, respectively, and the S84D being inert to inhibition. Computational modeling pointed to a key role for residue Arg-135 in binding and properly positioning the l-THA and l-serine-O-sulfate substrates and the l-erythro-β-hydroxyaspartate inhibitor. Examination of available sequence data suggests that Arg-135 may have originated for l-THA-like β-elimination function in earlier evolutionary variants, and examination of available structural data suggests that a Ser84-H2O-Lys114 hydrogen-bonding network in human serine racemase lowers the pKa of the Ser84re-face base.
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Affiliation(s)
- David L Nelson
- From the Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588
| | - Greg A Applegate
- From the Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588
| | - Matthew L Beio
- From the Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588
| | - Danielle L Graham
- From the Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588
| | - David B Berkowitz
- From the Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588.
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11
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Cerqueira NMFSA, Moorthy H, Fernandes PA, Ramos MJ. The mechanism of the Ser-(cis)Ser-Lys catalytic triad of peptide amidases. Phys Chem Chem Phys 2017; 19:12343-12354. [PMID: 28453015 DOI: 10.1039/c7cp00277g] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper, we report a theoretical investigation of the catalytic mechanism of peptide amidases that involve a Ser-(cis)Ser-Lys catalytic triad. Previous suggestions propose that these enzymes should follow a distinct catalytic mechanism from the one that is present in the classic Ser-His-Asp catalytic triad. The theoretical and computational results obtained in this work indicate the opposite idea, showing that both mechanisms are very similar and only few differences are observed between both reactions. The results reveal that the different alignment of the Ser-(cis)Ser-Lys catalytic triad in relation to the classical Ser-His-Asp triad may provide a better stabilisation of the reaction intermediates, and therefore make these enzymes catalytically more efficient. The catalytic mechanism has been determined at the M06-2X/6-311++G**//B3LYP/6-31G* level of theory and requires five sequential steps instead of the two that are generally proposed: (i) nucleophilic attack of serine on the carbonyl group of the substrate, forming the first tetrahedral intermediate, (ii) formation of an acyl-enzyme complex, (ii) release of an ammonia product, (iv) nucleophilic attack of a water molecule forming the second tetrahedral intermediate, and (iv) the release of the product of the reaction, the carboxylic acid. The computational results suggest that the rate-limiting step is the first one that requires an activation free energy of 15.93 kcal mol-1. This result agrees very well with the available experimental data that predict a reaction rate of 2200 s-1, which corresponds to a free energy barrier of 14 kcal mol-1.
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Affiliation(s)
- N M F S A Cerqueira
- UCIBO-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal.
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Mishra P, Kaur S, Sharma AN, Jolly RS. Characterization of an Indole-3-Acetamide Hydrolase from Alcaligenes faecalis subsp. parafaecalis and Its Application in Efficient Preparation of Both Enantiomers of Chiral Building Block 2,3-Dihydro-1,4-Benzodioxin-2-Carboxylic Acid. PLoS One 2016; 11:e0159009. [PMID: 27391673 PMCID: PMC4938524 DOI: 10.1371/journal.pone.0159009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 06/25/2016] [Indexed: 11/19/2022] Open
Abstract
Both the enantiomers of 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid are valuable chiral synthons for enantiospecific synthesis of therapeutic agents such as (S)-doxazosin mesylate, WB 4101, MKC 242, 2,3-dihydro-2-hydroxymethyl-1,4-benzodioxin, and N-[2,4-oxo-1,3-thiazolidin-3-yl]-2,3-dihydro-1,4-benzodioxin-2-carboxamide. Pharmaceutical applications require these enantiomers in optically pure form. However, currently available methods suffer from one drawback or other, such as low efficiency, uncommon and not so easily accessible chiral resolving agent and less than optimal enantiomeric purity. Our interest in finding a biocatalyst for efficient production of enantiomerically pure 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid lead us to discover an amidase activity from Alcaligenes faecalis subsp. parafaecalis, which was able to kinetically resolve 2,3-dihydro-1,4-benzodioxin-2-carboxyamide with E value of >200. Thus, at about 50% conversion, (R)-2,3-dihydro-1,4-benzodioxin-2-carboxylic acid was produced in >99% e.e. The remaining amide had (S)-configuration and 99% e.e. The amide and acid were easily separated by aqueous (alkaline)-organic two phase extraction method. The same amidase was able to catalyse, albeit at much lower rate the hydrolysis of (S)-amide to (S)-acid without loss of e.e. The amidase activity was identified as indole-3-acetamide hydrolase (IaaH). IaaH is known to catalyse conversion of indole-3-acetamide (IAM) to indole-3-acetic acid (IAA), which is phytohormone of auxin class and is widespread among plants and bacteria that inhabit plant rhizosphere. IaaH exhibited high activity for 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which was about 65% compared to its natural substrate, indole-3-acetamide. The natural substrate for IaaH indole-3-acetamide shared, at least in part a similar bicyclic structure with 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which may account for high activity of enzyme towards this un-natural substrate. To the best of our knowledge this is the first application of IaaH in production of industrially important molecules.
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Affiliation(s)
- Pradeep Mishra
- Department of Bioorganic Chemistry, CSIR-Institute of Microbial Technology, Sector 39, Chandigarh, India
| | - Suneet Kaur
- Department of Bioorganic Chemistry, CSIR-Institute of Microbial Technology, Sector 39, Chandigarh, India
| | - Amar Nath Sharma
- Department of Bioorganic Chemistry, CSIR-Institute of Microbial Technology, Sector 39, Chandigarh, India
| | - Ravinder S. Jolly
- Department of Bioorganic Chemistry, CSIR-Institute of Microbial Technology, Sector 39, Chandigarh, India
- * E-mail:
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Xu HH, Liu SJ, Song SH, Wang RX, Wang WQ, Song SQ. Proteomics analysis reveals distinct involvement of embryo and endosperm proteins during seed germination in dormant and non-dormant rice seeds. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 103:219-42. [PMID: 27035683 DOI: 10.1016/j.plaphy.2016.03.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 03/01/2016] [Accepted: 03/04/2016] [Indexed: 05/09/2023]
Abstract
Seed germination is a complex trait which is influenced by many genetic, endogenous and environmental factors, but the key event(s) associated with seed germination are still poorly understood. In present study, the non-dormant cultivated rice Yannong S and the dormant Dongxiang wild rice seeds were used as experimental materials, we comparatively investigated the water uptake, germination time course, and the differential proteome of the effect of embryo and endosperm on germination of these two types of seeds. A total of 231 and 180 protein spots in embryo and endosperm, respectively, showed a significant change in abundance during germination. We observed that the important proteins associated with seed germination included those involved in metabolism, energy production, protein synthesis and destination, storage protein, cell growth and division, signal transduction, cell defense and rescue. The contribution of embryo and endosperm to seed germination is different. In embryo, the proteins involved in amino acid activation, sucrose cleavage, glycolysis, fermentation and protein synthesis increased; in endosperm, the proteins involved in sucrose cleavage and glycolysis decreased, and those with ATP and CoQ synthesis and proteolysis increased. Our results provide some new knowledge to understand further the mechanism of seed germination.
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Affiliation(s)
- Heng-Heng Xu
- Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Shu-Jun Liu
- Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Shun-Hua Song
- Beijing Vegetable Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China
| | - Rui-Xia Wang
- College of Life Science, Linyi University, Linyi 276005, China
| | - Wei-Qing Wang
- Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Song-Quan Song
- Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
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Hydrazidase, a novel amidase signature enzyme that hydrolyzes acylhydrazides. J Bacteriol 2015; 197:1115-24. [PMID: 25583978 DOI: 10.1128/jb.02443-14] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The degradation mechanisms of natural and artificial hydrazides have been elucidated. Here we screened and isolated bacteria that utilize the acylhydrazide 4-hydroxybenzoic acid 1-phenylethylidene hydrazide (HBPH) from soils. Physiological and phylogenetic studies identified one bacterium as Microbacterium sp. strain HM58-2, from which we purified intracellular hydrazidase, cloned its gene, and prepared recombinant hydrazidase using an Escherichia coli expression system. The Microbacterium sp. HM58-2 hydrazidase is a 631-amino-acid monomer that was 31% identical to indoleacetamide hydrolase isolated from Bradyrhizobium japonicum. Phylogenetic studies indicated that the Microbacterium sp. HM58-2 hydrazidase constitutes a novel hydrazidase group among amidase signature proteins that are distributed within proteobacteria, actinobacteria, and firmicutes. The hydrazidase stoichiometrically hydrolyzed the acylhydrazide residue of HBPH to the corresponding acid and hydrazine derivative. Steady-state kinetics showed that the enzyme hydrolyzes structurally related 4-hydrozybenzamide to hydroxybenzoic acid at a lower rate than HBPH, indicating that the hydrazidase prefers hydrazide to amide. The hydrazidase contains the catalytic Ser-Ser-Lys motif that is conserved among members of the amidase signature family; it shares a catalytic mechanism with amidases, according to mutagenesis findings, and another hydrazidase-specific mechanism must exist that compensates for the absence of the catalytic Ser residue. The finding that an environmental bacterium produces hydrazidase implies the existence of a novel bacterial mechanism of hydrazide degradation that impacts its ecological role.
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15
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Sánchez-Parra B, Frerigmann H, Alonso MMP, Loba VC, Jost R, Hentrich M, Pollmann S. Characterization of Four Bifunctional Plant IAM/PAM-Amidohydrolases Capable of Contributing to Auxin Biosynthesis. PLANTS 2014; 3:324-47. [PMID: 27135507 PMCID: PMC4844348 DOI: 10.3390/plants3030324] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 07/23/2014] [Accepted: 07/30/2014] [Indexed: 01/09/2023]
Abstract
Amidases [EC 3.5.1.4] capable of converting indole-3-acetamide (IAM) into the major plant growth hormone indole-3-acetic acid (IAA) are assumed to be involved in auxin de novo biosynthesis. With the emerging amount of genomics data, it was possible to identify over forty proteins with substantial homology to the already characterized amidases from Arabidopsis and tobacco. The observed high conservation of amidase-like proteins throughout the plant kingdom may suggest an important role of theses enzymes in plant development. Here, we report cloning and functional analysis of four, thus far, uncharacterized plant amidases from Oryza sativa, Sorghum bicolor, Medicago truncatula, and Populus trichocarpa. Intriguingly, we were able to demonstrate that the examined amidases are also capable of converting phenyl-2-acetamide (PAM) into phenyl-2-acetic acid (PAA), an auxin endogenous to several plant species including Arabidopsis. Furthermore, we compared the subcellular localization of the enzymes to that of Arabidopsis AMI1, providing further evidence for similar enzymatic functions. Our results point to the presence of a presumably conserved pathway of auxin biosynthesis via IAM, as amidases, both of monocot, and dicot origins, were analyzed.
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Affiliation(s)
- Beatriz Sánchez-Parra
- Center for Plant Biotechnology and Genomics (U.P.M.-I.N.I.A.), Technical University Madrid, Montegancedo Campus, Crta. M-40, km 38, 28223 Pozuelo de Alarcón (Madrid), Spain.
| | - Henning Frerigmann
- Department of Plant Physiology, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany.
| | - Marta-Marina Pérez Alonso
- Center for Plant Biotechnology and Genomics (U.P.M.-I.N.I.A.), Technical University Madrid, Montegancedo Campus, Crta. M-40, km 38, 28223 Pozuelo de Alarcón (Madrid), Spain.
| | - Víctor Carrasco Loba
- Center for Plant Biotechnology and Genomics (U.P.M.-I.N.I.A.), Technical University Madrid, Montegancedo Campus, Crta. M-40, km 38, 28223 Pozuelo de Alarcón (Madrid), Spain.
| | - Ricarda Jost
- School of Plant Biology, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
| | - Mathias Hentrich
- Department of Plant Physiology, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany.
| | - Stephan Pollmann
- Center for Plant Biotechnology and Genomics (U.P.M.-I.N.I.A.), Technical University Madrid, Montegancedo Campus, Crta. M-40, km 38, 28223 Pozuelo de Alarcón (Madrid), Spain.
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16
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Blancaflor EB, Kilaru A, Keereetaweep J, Khan BR, Faure L, Chapman KD. N-Acylethanolamines: lipid metabolites with functions in plant growth and development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 79:568-583. [PMID: 24397856 DOI: 10.1111/tpj.12427] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 12/18/2013] [Accepted: 12/23/2013] [Indexed: 06/03/2023]
Abstract
Twenty years ago, N-acylethanolamines (NAEs) were considered by many lipid chemists to be biological 'artifacts' of tissue damage, and were, at best, thought to be minor lipohilic constituents of various organisms. However, that changed dramatically in 1993, when anandamide, an NAE of arachidonic acid (N-arachidonylethanolamine), was shown to bind to the human cannabinoid receptor (CB1) and activate intracellular signal cascades in mammalian neurons. Now NAEs of various types have been identified in diverse multicellular organisms, in which they display profound biological effects. Although targets of NAEs are still being uncovered, and probably vary among eukaryotic species, there appears to be remarkable conservation of the machinery that metabolizes these bioactive fatty acid conjugates of ethanolamine. This review focuses on the metabolism and functions of NAEs in higher plants, with specific reference to the formation, hydrolysis and oxidation of these potent lipid mediators. The discussion centers mostly on early seedling growth and development, for which NAE metabolism has received the most attention, but also considers other areas of plant development in which NAE metabolism has been implicated. Where appropriate, we indicate cross-kingdom conservation in NAE metabolic pathways and metabolites, and suggest areas where opportunities for further investigation appear most pressing.
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Affiliation(s)
- Elison B Blancaflor
- Plant Biology Division, The Samuel Roberts Noble Foundation Inc., 2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
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Wu X, Huang R, Liu Z, Zhang G. Functional characterization of cis-elements conferring vascular vein expression of At4g34880 amidase family protein gene in Arabidopsis. PLoS One 2013; 8:e67562. [PMID: 23844031 PMCID: PMC3699661 DOI: 10.1371/journal.pone.0067562] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 05/20/2013] [Indexed: 12/18/2022] Open
Abstract
The expression of At4g34880 gene encoding amidase in Arabidopsis was characterized in this study. A promoter region of 1.5 kb on the upstream of the start codon of the gene (referred as AmidP) was fused with uidA (GUS) reporter gene, and transformed into Arabidopsis plant for determining its spatial expression. The results indicated that AmidP drived GUS expression in vascular system, predominately in leaves. Truncation analysis of AmidP demonstrated that VASCULAR VEIN ELEMENT (VVE) motif with a region of 176 bp sequence (−1500 to −1324) was necessary and sufficient to direct the vascular vein specific GUS expression in the transgenic plant. Tandem copy of VVE increased vascular system expression, and 5′- and 3′- deletions of VVE motif in combination with a truncated −65 CaMV 35S minimal promoter showed that 11bp cis-acting element, naming DOF2 domain, played an essential role for the vascular vein specific expression. Meanwhile, it was also observed that the other cis-acting elements among the VVE region are also associated with specificity or strength of GUS activities in vascular system.
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Affiliation(s)
- Xuelong Wu
- Department of Agronomy, Key Laboratory of Crop Germplasm Resource, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China
- Institute of Virology and Biotechnology, Key Laboratory of Plant Metabolic Engineering of Zhejiang Province, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China
| | - Ruizhi Huang
- Institute of Virology and Biotechnology, Key Laboratory of Plant Metabolic Engineering of Zhejiang Province, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China
| | - Zhihong Liu
- Institute of Virology and Biotechnology, Key Laboratory of Plant Metabolic Engineering of Zhejiang Province, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China
| | - Guoping Zhang
- Department of Agronomy, Key Laboratory of Crop Germplasm Resource, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China
- * E-mail:
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18
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Guo J, Pang Q, Wang L, Yu P, Li N, Yan X. Proteomic identification of MYC2-dependent jasmonate-regulated proteins in Arabidopsis thaliana. Proteome Sci 2012; 10:57. [PMID: 23009548 PMCID: PMC3598991 DOI: 10.1186/1477-5956-10-57] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 09/18/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND MYC2, a basic helix-loop-helix (bHLH) domain-containing transcription factor, participates in the jasmonate (JA) signaling pathway and is involved in the modulation of diverse JA functions. However, a comprehensive list of MYC2-dependent JA-responsive proteins has yet to be defined. RESULTS In this paper, we report the comparative proteomics of wild-type (WT) plants and jin1-9, a MYC2 mutant plant, in response to methyl jasmonate (MeJA) treatment. Proteins from mock/MeJA-treated jin1-9 and WT samples were extracted and separated by two-dimensional gel electrophoresis. Twenty-seven JA-mediated proteins demonstrated differential expression modulated by MYC2. We observed that MYC2 negatively regulates the accumulation of JA-dependent indolic glucosinolate-related proteins and exhibits opposite effects on the biosynthetic enzymes involved aliphatic glucosinolate pathways. In addition, proteins involved in the tricarboxylic acid cycle and a majority of the MeJA-inducible proteins that are involved in multiple protective systems against oxidative stress were reduced in jin1-9/myc2 sample compared to the WT sample. These results support a positive role for MYC2 in regulating JA-mediated carbohydrate metabolism and oxidative stress tolerance. CONCLUSIONS We have identified MYC2-dependent jasmonate-regulated proteins in Arabidopsis thaliana by performing two-dimensional gel electrophoresis and MALDI-TOF/TOF MS analysis. The observed pattern of protein expression suggests that MYC2 has opposite effects on the biosynthetic enzymes of indolic and aliphatic glucosinolate pathways and positively regulates JA-mediated carbohydrate metabolism and oxidative stress tolerance-related proteins. Furthermore, it is very interesting to note that MYC2 plays opposite roles in the modulation of a subset of JA-regulated photosynthetic proteins during short-term and long-term JA signaling. This study will enhance our understanding of the function of MYC2 in JA signaling in Arabidopsis thaliana.
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Affiliation(s)
- Jing Guo
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China.,Alkali Soil Natural Environmental Science Center; Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Northeast Forestry University, Harbin, 150040, China
| | - Qiuying Pang
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China.,Alkali Soil Natural Environmental Science Center; Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Northeast Forestry University, Harbin, 150040, China
| | - Lihua Wang
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China
| | - Ping Yu
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China
| | - Nan Li
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China
| | - Xiufeng Yan
- College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China
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Mano Y, Nemoto K. The pathway of auxin biosynthesis in plants. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:2853-72. [PMID: 22447967 DOI: 10.1093/jxb/ers091] [Citation(s) in RCA: 312] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The plant hormone auxin, which is predominantly represented by indole-3-acetic acid (IAA), is involved in the regulation of plant growth and development. Although IAA was the first plant hormone identified, the biosynthetic pathway at the genetic level has remained unclear. Two major pathways for IAA biosynthesis have been proposed: the tryptophan (Trp)-independent and Trp-dependent pathways. In Trp-dependent IAA biosynthesis, four pathways have been postulated in plants: (i) the indole-3-acetamide (IAM) pathway; (ii) the indole-3-pyruvic acid (IPA) pathway; (iii) the tryptamine (TAM) pathway; and (iv) the indole-3-acetaldoxime (IAOX) pathway. Although different plant species may have unique strategies and modifications to optimize their metabolic pathways, plants would be expected to share evolutionarily conserved core mechanisms for auxin biosynthesis because IAA is a fundamental substance in the plant life cycle. In this review, the genes now known to be involved in auxin biosynthesis are summarized and the major IAA biosynthetic pathway distributed widely in the plant kingdom is discussed on the basis of biochemical and molecular biological findings and bioinformatics studies. Based on evolutionarily conserved core mechanisms, it is thought that the pathway via IAM or IPA is the major route(s) to IAA in plants.
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Affiliation(s)
- Yoshihiro Mano
- Graduate School of Bioscience, Tokai University, 317 Nishino, Numazu, Shizuoka 410-0321, Japan.
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Teaster ND, Keereetaweep J, Kilaru A, Wang YS, Tang Y, Tran CNQ, Ayre BG, Chapman KD, Blancaflor EB. Overexpression of Fatty Acid Amide Hydrolase Induces Early Flowering in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2012; 3:32. [PMID: 22645580 PMCID: PMC3355813 DOI: 10.3389/fpls.2012.00032] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 02/01/2012] [Indexed: 05/19/2023]
Abstract
N-acylethanolamines (NAEs) are bioactive lipids derived from the hydrolysis of the membrane phospholipid N-acylphosphatidylethanolamine (NAPE). In animal systems this reaction is part of the "endocannabinoid" signaling pathway, which regulates a variety of physiological processes. The signaling function of NAE is terminated by fatty acid amide hydrolase (FAAH), which hydrolyzes NAE to ethanolamine and free fatty acid. Our previous work in Arabidopsis thaliana showed that overexpression of AtFAAH (At5g64440) lowered endogenous levels of NAEs in seeds, consistent with its role in NAE signal termination. Reduced NAE levels were accompanied by an accelerated growth phenotype, increased sensitivity to abscisic acid (ABA), enhanced susceptibility to bacterial pathogens, and early flowering. Here we investigated the nature of the early flowering phenotype of AtFAAH overexpression. AtFAAH overexpressors flowered several days earlier than wild type and AtFAAH knockouts under both non-inductive short day (SD) and inductive long day (LD) conditions. Microarray analysis revealed that the FLOWERING LOCUS T (FT) gene, which plays a major role in regulating flowering time, and one target MADS box transcription factor, SEPATALLA3 (SEP3), were elevated in AtFAAH overexpressors. Furthermore, AtFAAH overexpressors, with the early flowering phenotype had lower endogenous NAE levels in leaves compared to wild type prior to flowering. Exogenous application of NAE 12:0, which was reduced by up to 30% in AtFAAH overexpressors, delayed the onset of flowering in wild type plants. We conclude that the early flowering phenotype of AtFAAH overexpressors is, in part, explained by elevated FT gene expression resulting from the enhanced NAE hydrolase activity of AtFAAH, suggesting that NAE metabolism may participate in floral signaling pathways.
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Affiliation(s)
- Neal D. Teaster
- Plant Biology Division, The Samuel Roberts Noble FoundationArdmore, OK, USA
| | - Jantana Keereetaweep
- Department of Biological Sciences, Center for Plant Lipid Research, University of North TexasDenton, TX, USA
| | - Aruna Kilaru
- Department of Biological Sciences, East Tennessee State UniversityJohnson City, TN, USA
| | - Yuh-Shuh Wang
- Plant Signal Research Group, Institute of Technology, University of TartuTartu, Estonia
| | - Yuhong Tang
- Plant Biology Division, The Samuel Roberts Noble FoundationArdmore, OK, USA
| | - Christopher N.-Q. Tran
- Department of Biological Sciences, Center for Plant Lipid Research, University of North TexasDenton, TX, USA
| | - Brian G. Ayre
- Department of Biological Sciences, Center for Plant Lipid Research, University of North TexasDenton, TX, USA
| | - Kent D. Chapman
- Department of Biological Sciences, Center for Plant Lipid Research, University of North TexasDenton, TX, USA
| | - Elison B. Blancaflor
- Plant Biology Division, The Samuel Roberts Noble FoundationArdmore, OK, USA
- *Correspondence: Elison B. Blancaflor, Plant Biology Division, The Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK, USA. e-mail:
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Shen W, Chen H, Jia K, Ni J, Yan X, Li S. Cloning and characterization of a novel amidase from Paracoccus sp. M-1, showing aryl acylamidase and acyl transferase activities. Appl Microbiol Biotechnol 2011; 94:1007-18. [PMID: 22101784 DOI: 10.1007/s00253-011-3704-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2011] [Revised: 10/04/2011] [Accepted: 11/02/2011] [Indexed: 11/29/2022]
Abstract
A novel amidase gene, designated pamh, was cloned from Paracoccus sp. M-1. Site-directed mutagenesis and bioinformatic analysis showed that the PamH protein belonged to the amidase signature enzyme family. PamH was expressed in Escherichia coli, purified, and characterized. The molecular mass of PamH was determined to be 52 kDa with an isoelectric point of 5.13. PamH displayed its highest enzymatic activity at 45°C and at pH 8.0 and was stable within a pH range of 5.0-10.0. The PamH enzyme exhibited amidase activity, aryl acylamidase activity, and acyl transferase activity, allowing it to function across a very broad substrate spectrum. PamH was highly active on aromatic and short-chain aliphatic amides (benzamide and propionamide), moderately active on amino acid amides, and possessed weak urease activity. Of the anilides examined, only propanil was a good substrate for PamH. For propanil, the k (cat) and K (m) were 2.8 s(-1) and 158 μM, respectively, and the catalytic efficiency value (k (cat)/K (m)) was 0.018 μM(-1) s(-1). In addition, PamH was able to catalyze the acyl transfer reaction to hydroxylamine for both amide and anilide substrates, including acetamide, propanil, and 4-nitroacetanilide; the highest reaction rate was shown with isobutyramide. These characteristics make PamH an excellent candidate for environmental remediation and an important enzyme for the biosynthesis of novel amides.
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Affiliation(s)
- Weiliang Shen
- Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, 6 Tongwei Road, Nanjing, Jiangsu, People's Republic of China
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22
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Karpowicz SJ, Prochnik SE, Grossman AR, Merchant SS. The GreenCut2 resource, a phylogenomically derived inventory of proteins specific to the plant lineage. J Biol Chem 2011; 286:21427-39. [PMID: 21515685 PMCID: PMC3122202 DOI: 10.1074/jbc.m111.233734] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Revised: 04/11/2011] [Indexed: 11/06/2022] Open
Abstract
The plastid is a defining structure of photosynthetic eukaryotes and houses many plant-specific processes, including the light reactions, carbon fixation, pigment synthesis, and other primary metabolic processes. Identifying proteins associated with catalytic, structural, and regulatory functions that are unique to plastid-containing organisms is necessary to fully define the scope of plant biochemistry. Here, we performed phylogenomics on 20 genomes to compile a new inventory of 597 nucleus-encoded proteins conserved in plants and green algae but not in non-photosynthetic organisms. 286 of these proteins are of known function, whereas 311 are not characterized. This inventory was validated as applicable and relevant to diverse photosynthetic eukaryotes using an additional eight genomes from distantly related plants (including Micromonas, Selaginella, and soybean). Manual curation of the known proteins in the inventory established its importance to plastid biochemistry. To predict functions for the 52% of proteins of unknown function, we used sequence motifs, subcellular localization, co-expression analysis, and RNA abundance data. We demonstrate that 18% of the proteins in the inventory have functions outside the plastid and/or beyond green tissues. Although 32% of proteins in the inventory have homologs in all cyanobacteria, unexpectedly, 30% are eukaryote-specific. Finally, 8% of the proteins of unknown function share no similarity to any characterized protein and are plant lineage-specific. We present this annotated inventory of 597 proteins as a resource for functional analyses of plant-specific biochemistry.
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Affiliation(s)
| | - Simon E. Prochnik
- the United States Department of Energy Joint Genome Institute, Walnut Creek, California 94598, and
| | - Arthur R. Grossman
- the Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Sabeeha S. Merchant
- From the Department of Chemistry and Biochemistry and
- Institute for Genomics and Proteomics, UCLA, Los Angeles, California 90095
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23
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Hoffmann M, Lehmann T, Neu D, Hentrich M, Pollmann S. Expression of AMIDASE1 (AMI1) is suppressed during the first two days after germination. PLANT SIGNALING & BEHAVIOR 2010; 5:1642-1644. [PMID: 21150258 PMCID: PMC3115122 DOI: 10.4161/psb.5.12.13810] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 09/30/2010] [Indexed: 05/26/2023]
Abstract
The regulation of cellular auxin levels is a critical factor in determining plant growth and architecture, as indole-3-acetic acid (IAA) gradients along the plant axis and local IAA maxima are known to initiate numerous plant growth responses. The regulation of auxin homeostasis is mediated in part by transport, conjugation and deconjugation, as well as by de novo biosynthesis. However, the pathways of IAA biosynthesis are yet not entirely characterized at the molecular and biochemical level. It is suggested that several biosynthetic routes for the formation of IAA have evolved. One such pathway proceeds via the intermediate indole-3-acetamide (IAM), which is converted into IAA by the activity of specific IAM hydrolases, such as Arabidopsis AMIDASE1 (AMI1). In this article we present evidence to support the argument that AMI1-dependent IAA synthesis is likely not to be used during the first two days of seedling development.
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Affiliation(s)
- Maik Hoffmann
- Centro de Biotecnología y Genómica de Plantas (U.P.M.-I.N.I.A.); Campus de Montegancedo; Pozuelo de Alarcón; (Madrid), Spain
- Department of Plant Physiology; Ruhr-University Bochum; Bochum, Germany
| | - Thomas Lehmann
- Department of Plant Physiology; Ruhr-University Bochum; Bochum, Germany
| | - Daniel Neu
- Department of Plant Physiology; Ruhr-University Bochum; Bochum, Germany
| | - Mathias Hentrich
- Department of Plant Physiology; Ruhr-University Bochum; Bochum, Germany
| | - Stephan Pollmann
- Centro de Biotecnología y Genómica de Plantas (U.P.M.-I.N.I.A.); Campus de Montegancedo; Pozuelo de Alarcón; (Madrid), Spain
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Indole-3-acetamide-dependent auxin biosynthesis: a widely distributed way of indole-3-acetic acid production? Eur J Cell Biol 2010; 89:895-905. [PMID: 20701997 DOI: 10.1016/j.ejcb.2010.06.021] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
During the course of evolution plants have evolved a complex phytohormone-based network to regulate their growth and development. Herein auxins have a pivotal function, as they are involved in controlling virtually every aspect related to plant growth. Indole-3-acetic acid (IAA) is the major endogenous auxin of higher plants that is already known for more than 80 years. In spite of the long-standing interest in this topic, IAA biosynthesis is still only partially uncovered. Several pathways for the formation of IAA have been proposed over the past years, but none of these pathways are yet completely defined. The aim of this review is to summarize the current knowledge on the indole-3-acetamide (IAM)-dependent pathway of IAA production in plants and to discuss the properties of the involved proteins and genes, respectively. Their evolutionary relationship to known bacterial IAM hydrolases and other amidases from bacteria, algae, moss, and higher plants is discussed on the basis of phylogenetic analyses. Moreover, we report on the transcriptional regulation of the Arabidopsis AMI1 gene.
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Mano Y, Nemoto K, Suzuki M, Seki H, Fujii I, Muranaka T. The AMI1 gene family: indole-3-acetamide hydrolase functions in auxin biosynthesis in plants. JOURNAL OF EXPERIMENTAL BOTANY 2010; 61:25-32. [PMID: 19887500 DOI: 10.1093/jxb/erp292] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Novel genes that function in the conversion of indole-3-acetamide (IAM) into indole-3-acetic acid (IAA), which were previously thought to exist only in the bacterial genome, have been isolated from plants. The finding of the AtAMI1 gene in Arabidopsis thaliana and the NtAMI1 gene in Nicotiana tabacum, which encode indole-3-acetamide hydrolase, indicates the existence of a new pathway for auxin biosynthesis in plants. This review summarizes the characteristics of these genes involved in auxin biosynthesis and discusses the possibility of the AMI1 gene family being widely distributed in the plant kingdom. Its evolutionary relationship to bacterial indole-3-acetamide hydrolase, based on phylogenetic analyses, is also discussed.
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Affiliation(s)
- Yoshihiro Mano
- Graduate School of Bioscience, Tokai University, 317 Nishino, Numazu, Shizuoka 410-0321, Japan.
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26
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Yasuhira K, Shibata N, Mongami G, Uedo Y, Atsumi Y, Kawashima Y, Hibino A, Tanaka Y, Lee YH, Kato DI, Takeo M, Higuchi Y, Negoro S. X-ray crystallographic analysis of the 6-aminohexanoate cyclic dimer hydrolase: catalytic mechanism and evolution of an enzyme responsible for nylon-6 byproduct degradation. J Biol Chem 2009; 285:1239-48. [PMID: 19889645 DOI: 10.1074/jbc.m109.041285] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We performed x-ray crystallographic analyses of the 6-aminohexanoate cyclic dimer (Acd) hydrolase (NylA) from Arthrobacter sp., an enzyme responsible for the degradation of the nylon-6 industry byproduct. The fold adopted by the 472-amino acid polypeptide generated a compact mixed alpha/beta fold, typically found in the amidase signature superfamily; this fold was especially similar to the fold of glutamyl-tRNA(Gln) amidotransferase subunit A (z score, 49.4) and malonamidase E2 (z score, 44.8). Irrespective of the high degree of structural similarity to the typical amidase signature superfamily enzymes, the specific activity of NylA for glutamine, malonamide, and indoleacetamide was found to be lower than 0.5% of that for Acd. However, NylA possessed carboxylesterase activity nearly equivalent to the Acd hydrolytic activity. Structural analysis of the inactive complex between the activity-deficient S174A mutant of NylA and Acd, performed at 1.8 A resolution, suggested the following enzyme/substrate interactions: a Ser(174)-cis-Ser(150)-Lys(72) triad constitutes the catalytic center; the backbone N in Ala(171) and Ala(172) are involved in oxyanion stabilization; Cys(316)-S(gamma) forms a hydrogen bond with nitrogen (Acd-N(7)) at the uncleaved amide bond in two equivalent amide bonds of Acd. A single S174A, S150A, or K72A substitution in NylA by site-directed mutagenesis decreased the Acd hydrolytic and esterolytic activities to undetectable levels, indicating that Ser(174)-cis-Ser(150)-Lys(72) is essential for catalysis. In contrast, substitutions at position 316 specifically affected Acd hydrolytic activity, suggesting that Cys(316) is responsible for Acd binding. On the basis of the structure and functional analysis, we discussed the catalytic mechanisms and evolution of NylA in comparison with other Ser-reactive hydrolases.
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Affiliation(s)
- Kengo Yasuhira
- Department of Materials Science and Chemistry, Graduate School of Engineering, University of Hyogo, Hyogo 671-2201, Japan
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Kim SC, Kang L, Nagaraj S, Blancaflor EB, Mysore KS, Chapman KD. Mutations in Arabidopsis fatty acid amide hydrolase reveal that catalytic activity influences growth but not sensitivity to abscisic acid or pathogens. J Biol Chem 2009; 284:34065-74. [PMID: 19801664 DOI: 10.1074/jbc.m109.059022] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fatty acid amide hydrolase (FAAH) terminates the endocannabinoid signaling pathway that regulates numerous neurobehavioral processes in animals by hydrolyzing N-acylethanolamines (NAEs). Recently, an Arabidopsis FAAH homologue (AtFAAH) was identified, and several studies, especially those using AtFAAH overexpressing and knock-out lines, have suggested an in vivo role for FAAH in the catabolism of NAEs in plants. We previously reported that overexpression of AtFAAH in Arabidopsis resulted in accelerated seedling growth, and in seedlings that were insensitive to exogenous NAEs but hypersensitive to abscisic acid (ABA) and hypersusceptible to nonhost pathogens. Here we show that whereas the enhanced growth and NAE tolerance of the AtFAAH overexpressing seedlings depend on the catalytic activity of AtFAAH, hypersensitivity to ABA and hypersusceptibility to nonhost pathogens are independent of its enzymatic activity. Five amino acids known to be critical for rat FAAH activity are also conserved in AtFAAH (Lys-205, Ser-281, Ser-282, Ser-305, and Arg-307). Site-directed mutation of each of these conserved residues in AtFAAH abolished its hydrolytic activity when expressed in Escherichia coli, supporting a common catalytic mechanism in animal and plant FAAH enzymes. Overexpression of these inactive AtFAAH mutants in Arabidopsis showed no growth enhancement and no NAE tolerance, but still rendered the seedlings hypersensitive to ABA and hypersusceptible to nonhost pathogens to a degree similar to the overexpression of the native AtFAAH. Taken together, our findings suggest that the AtFAAH influences plant growth and interacts with ABA signaling and plant defense through distinctly different mechanisms.
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Affiliation(s)
- Sang-Chul Kim
- Department of Biological Sciences, Center for Plant Lipid Research, University of North Texas, Denton, Texas 76203, USA
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Nemoto K, Hara M, Suzuki M, Seki H, Muranaka T, Mano Y. The NtAMI1 gene functions in cell division of tobacco BY-2 cells in the presence of indole-3-acetamide. FEBS Lett 2009; 583:487-92. [PMID: 19121311 DOI: 10.1016/j.febslet.2008.12.049] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 12/19/2008] [Accepted: 12/23/2008] [Indexed: 10/21/2022]
Abstract
Tobacco (Nicotiana tabacum) Bright Yellow-2 (BY-2) cells can be grown in medium containing indole-3-acetamide (IAM). Based on this finding, the NtAMI1 gene, whose product is functionally equivalent to the AtAMI1 gene of Arabidopsis thaliana and the aux2 gene of Agrobacterium rhizogenes, was isolated from BY-2 cells. Overexpression of the NtAMI1 gene allowed BY-2 cells to proliferate at lower concentrations of IAM, whereas suppression of the NtAMI1 gene by RNA interference (RNAi) caused severe growth inhibition in the medium containing IAM. These results suggest that IAM is incorporated into plant cells and converted to the auxin, indole-3-acetic acid, by NtAMI1.
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Affiliation(s)
- Keiichirou Nemoto
- Graduate School of Bioscience, Tokai University, 317 Nishino, Numazu, Shizuoka 410-0321, Japan
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