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Cho YI, Armstrong CL, Sulpizio A, Acheampong KK, Banks KN, Bardhan O, Churchill SJ, Connolly-Sporing AE, Crawford CE, Cruz Parrilla PL, Curtis SM, De La Ossa LM, Epstein SC, Farrehi CJ, Hamrick GS, Hillegas WJ, Kang A, Laxton OC, Ling J, Matsumura SM, Merino VM, Mukhtar SH, Shah NJ, Londergan CH, Daly CA, Kokona B, Charkoudian LK. Engineered Chimeras Unveil Swappable Modular Features of Fatty Acid and Polyketide Synthase Acyl Carrier Proteins. Biochemistry 2022; 61:217-227. [PMID: 35073057 PMCID: PMC9357449 DOI: 10.1021/acs.biochem.1c00798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 12/23/2022]
Abstract
The strategic redesign of microbial biosynthetic pathways is a compelling route to access molecules of diverse structure and function in a potentially environmentally sustainable fashion. The promise of this approach hinges on an improved understanding of acyl carrier proteins (ACPs), which serve as central hubs in biosynthetic pathways. These small, flexible proteins mediate the transport of molecular building blocks and intermediates to enzymatic partners that extend and tailor the growing natural products. Past combinatorial biosynthesis efforts have failed due to incompatible ACP-enzyme pairings. Herein, we report the design of chimeric ACPs with features of the actinorhodin polyketide synthase ACP (ACT) and of the Escherichia coli fatty acid synthase (FAS) ACP (AcpP). We evaluate the ability of the chimeric ACPs to interact with the E. coli FAS ketosynthase FabF, which represents an interaction essential to building the carbon backbone of the synthase molecular output. Given that AcpP interacts with FabF but ACT does not, we sought to exchange modular features of ACT with AcpP to confer functionality with FabF. The interactions of chimeric ACPs with FabF were interrogated using sedimentation velocity experiments, surface plasmon resonance analyses, mechanism-based cross-linking assays, and molecular dynamics simulations. Results suggest that the residues guiding AcpP-FabF compatibility and ACT-FabF incompatibility may reside in the loop I, α-helix II region. These findings can inform the development of strategic secondary element swaps that expand the enzyme compatibility of ACPs across systems and therefore represent a critical step toward the strategic engineering of "un-natural" natural products.
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Affiliation(s)
- Yae In Cho
- Department of Chemistry, Haverford College, Haverford, PA 19041
| | | | - Ariana Sulpizio
- Department of Chemistry, Haverford College, Haverford, PA 19041
| | | | | | - Oishi Bardhan
- Department of Chemistry, Haverford College, Haverford, PA 19041
| | | | | | | | | | - Sarah M. Curtis
- Department of Chemistry, Haverford College, Haverford, PA 19041
| | | | | | | | | | | | - Austin Kang
- Department of Chemistry, Haverford College, Haverford, PA 19041
| | | | - Joie Ling
- Department of Chemistry, Haverford College, Haverford, PA 19041
| | | | | | | | - Neel J. Shah
- Department of Chemistry, Haverford College, Haverford, PA 19041
| | | | - Clyde A. Daly
- Department of Chemistry, Haverford College, Haverford, PA 19041
| | - Bashkim Kokona
- Department of Chemistry, Haverford College, Haverford, PA 19041
- Spark Therapeutics, Philadelphia PA 19041
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Whaley SG, Radka CD, Subramanian C, Frank MW, Rock CO. Malonyl-acyl carrier protein decarboxylase activity promotes fatty acid and cell envelope biosynthesis in Proteobacteria. J Biol Chem 2021; 297:101434. [PMID: 34801557 PMCID: PMC8666670 DOI: 10.1016/j.jbc.2021.101434] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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: 09/13/2021] [Revised: 11/02/2021] [Accepted: 11/09/2021] [Indexed: 11/20/2022] Open
Abstract
Bacterial fatty acid synthesis in Escherichia coli is initiated by the condensation of an acetyl-CoA with a malonyl-acyl carrier protein (ACP) by the β-ketoacyl-ACP synthase III enzyme, FabH. E. coli ΔfabH knockout strains are viable because of the yiiD gene that allows FabH-independent fatty acid synthesis initiation. However, the molecular function of the yiiD gene product is not known. Here, we show the yiiD gene product is a malonyl-ACP decarboxylase (MadA). MadA has two independently folded domains: an amino-terminal N-acetyl transferase (GNAT) domain (MadAN) and a carboxy-terminal hot dog dimerization domain (MadAC) that encodes the malonyl-ACP decarboxylase function. Members of the proteobacterial Mad protein family are either two domain MadA (GNAT-hot dog) or standalone MadB (hot dog) decarboxylases. Using structure-guided, site-directed mutagenesis of MadB from Shewanella oneidensis, we identified Asn45 on a conserved catalytic loop as critical for decarboxylase activity. We also found that MadA, MadAC, or MadB expression all restored normal cell size and growth rates to an E. coli ΔfabH strain, whereas the expression of MadAN did not. Finally, we verified that GlmU, a bifunctional glucosamine-1-phosphate N-acetyl transferase/N-acetyl-glucosamine-1-phosphate uridylyltransferase that synthesizes the key intermediate UDP-GlcNAc, is an ACP binding protein. Acetyl-ACP is the preferred glucosamine-1-phosphate N-acetyl transferase/N-acetyl-glucosamine-1-phosphate uridylyltransferase substrate, in addition to being the substrate for the elongation-condensing enzymes FabB and FabF. Thus, we conclude that the Mad family of malonyl-ACP decarboxylases supplies acetyl-ACP to support the initiation of fatty acid, lipopolysaccharide, peptidoglycan, and enterobacterial common antigen biosynthesis in Proteobacteria.
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Affiliation(s)
- Sarah G Whaley
- Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Christopher D Radka
- Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Chitra Subramanian
- Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Matthew W Frank
- Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Charles O Rock
- Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, Tennessee, USA.
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3
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Gibbs NM, Su S, Lopez‐Nieves S, Mann S, Alban C, Maeda HA, Masson PH. Cadaverine regulates biotin synthesis to modulate primary root growth in Arabidopsis. Plant J 2021; 107:1283-1298. [PMID: 34250670 PMCID: PMC8518694 DOI: 10.1111/tpj.15417] [Citation(s) in RCA: 2] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/23/2021] [Accepted: 07/06/2021] [Indexed: 06/13/2023]
Abstract
Cadaverine, a polyamine, has been linked to modification of root growth architecture and response to environmental stresses in plants. However, the molecular mechanisms that govern the regulation of root growth by cadaverine are largely unexplored. Here we conducted a forward genetic screen and isolated a mutation, cadaverine hypersensitive 3 (cdh3), which resulted in increased root-growth sensitivity to cadaverine, but not other polyamines. This mutation affects the BIO3-BIO1 biotin biosynthesis gene. Exogenous supply of biotin and a pathway intermediate downstream of BIO1, 7,8-diaminopelargonic acid, suppressed this cadaverine sensitivity phenotype. An in vitro enzyme assay showed cadaverine inhibits the BIO3-BIO1 activity. Furthermore, cadaverine-treated seedlings displayed reduced biotinylation of Biotin Carboxyl Carrier Protein 1 of the acetyl-coenzyme A carboxylase complex involved in de novo fatty acid biosynthesis, resulting in decreased accumulation of triacylglycerides. Taken together, these results revealed an unexpected role of cadaverine in the regulation of biotin biosynthesis, which leads to modulation of primary root growth of plants.
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Affiliation(s)
- Nicole M. Gibbs
- Laboratory of GeneticsUniversity of Wisconsin‐MadisonMadisonWI53706USA
- Present address:
Plant Molecular and Cellular Biology LaboratorySalk Institute for Biological StudiesLa JollaCA92037USA
| | - Shih‐Heng Su
- Laboratory of GeneticsUniversity of Wisconsin‐MadisonMadisonWI53706USA
| | | | - Stéphane Mann
- Muséum National d'Histoire NaturelleUMR 7245CNRSMNHNMolécules de Communication et Adaptation des Micro‐organismesCP 5457 Rue CuvierParis75005France
| | - Claude Alban
- Université Grenoble AlpesINRAECEACNRSIRIGLPCVGrenoble38000France
| | - Hiroshi A. Maeda
- Department of BotanyUniversity of Wisconsin‐MadisonMadisonWI53706USA
| | - Patrick H. Masson
- Laboratory of GeneticsUniversity of Wisconsin‐MadisonMadisonWI53706USA
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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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Tomčala A, Michálek J, Schneedorferová I, Füssy Z, Gruber A, Vancová M, Oborník M. Fatty Acid Biosynthesis in Chromerids. Biomolecules 2020; 10:E1102. [PMID: 32722284 PMCID: PMC7464705 DOI: 10.3390/biom10081102] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 07/12/2020] [Accepted: 07/15/2020] [Indexed: 12/12/2022] Open
Abstract
Fatty acids are essential components of biological membranes, important for the maintenance of cellular structures, especially in organisms with complex life cycles like protozoan parasites. Apicomplexans are obligate parasites responsible for various deadly diseases of humans and livestock. We analyzed the fatty acids produced by the closest phototrophic relatives of parasitic apicomplexans, the chromerids Chromera velia and Vitrella brassicaformis, and investigated the genes coding for enzymes involved in fatty acids biosynthesis in chromerids, in comparison to their parasitic relatives. Based on evidence from genomic and metabolomic data, we propose a model of fatty acid synthesis in chromerids: the plastid-localized FAS-II pathway is responsible for the de novo synthesis of fatty acids reaching the maximum length of 18 carbon units. Short saturated fatty acids (C14:0-C18:0) originate from the plastid are then elongated and desaturated in the cytosol and the endoplasmic reticulum. We identified giant FAS I-like multi-modular enzymes in both chromerids, which seem to be involved in polyketide synthesis and fatty acid elongation. This full-scale description of the biosynthesis of fatty acids and their derivatives provides important insights into the reductive evolutionary transition of a phototropic algal ancestor to obligate parasites.
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Affiliation(s)
- Aleš Tomčala
- Biology Centre CAS, Institute of Parasitology, Branišovská 31, 370 05 České Budějovice, Czech Republic; (A.T.); (J.M.); (I.S.); (Z.F.); (A.G.); (M.V.)
- Faculty of Fisheries and Protection of Waters, CENAKVA, Institute of Aquaculture and Protection of Waters, University of South Bohemia, Husova 458/102, 370 05 České Budějovice, Czech Republic
| | - Jan Michálek
- Biology Centre CAS, Institute of Parasitology, Branišovská 31, 370 05 České Budějovice, Czech Republic; (A.T.); (J.M.); (I.S.); (Z.F.); (A.G.); (M.V.)
- Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Ivana Schneedorferová
- Biology Centre CAS, Institute of Parasitology, Branišovská 31, 370 05 České Budějovice, Czech Republic; (A.T.); (J.M.); (I.S.); (Z.F.); (A.G.); (M.V.)
- Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Zoltán Füssy
- Biology Centre CAS, Institute of Parasitology, Branišovská 31, 370 05 České Budějovice, Czech Republic; (A.T.); (J.M.); (I.S.); (Z.F.); (A.G.); (M.V.)
| | - Ansgar Gruber
- Biology Centre CAS, Institute of Parasitology, Branišovská 31, 370 05 České Budějovice, Czech Republic; (A.T.); (J.M.); (I.S.); (Z.F.); (A.G.); (M.V.)
| | - Marie Vancová
- Biology Centre CAS, Institute of Parasitology, Branišovská 31, 370 05 České Budějovice, Czech Republic; (A.T.); (J.M.); (I.S.); (Z.F.); (A.G.); (M.V.)
| | - Miroslav Oborník
- Biology Centre CAS, Institute of Parasitology, Branišovská 31, 370 05 České Budějovice, Czech Republic; (A.T.); (J.M.); (I.S.); (Z.F.); (A.G.); (M.V.)
- Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
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Shivaiah KK, Ding G, Upton B, Nikolau BJ. Non-Catalytic Subunits Facilitate Quaternary Organization of Plastidic Acetyl-CoA Carboxylase. Plant Physiol 2020; 182:756-775. [PMID: 31792149 PMCID: PMC6997691 DOI: 10.1104/pp.19.01246] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 11/19/2019] [Indexed: 05/18/2023]
Abstract
Arabidopsis (Arabidopsis thaliana), like most dicotyledonous plants, expresses a multicomponent, heteromeric acetyl-CoA carboxylase (htACCase), which catalyzes the generation of the malonyl-CoA precursor of de novo fatty acid biosynthesis. This enzyme consists of four catalytic subunits: biotin carboxylase (BC), carboxyltransferase (CT)-α, CT-β, and biotin carboxyl carrier protein (BCCP1 or BCCP2). By coexpressing combinations of components in a bacterial expression system, we demonstrate noncatalytic BADCs facilitate the assembly and activation of BCCP-BADC-BC subcomplexes catalyzing the bicarbonate-dependent hydrolysis of ATP, which is the first half-reaction catalyzed by the htACCase enzyme. Although BADC proteins do not directly impact formation of the CT-αβ subcomplex, the BADC-facilitated BCCP-BADC-BC subcomplex can more readily interact with the CT-αβ subcomplex to facilitate the generation of malonyl-CoA. The Arabidopsis genome encodes three BADC isoforms (BADC1, BADC2, and BADC3), and BADC2 and BADC3 (rather than BADC1), in combination with BCCP1, best support this quaternary-structural organization and catalytic activation of the htACCase enzyme. Physiological genetic studies validate these attributes as Arabidopsis double mutants singularly expressing BADC2, BADC3, or BADC1 present increasingly greater deleterious impacts on morphological and biochemical phenotypes. Specifically, plants expressing only BADC2 develop normally, plants only expressing BADC3 suffer a stunted root-growth phenotype, and plants expressing only BADC1 are embryo-lethal. The latter phenotype may also be associated with the distinct suborganelle localization of BADC1 in plastids as compared to the localization of the other two BADC homologs. These finding can inspire novel strategies to improve the biological sources of fats and oils for dietary and industrial applications.
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Affiliation(s)
- Kiran-Kumar Shivaiah
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011
- Center for Biorenewable Chemicals, Iowa State University, Ames, Iowa 50011
- Center for Metabolic Biology, Iowa State University, Ames, Iowa 50011
| | - Geng Ding
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011
- Center for Biorenewable Chemicals, Iowa State University, Ames, Iowa 50011
- Center for Metabolic Biology, Iowa State University, Ames, Iowa 50011
| | - Bryon Upton
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011
- Center for Biorenewable Chemicals, Iowa State University, Ames, Iowa 50011
- Center for Metabolic Biology, Iowa State University, Ames, Iowa 50011
| | - Basil J Nikolau
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011
- Center for Biorenewable Chemicals, Iowa State University, Ames, Iowa 50011
- Center for Metabolic Biology, Iowa State University, Ames, Iowa 50011
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Abstract
Carrier proteins are four-helix bundles that covalently hold metabolites and secondary metabolites, such as fatty acids, polyketides and non-ribosomal peptides. These proteins mediate the production of many pharmaceutically important compounds including antibiotics and anticancer agents. Acyl carrier proteins (ACPs) can be found as part of a multi-domain polypeptide (Type I ACPs), or as part of a multiprotein complex (Type II). Here, the main focus is on ACP2 and ACP3, domains from the type I trans-AT polyketide synthase MmpA, which is a core component of the biosynthetic pathway of the antibiotic mupirocin. During molecular dynamics simulations of their apo, holo and acyl forms ACP2 and ACP3 both form a substrate-binding surface-groove. The substrates bound to this surface-groove have polar groups on their acyl chain exposed and forming hydrogen bonds with the solvent. Bulky hydrophobic residues in the GXDS motif common to all ACPs, and similar residues on helix III, appear to prohibit the formation of a deep tunnel in type I ACPs and type II ACPs from polyketide synthases. In contrast, the equivalent positions in ACPs from type II fatty acid synthases, which do form a deep solvent-excluded substrate-binding tunnel, have the small residue alanine. During simulation, ACP3 with mutations I61A L36A W44L forms a deep tunnel that can fully bury a saturated substrate in the core of the ACP, in contrast to the surface groove of the wild type ACP3. Similarly, in the ACP from E. coli fatty acid synthase, a type II ACP, mutations can change ligand binding from being inside a deep tunnel to being in a surface groove, thus demonstrating how changing a few residues can modify the possibilities for ligand binding.
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Affiliation(s)
- Rohit Farmer
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- Department of Computational Biology and Bioinformatics, Jacob Institute of Biotechnology and Bioengineering, Sam Higginbottom University of Agriculture, Technology and Sciences, Allahabad, India
| | - Christopher Morton Thomas
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- The Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Peter James Winn
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- The Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- Centre for Computational Biology, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- * E-mail:
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Park J, Lee Y, Cheon D, Kim Y. Structure and dynamics of human and bacterial acyl carrier proteins and their interactions with fatty acid synthesis proteins. Biochem Biophys Res Commun 2019; 516:1183-1189. [PMID: 31296387 DOI: 10.1016/j.bbrc.2019.07.018] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 07/05/2019] [Indexed: 11/17/2022]
Abstract
Acyl carrier protein (ACP) is highly conserved across taxa and plays key roles in the fatty acid synthesis system by mediating acyl group delivery and shuttling. Here, we compared the structural and dynamic features of human type Ι ACP (hACP) and Escherichia coli type II ACP (EcACP). Analysis of chemical shift perturbations upon octanoyl group attachment showed perturbations in hACP only near acyl-group attachment sites, whereas EcACP showed the perturbation at residues in the hydrophobic cavity. This difference confirmed that hACP does not sequester the acyl chain in the hydrophobic cavity, which is blocked by hydrophobic triad residues (L34, L39, and V64). Moreover, hACP showed more flexible backbone dynamics than EcACP, especially in the front of α1α2 loop. We further investigated the interactions of hACP with Streptomyces coelicolor ACP synthase (ScAcpS), which is used to convert apo mammalian ACP to the holo form. Similar to protein-protein interface (PPI) found in hACP-hAcpS crystal structure, docking simulation and binding affinity measurements showed that the hydrophobic residues in universal recognition helix II of hACP contribute mainly to ScAcpS binding with binding affinity of 9.2 ± 9.1 × 104 M. In contrast, interaction found in EcACP-EcAcpS crystal structure is dominated by electrostatic interactions. These results suggest that ScAcpS has relatively relaxed substrate specificity and a similar charge distribution to hAcpS. These fundamental differences of the charge distribution in hAcpS, ScAcpS and EcAcpS largely affect the interaction with hACP. These findings can provide a useful resource for development of novel antibiotics inhibiting PPI in bacterial FAS proteins with specificity.
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Affiliation(s)
- Jungwoo Park
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, South Korea
| | - Yeongjoon Lee
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, South Korea
| | - Dasom Cheon
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, South Korea
| | - Yangmee Kim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, South Korea.
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Lee AR, Kwon M, Kang MK, Kim J, Kim SU, Ro DK. Increased sesqui- and triterpene production by co-expression of HMG-CoA reductase and biotin carboxyl carrier protein in tobacco (Nicotiana benthamiana). Metab Eng 2019; 52:20-28. [PMID: 30389612 DOI: 10.1016/j.ymben.2018.10.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [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: 05/12/2018] [Revised: 08/29/2018] [Accepted: 10/27/2018] [Indexed: 01/16/2023]
Abstract
Terpenoids are the most diverse natural products with many industrial applications and are all synthesized from simple precursors, isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP). In plants, IPP is synthesized by two distinct metabolic pathways - cytosolic mevalonate (MVA) pathway for C15 sesquiterpene and C30 triterpene, and plastidic methylerythritol phosphate (MEP) pathway for C10 monoterpene and C20 diterpene. A number of studies have altered the metabolic gene expressions in either the MVA or MEP pathway to increase terpene production; however, it remains unknown if the alteration of the acetyl-CoA pool in plastid fatty acid biosynthesis can influence terpenoid flux. Here, we focused on the fact that acetyl-CoA is the precursor for both fatty acid biosynthesis in plastid and terpene biosynthesis in cytosol, and the metabolic impact of increased plastidic acetyl-CoA level on the cytosolic terpene biosynthesis was investigated. In tobacco leaf infiltration studies, the acetyl-CoA carboxylase complex (the enzyme supplying malonyl-CoA in plastid) was partially inhibited by overexpressing the inactive form of biotin carboxyl carrier protein (BCCP) by a negative dominant effect. Overexpression of BCCP showed 1.4-2.4-fold increase of sesquiterpenes in cytosol; however, surprisingly overexpression of BCCP linked to truncated HMG-CoA reductase (tHMGR) by a cleavable peptide 2A showed 20-40-fold increases of C15 sesquiterpenes (α-bisabolol, amorphadiene, and valerenadiene) and a 6-fold increase of C30 β-amyrin. α-Bisabolol and β-amyrin production reached 28.8 mg g-1 and 9.8 mg g-1 dry weight, respectively. Detailed analyses showed that a large increase in flux was achieved by the additive effect of BCCP- and tHMGR-overexpression, and an enhanced tHMGR activity by 2A peptide tag. Kinetic analyses showed that tHMGR-2A has a three-fold higher kcat value than tHMGR. The tHMGR-2A-BCCP1 co-expression strategy in this work provides a new insight into metabolic cross-talks and can be a generally applicable approach to over-produce sesqui- and tri-terpene in plants.
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Affiliation(s)
- Ah-Reum Lee
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Moonhyuk Kwon
- Division of Applied Life Science (BK21 Plus), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, 52828, Republic of Korea; Department of Biological Sciences, University of Calgary, Calgary, AB, T2N1N4, Canada
| | - Min-Kyoung Kang
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jeonghan Kim
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Soo-Un Kim
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea; College of Horticulture and Gardening, Yangtze University, Jingzhou 434023, Hubei, China.
| | - Dae-Kyun Ro
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N1N4, Canada.
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Abstract
Covering: up to April 5, 2018 Metabolites from type II fatty acid synthase (FAS) and polyketide synthase (PKS) pathways differ broadly in their identities and functional roles. The former are considered primary metabolites that are linear hydrocarbon acids, while the latter are complex aromatic or polyunsaturated secondary metabolites. Though the study of bacterial FAS has benefitted from decades of biochemical and structural investigations, type II PKSs have remained less understood. Here we review the recent approaches to understanding the protein-protein and protein-substrate interactions in these pathways, with an emphasis on recent chemical biology and structural applications. New approaches to the study of FAS have highlighted the critical role of the acyl carrier protein (ACP) with regard to how it stabilizes intermediates through sequestration and selectively delivers cargo to successive enzymes within these iterative pathways, utilizing protein-protein interactions to guide and organize enzymatic timing and specificity. Recent tools that have shown promise in FAS elucidation should find new approaches to studying type II PKS systems in the coming years.
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Affiliation(s)
- Aochiu Chen
- Department of Chemistry and Biochemistry, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA.
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11
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Lee WC, Park J, Balasubramanian PK, Kim Y. Elucidation of the crystal structure of FabD from the multidrug-resistant bacterium Acinetobacter baumannii. Biochem Biophys Res Commun 2018; 505:208-214. [PMID: 30243724 DOI: 10.1016/j.bbrc.2018.09.079] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [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: 08/23/2018] [Revised: 09/10/2018] [Accepted: 09/12/2018] [Indexed: 11/29/2022]
Abstract
Bacterial fatty acid synthesis (FAS) has been extensively studied as a potential target of antimicrobials. In FAS, FabD mediates transacylation of the malonyl group from malonyl-CoA to acyl-carrier protein (ACP). The mounting threat of nosocomial infection by multidrug-resistant Acinetobacter baumannii warrants a deeper understanding of its essential cellular mechanisms, which could lead to effective control of this highly competent pathogen. The molecular mechanisms involved in A. baumannii FAS are poorly understood, and recent research has suggested that Pseudomonas aeruginosa, a closely related nosocomial pathogen of A. baumannii, utilizes FAS to produce virulence factors. In this study, we solved the crystal structure of A. baumannii FabD (AbFabD) to provide a platform for the development of new antibacterial agents. Analysis of the structure of AbFabD confirmed the presence of highly conserved active site residues among bacterial homologs. Binding constants between AbFabD variants and A. baumannii ACP (AbACP) revealed critical conserved residues Lys195 and Lys200 involved in AbACP binding. Computational docking of a potential inhibitor, trifluoperazine, revealed a unique inhibitor-binding pocket near the substrate-binding site. The structural study presented herein will be useful for the structure-based design of potent AbFabD inhibitors.
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Affiliation(s)
- Woo Cheol Lee
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, Republic of Korea
| | - Jungwoo Park
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, Republic of Korea
| | | | - Yangmee Kim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, Republic of Korea.
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12
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Rullán‐Lind C, Pietri RB, Vázquez‐Cintrón M, Baerga‐Ortiz A. Fused dimerization increases expression, solubility, and activity of bacterial dehydratase enzymes. Protein Sci 2018; 27:969-975. [PMID: 29520922 PMCID: PMC5916124 DOI: 10.1002/pro.3404] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [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: 12/30/2017] [Revised: 03/05/2018] [Accepted: 03/07/2018] [Indexed: 01/12/2023]
Abstract
FabA and FabZ are the two dehydratase enzymes in Escherichia coli that catalyze the dehydration of acyl intermediates in the biosynthesis of fatty acids. Both enzymes form obligate dimers in which the active site contains key amino acids from both subunits. While FabA is a soluble protein that has been relatively straightforward to express and to purify from cultured E. coli, FabZ has shown to be mostly insoluble and only partially active. In an effort to increase the solubility and activity of both dehydratases, we made constructs consisting of two identical subunits of FabA or FabZ fused with a naturally occurring peptide linker, so as to force their dimerization. The fused dimer of FabZ (FabZ-FabZ) was expressed as a soluble enzyme with an ninefold higher activity in vitro than the unfused FabZ. This construct exemplifies a strategy for the improvement of enzymes from the fatty acid biosynthesis pathways, many of which function as dimers, catalyzing critical steps for the production of fatty acids.
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Affiliation(s)
- Carlos Rullán‐Lind
- Department of BiochemistryUniversity of Puerto Rico, Medical Sciences CampusSan Juan00936‐5067Puerto Rico
- Molecular Sciences Research Center, University of Puerto RicoSan JuanPuerto Rico
| | - Ruth B. Pietri
- Department of ChemistryUniversity of Puerto Rico, Cayey CampusCayeyPuerto Rico
| | - Melvin Vázquez‐Cintrón
- Department of BiochemistryUniversity of Puerto Rico, Medical Sciences CampusSan Juan00936‐5067Puerto Rico
- Molecular Sciences Research Center, University of Puerto RicoSan JuanPuerto Rico
| | - Abel Baerga‐Ortiz
- Department of BiochemistryUniversity of Puerto Rico, Medical Sciences CampusSan Juan00936‐5067Puerto Rico
- Molecular Sciences Research Center, University of Puerto RicoSan JuanPuerto Rico
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13
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Shuib S, Ibrahim I, Mackeen MM, Ratledge C, Hamid AA. First evidence for a multienzyme complex of lipid biosynthesis pathway enzymes in Cunninghamella bainieri. Sci Rep 2018; 8:3077. [PMID: 29449592 PMCID: PMC5814418 DOI: 10.1038/s41598-018-21452-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [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: 11/16/2017] [Accepted: 01/31/2018] [Indexed: 11/17/2022] Open
Abstract
Malic enzyme (ME) plays a vital role in determining the extent of lipid accumulation in oleaginous fungi being the major provider of NADPH for the activity of fatty acid synthase (FAS). We report here the first direct evidence of the existence of a lipogenic multienzyme complex (the lipid metabolon) involving ME, FAS, ATP: citrate lyase (ACL), acetyl-CoA carboxylase (ACC), pyruvate carboxylase (PC) and malate dehydrogenase (MDH) in Cunninghamella bainieri 2A1. Cell-free extracts prepared from cells taken in both growth and lipid accumulation phases were prepared by protoplasting and subjected to Blue Native (BN)-PAGE coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). A high molecular mass complex (approx. 3.2 MDa) consisting of the above enzymes was detected during lipid accumulation phase indicating positive evidence of multienzyme complex formation. The complex was not detected in cells during the balanced phase of growth or when lipid accumulation ceased, suggesting that it was transiently formed only during lipogenesis.
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Affiliation(s)
- Shuwahida Shuib
- School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia
| | - Izyanti Ibrahim
- School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia
| | - Mukram Mohamed Mackeen
- School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia
| | - Colin Ratledge
- Department of Biological Sciences, University of Hull, Kingston upon Hull, HU6 7RX, United Kingdom
| | - Aidil Abdul Hamid
- School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia.
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14
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Guan X, Okazaki Y, Lithio A, Li L, Zhao X, Jin H, Nettleton D, Saito K, Nikolau BJ. Discovery and Characterization of the 3-Hydroxyacyl-ACP Dehydratase Component of the Plant Mitochondrial Fatty Acid Synthase System. Plant Physiol 2017; 173:2010-2028. [PMID: 28202596 PMCID: PMC5373057 DOI: 10.1104/pp.16.01732] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 02/08/2017] [Indexed: 05/06/2023]
Abstract
We report the characterization of the Arabidopsis (Arabidopsis thaliana) 3-hydroxyacyl-acyl carrier protein dehydratase (mtHD) component of the mitochondrial fatty acid synthase (mtFAS) system, encoded by AT5G60335. The mitochondrial localization and catalytic capability of mtHD were demonstrated with a green fluorescent protein transgenesis experiment and by in vivo complementation and in vitro enzymatic assays. RNA interference (RNAi) knockdown lines with reduced mtHD expression exhibit traits typically associated with mtFAS mutants, namely a miniaturized morphological appearance, reduced lipoylation of lipoylated proteins, and altered metabolomes consistent with the reduced catalytic activity of lipoylated enzymes. These alterations are reversed when mthd-rnai mutant plants are grown in a 1% CO2 atmosphere, indicating the link between mtFAS and photorespiratory deficiency due to the reduced lipoylation of glycine decarboxylase. In vivo biochemical feeding experiments illustrate that sucrose and glycolate are the metabolic modulators that mediate the alterations in morphology and lipid accumulation. In addition, both mthd-rnai and mtkas mutants exhibit reduced accumulation of 3-hydroxytetradecanoic acid (i.e. a hallmark of lipid A-like molecules) and abnormal chloroplastic starch granules; these changes are not reversible by the 1% CO2 atmosphere, demonstrating two novel mtFAS functions that are independent of photorespiration. Finally, RNA sequencing analysis revealed that mthd-rnai and mtkas mutants are nearly equivalent to each other in altering the transcriptome, and these analyses further identified genes whose expression is affected by a functional mtFAS system but independent of photorespiratory deficiency. These data demonstrate the nonredundant nature of the mtFAS system, which contributes unique lipid components needed to support plant cell structure and metabolism.
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MESH Headings
- Amino Acid Sequence
- Arabidopsis/enzymology
- Arabidopsis/genetics
- Arabidopsis Proteins/genetics
- Arabidopsis Proteins/metabolism
- Blotting, Western
- Carbon Dioxide/metabolism
- Fatty Acid Synthase, Type II/genetics
- Fatty Acid Synthase, Type II/metabolism
- Fatty Acid Synthases/genetics
- Fatty Acid Synthases/metabolism
- Gene Expression Regulation, Plant
- Glycolates/metabolism
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- Hydro-Lyases/genetics
- Hydro-Lyases/metabolism
- Metabolomics/methods
- Microscopy, Confocal
- Microscopy, Electron, Transmission
- Mitochondria/enzymology
- Mitochondria/ultrastructure
- Mutation
- Myristic Acids/metabolism
- Plants, Genetically Modified
- RNA Interference
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Analysis, RNA/methods
- Sequence Homology, Amino Acid
- Sucrose/metabolism
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Affiliation(s)
- Xin Guan
- Department of Biochemistry, Biophysics, and Molecular Biology (X.G., H.J., B.J.N.), National Science Foundation Engineering Research Center for Biorenewable Chemicals (X.G., B.J.N.), Department of Statistics (A.L., D.N.), Department of Genetics, Development, and Cellular Biology (L.L.), Laurence H. Baker Center for Bioinformatics and Biological Statistics (X.Z.), and Center for Metabolic Biology (B.J.N.), Iowa State University, Ames, Iowa 50011
- Metabolomics Research Group, RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.O., K.S.); and
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Yozo Okazaki
- Department of Biochemistry, Biophysics, and Molecular Biology (X.G., H.J., B.J.N.), National Science Foundation Engineering Research Center for Biorenewable Chemicals (X.G., B.J.N.), Department of Statistics (A.L., D.N.), Department of Genetics, Development, and Cellular Biology (L.L.), Laurence H. Baker Center for Bioinformatics and Biological Statistics (X.Z.), and Center for Metabolic Biology (B.J.N.), Iowa State University, Ames, Iowa 50011
- Metabolomics Research Group, RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.O., K.S.); and
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Andrew Lithio
- Department of Biochemistry, Biophysics, and Molecular Biology (X.G., H.J., B.J.N.), National Science Foundation Engineering Research Center for Biorenewable Chemicals (X.G., B.J.N.), Department of Statistics (A.L., D.N.), Department of Genetics, Development, and Cellular Biology (L.L.), Laurence H. Baker Center for Bioinformatics and Biological Statistics (X.Z.), and Center for Metabolic Biology (B.J.N.), Iowa State University, Ames, Iowa 50011
- Metabolomics Research Group, RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.O., K.S.); and
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Ling Li
- Department of Biochemistry, Biophysics, and Molecular Biology (X.G., H.J., B.J.N.), National Science Foundation Engineering Research Center for Biorenewable Chemicals (X.G., B.J.N.), Department of Statistics (A.L., D.N.), Department of Genetics, Development, and Cellular Biology (L.L.), Laurence H. Baker Center for Bioinformatics and Biological Statistics (X.Z.), and Center for Metabolic Biology (B.J.N.), Iowa State University, Ames, Iowa 50011
- Metabolomics Research Group, RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.O., K.S.); and
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Xuefeng Zhao
- Department of Biochemistry, Biophysics, and Molecular Biology (X.G., H.J., B.J.N.), National Science Foundation Engineering Research Center for Biorenewable Chemicals (X.G., B.J.N.), Department of Statistics (A.L., D.N.), Department of Genetics, Development, and Cellular Biology (L.L.), Laurence H. Baker Center for Bioinformatics and Biological Statistics (X.Z.), and Center for Metabolic Biology (B.J.N.), Iowa State University, Ames, Iowa 50011
- Metabolomics Research Group, RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.O., K.S.); and
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Huanan Jin
- Department of Biochemistry, Biophysics, and Molecular Biology (X.G., H.J., B.J.N.), National Science Foundation Engineering Research Center for Biorenewable Chemicals (X.G., B.J.N.), Department of Statistics (A.L., D.N.), Department of Genetics, Development, and Cellular Biology (L.L.), Laurence H. Baker Center for Bioinformatics and Biological Statistics (X.Z.), and Center for Metabolic Biology (B.J.N.), Iowa State University, Ames, Iowa 50011
- Metabolomics Research Group, RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.O., K.S.); and
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Dan Nettleton
- Department of Biochemistry, Biophysics, and Molecular Biology (X.G., H.J., B.J.N.), National Science Foundation Engineering Research Center for Biorenewable Chemicals (X.G., B.J.N.), Department of Statistics (A.L., D.N.), Department of Genetics, Development, and Cellular Biology (L.L.), Laurence H. Baker Center for Bioinformatics and Biological Statistics (X.Z.), and Center for Metabolic Biology (B.J.N.), Iowa State University, Ames, Iowa 50011
- Metabolomics Research Group, RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.O., K.S.); and
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Kazuki Saito
- Department of Biochemistry, Biophysics, and Molecular Biology (X.G., H.J., B.J.N.), National Science Foundation Engineering Research Center for Biorenewable Chemicals (X.G., B.J.N.), Department of Statistics (A.L., D.N.), Department of Genetics, Development, and Cellular Biology (L.L.), Laurence H. Baker Center for Bioinformatics and Biological Statistics (X.Z.), and Center for Metabolic Biology (B.J.N.), Iowa State University, Ames, Iowa 50011
- Metabolomics Research Group, RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.O., K.S.); and
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Basil J Nikolau
- Department of Biochemistry, Biophysics, and Molecular Biology (X.G., H.J., B.J.N.), National Science Foundation Engineering Research Center for Biorenewable Chemicals (X.G., B.J.N.), Department of Statistics (A.L., D.N.), Department of Genetics, Development, and Cellular Biology (L.L.), Laurence H. Baker Center for Bioinformatics and Biological Statistics (X.Z.), and Center for Metabolic Biology (B.J.N.), Iowa State University, Ames, Iowa 50011;
- Metabolomics Research Group, RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.O., K.S.); and
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
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15
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Bond TEH, Sorenson AE, Schaeffer PM. Functional characterisation of Burkholderia pseudomallei biotin protein ligase: A toolkit for anti-melioidosis drug development. Microbiol Res 2017; 199:40-48. [PMID: 28454708 DOI: 10.1016/j.micres.2017.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 03/06/2017] [Accepted: 03/15/2017] [Indexed: 01/17/2023]
Abstract
Burkholderia pseudomallei (Bp) is the causative agent of melioidosis. The bacterium is responsible for 20% of community-acquired sepsis cases and 40% of sepsis-related mortalities in northeast Thailand, and is intrinsically resistant to aminoglycosides, macrolides, rifamycins, cephalosporins, and nonureidopenicillins. There is no vaccine and its diagnosis is problematic. Biotin protein ligase (BirA) which is essential for fatty acid synthesis has been proposed as a drug target in bacteria. Very few bacterial BirA have been characterized, and a better understanding of these enzymes is necessary to further assess their value as drug targets. BirA within the Burkholderia genus have not yet been investigated. We present for the first time the cloning, expression, purification and functional characterisation of the putative Bp BirA and orthologous B. thailandensis (Bt) biotin carboxyl carrier protein (BCCP) substrate. A GFP-tagged Bp BirA was produced and applied for the development of a high-throughput (HT) assay based on our differential scanning fluorimetry of GFP-tagged proteins (DSF-GTP) principle as well as an electrophoretic mobility shift assay. Our biochemical data in combination with the new HT DSF-GTP and biotinylation activity assay could facilitate future drug screening efforts against this drug-resistant organism.
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Affiliation(s)
- Thomas E H Bond
- Comparative Genomics Centre, James Cook University, DB21, James Cook Drive, Townsville, QLD 4811, Australia
| | - Alanna E Sorenson
- Comparative Genomics Centre, James Cook University, DB21, James Cook Drive, Townsville, QLD 4811, Australia
| | - Patrick M Schaeffer
- Comparative Genomics Centre, James Cook University, DB21, James Cook Drive, Townsville, QLD 4811, Australia.
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16
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Ikonomova SP, He Z, Karlsson AJ. A simple and robust approach to immobilization of antibody fragments. J Immunol Methods 2016; 435:7-16. [PMID: 27142477 DOI: 10.1016/j.jim.2016.04.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [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: 07/08/2015] [Revised: 04/06/2016] [Accepted: 04/29/2016] [Indexed: 11/18/2022]
Abstract
Antibody fragments, such as the single-chain variable fragment (scFv), have much potential in research and diagnostics because of their antigen-binding ability similar to a full-sized antibody and their ease of production in microorganisms. Some applications of antibody fragments require immobilization on a surface, and we have established a simple immobilization method that is based on the biotin-streptavidin interaction and does not require a separate purification step. We genetically fused two biotinylation tags-the biotin carboxyl carrier protein (BCCP) or the AviTag minimal sequence-to six different scFvs (scFv13R4, scFvD10, scFv26-10, scFv3, scFv5, and scFv12) for site-specific biotinylation in vivo by endogenous biotin ligases produced by Escherichia coli. The biotinylated scFvs were immobilized onto streptavidin-coated plates directly from cell lysates, and immobilization was detected through enzyme-linked immunosorbent assays. All scFvs fusions were successfully immobilized, and scFvs biotinylated via the BCCP tag tended to immobilize better than those biotinylated via the AviTag, even when biotinylation efficiency was improved with the biotin ligase BirA. The ability of immobilized scFvs to bind antigens was confirmed using scFv13R4 and scFvD10 with their respective targets β-galactosidase and bacteriophage lambda head protein D (gpD). The immobilized scFv13R4 bound to β-galactosidase at the same level for both biotinylation tags when the surface was saturated with the scFv, and immobilized scFvs retained their functionality for at least 100days after immobilization. The simplicity and robustness of our method make it a promising approach for future applications that require antibody fragment immobilization.
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Affiliation(s)
- Svetlana P Ikonomova
- Department of Chemical and Biomolecular Engineering, University of Maryland, 2113 Chemical and Nuclear Engineering Building (#090), College Park, MD 20742, USA
| | - Ziming He
- Department of Chemical and Biomolecular Engineering, University of Maryland, 2113 Chemical and Nuclear Engineering Building (#090), College Park, MD 20742, USA
| | - Amy J Karlsson
- Department of Chemical and Biomolecular Engineering, University of Maryland, 2113 Chemical and Nuclear Engineering Building (#090), College Park, MD 20742, USA.
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17
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Abstract
FabA is proposed to catalyze the dehydration step of chain elongation in fatty acid and undecylprodiginine biosynthesis in Streptomyces coelicolor. Analysis of the S. coelicolor genome has revealed a fabA gene (SCO4636-SCO4637, encoding a heterodimer 3-hydroxyacyl-ACP dehydratase). Herein, we report the identification and characterization of the corresponding gene products. Kinetic analysis has demonstrated that FabA is capable of utilizing various chain lengths of straight- and branched-chain 3-hydroxyacyl-NAC substrates. Additionally, FabA does not discriminate between acyl carrier proteins (ACPs) from primary and secondary metabolism. These data provide the first experimental evidence that FabA has 3-hydroxyacyl-ACP dehydratase activity and processes intermediates for both biosynthetic pathways.
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Affiliation(s)
- Renu Singh
- Department of Chemistry, Portland State University , Portland, Oregon 97201, United States
| | - Kevin A Reynolds
- Department of Chemistry, Portland State University , Portland, Oregon 97201, United States
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18
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Ali SA, Chew YW, Omar TC, Azman N. Use of FabV-Triclosan Plasmid Selection System for Efficient Expression and Production of Recombinant Proteins in Escherichia coli. PLoS One 2015; 10:e0144189. [PMID: 26642325 PMCID: PMC4671583 DOI: 10.1371/journal.pone.0144189] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [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: 08/26/2015] [Accepted: 11/13/2015] [Indexed: 11/21/2022] Open
Abstract
Maintenance of recombinant plasmid vectors in host bacteria relies on the presence of selection antibiotics in the growth media to suppress plasmid -free segregants. However, presence of antibiotic resistance genes and antibiotics themselves is not acceptable in several applications of biotechnology. Previously, we have shown that FabV-Triclosan selection system can be used to select high and medium copy number plasmid vectors in E. coli. Here, we have extended our previous work and demonstrated that expression vectors containing FabV can be used efficiently to express heterologous recombinant proteins in similar or better amounts in E. coli host when compared with expression vectors containing β-lactamase. Use of small amount of non-antibiotic Triclosan as selection agent in growth medium, enhanced plasmid stability, applicability in various culture media, and compatibility with other selection systems for multiple plasmid maintenance are noteworthy features of FabV-Triclosan selection system.
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Affiliation(s)
- Syed A. Ali
- Oncological and Radiological Sciences, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, 13200, Kepala Batas, Pulau Pinang, Malaysia
- * E-mail:
| | - Yik Wei Chew
- Oncological and Radiological Sciences, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, 13200, Kepala Batas, Pulau Pinang, Malaysia
| | - Tasyriq Che Omar
- Oncological and Radiological Sciences, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, 13200, Kepala Batas, Pulau Pinang, Malaysia
| | - Nizuwan Azman
- Division of Research Publications, and Innovation, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, 13200, Kepala Batas, Pulau Pinang, Malaysia
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19
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Qin YJ, Wang PF, Makawana JA, Wang ZC, Wang ZN, Jiang AQ, Zhu HL. Design, synthesis and biological evaluation of metronidazole-thiazole derivatives as antibacterial inhibitors. Bioorg Med Chem Lett 2014; 24:5279-5283. [PMID: 25587588] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A series of metronidazole–thiazole derivatives has been designed, synthesized and evaluated as potential antibacterial inhibitors. All the synthesized compounds were determined by elemental analysis, (1)H NMR and MS. They were also tested for antibacterial activity against Escherichia coli, Bacillus thuringiensis, Bacillus subtilis and Pseudomonas aeruginosa as well as for the inhibition to FabH. The results showed that compound 5 e exhibited the most potent inhibitory activity against E. coli FabH with IC50 of 4.9 lM. Molecular modeling simulation studies were performed in order to predict the biological activity of proposed compounds. Toxicity assay of compounds 5 a, 5 b, 5 d, 5 e, 5 g and 5 i showed that they were noncytotoxic against human macrophage. The results revealed that these compounds offered remarkable viability.
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Affiliation(s)
- Ya-Juan Qin
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science Nanjing University, Nanjing 210093, People’s Republic of China
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20
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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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21
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Jenkins RJ, Heslip KA, Meagher JL, Stuckey JA, Dotson GD. Structural basis for the recognition of peptide RJPXD33 by acyltransferases in lipid A biosynthesis. J Biol Chem 2014; 289:15527-35. [PMID: 24742680 PMCID: PMC4140908 DOI: 10.1074/jbc.m114.564278] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [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: 03/13/2014] [Revised: 04/15/2014] [Indexed: 01/28/2023] Open
Abstract
UDP-N-acetylglucosamine acyltransferase (LpxA) and UDP-3-O-(acyl)-glucosamine acyltransferase (LpxD) constitute the essential, early acyltransferases of lipid A biosynthesis. Recently, an antimicrobial peptide inhibitor, RJPXD33, was identified with dual affinity for LpxA and LpxD. To gain a fundamental understanding of the molecular basis of inhibitor binding, we determined the crystal structure of LpxA from Escherichia coli in complex with RJPXD33 at 1.9 Å resolutions. Our results suggest that the peptide binds in a unique modality that mimics (R)-β-hydroxyacyl pantetheine binding to LpxA and displays how the peptide binds exclusive of the native substrate, acyl-acyl carrier protein. Acyltransferase binding studies with photo-labile RJPXD33 probes and truncations of RJPXD33 validated the structure and provided fundamental insights for future design of small molecule inhibitors. Overlay of the LpxA-RJPXD33 structure with E. coli LpxD identified a complementary peptide binding pocket within LpxD and serves as a model for further biochemical characterization of RJPXD33 binding to LpxD.
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Affiliation(s)
- Ronald J Jenkins
- From the Department of Medicinal Chemistry, College of Pharmacy, and
| | - Kyle A Heslip
- From the Department of Medicinal Chemistry, College of Pharmacy, and
| | - Jennifer L Meagher
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109
| | - Jeanne A Stuckey
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109
| | - Garry D Dotson
- From the Department of Medicinal Chemistry, College of Pharmacy, and
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22
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Belkebir A, Benhassaine-Kesri G. Sethoxydim treatment inhibits lipid metabolism and enhances the accumulation of anthocyanins in rape (Brassica napus L.) leaves. Pestic Biochem Physiol 2013; 107:120-126. [PMID: 25149245 DOI: 10.1016/j.pestbp.2013.06.003] [Citation(s) in RCA: 3] [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: 02/14/2013] [Revised: 06/04/2013] [Accepted: 06/04/2013] [Indexed: 06/03/2023]
Abstract
Cyclohexanediones (e.g., sethoxydim) are known to be inhibitors of plastid acetyl-CoA carboxylase (ACCase) of monocotyledonous plants and provoke plant death. When rape leaves were treated with 10(-3) M sethoxydim, growth rate, chlorophyll and lipid contents were reduced, but plant resisted to herbicide. [1-(14)C] Acetate labelling showed that lipid synthesis was affected by sethoxydim, probably through inhibition of chloroplast homomeric ACCase activity, and the fatty acid synthase activity (FAS) was reduced because of malonyl-CoA deficiency. In contrast, sethoxydim treatment provoked an increase in phenylalanine ammonia lyase (PAL) activity with an accumulation of cinnamic acid, naringenin and anthocyanins. The accumulation of anthocyanins seems to reduce the damaging effect of the herbicide stress. Thus, in plant cell, the flux of carbon seems to be oriented towards protective mechanisms, and the two ACCases could have an important role in this orientation.
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Affiliation(s)
- Aicha Belkebir
- Physiologie Végétale/LBPO, Faculté des Sciences Biologiques, Université des, Sciences et de la Technologie Houari Boumédienne, BP 39, El Alia, Bab Ezzouar, Alger, Algeria
| | - Ghouziel Benhassaine-Kesri
- UPMC Université Paris 6, Physiologie Cellulaire et Moléculaire des Plantes UR5, EAC CNRS 7180, F-75252 Paris cedex 05, France.
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23
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Fukuda N, Ikawa Y, Aoyagi T, Kozaki A. Expression of the genes coding for plastidic acetyl-CoA carboxylase subunits is regulated by a location-sensitive transcription factor binding site. Plant Mol Biol 2013; 82:473-83. [PMID: 23733600 DOI: 10.1007/s11103-013-0075-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 05/14/2013] [Indexed: 05/20/2023]
Abstract
Plastidic acetyl-CoA carboxylase (ACCase) regulates the rate of fatty acid synthesis. This enzyme is composed of biotin carboxyl carrier protein (BCCP), biotin carboxylase (BC), and carboxyltransferase (CT), which consists of α and β subunits. Among these components, CTβ is encoded by the plastidic genome. In Arabidopsis, BC and CTα are each encoded by a single gene, and there are two genes for BCCP, BCCP1 and BCCP2. Promoter analysis revealed that the 5'-UTR containing the AW box is necessary for the expression of these genes in seeds and seedlings. The results indicated that there are other transcription factors besides WRI1 that bind to the AW box and regulate these genes in organs other than seeds. Although the AW boxes at 748 and 532 bp upstream from the transcription start sites (TSSs) of the BC and CTα genes, respectively, were not functional in seeds, the latter was functional in seedlings. In addition, when these AW boxes were moved to approximately 200 bp upstream from the TSS, they became active in seeds but not in seedlings. These results suggest that the distance from the TSS affects the function of the AW box, and the AW box alone is not sufficient for expression in seedlings. A comparison of the protein levels of BC, BCCP1, BCCP2 and CTβ between a wri1 mutant, a WRI1-overexpressing line and control plants showed that protein levels of BCCP2 and BC but not BCCP1 and CTβ are affected by WRI1. The results suggest that ACCase subunits are differentially regulated by WRI1.
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Affiliation(s)
- Natsumi Fukuda
- Department of Biology, Shizuoka University, Suruga-ku, Shizuoka, Japan
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24
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Abstract
Membrane lipid homeostasis is a vital facet of bacterial cell physiology. For decades, research in bacterial lipid synthesis was largely confined to the Escherichia coli model system. This basic research provided a blueprint for the biochemistry of lipid metabolism that has largely defined the individual steps in bacterial fatty acid and phospholipids synthesis. The advent of genomic sequencing has revealed a surprising amount of diversity in the genes, enzymes and genetic organization of the components responsible for bacterial lipid synthesis. Although the chemical steps in fatty acid synthesis are largely conserved in bacteria, there are surprising differences in the structure and cofactor requirements for the enzymes that perform these reactions in Gram-positive and Gram-negative bacteria. This review summarizes how the explosion of new information on the diversity of biochemical and genetic regulatory mechanisms has impacted our understanding of bacterial lipid homeostasis. The potential and problems of developing therapeutics that block pathogen phospholipid synthesis are explored and evaluated. The study of bacterial lipid metabolism continues to be a rich source for new biochemistry that underlies the variety and adaptability of bacterial life styles.
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Affiliation(s)
- Joshua B Parsons
- Department of Infectious Diseases, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
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25
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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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26
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Zhang F, Ouellet M, Batth TS, Adams PD, Petzold CJ, Mukhopadhyay A, Keasling JD. Enhancing fatty acid production by the expression of the regulatory transcription factor FadR. Metab Eng 2012; 14:653-60. [PMID: 23026122 DOI: 10.1016/j.ymben.2012.08.009] [Citation(s) in RCA: 139] [Impact Index Per Article: 11.6] [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: 06/21/2012] [Revised: 08/23/2012] [Accepted: 08/27/2012] [Indexed: 01/17/2023]
Abstract
Fatty acids are important precursors to biofuels. The Escherichia coli FadR is a transcription factor that regulates several processes in fatty acid biosynthesis, degradation, and membrane transport. By tuning the expression of FadR in an engineered E. coli host, we were able to increase fatty acid titer by 7.5-fold over our previously engineered fatty acid-producing strain, reaching 5.2±0.5g/L and 73% of the theoretical yield. The mechanism by which FadR enhanced fatty acid yield was studied by whole-genome transcriptional analysis (microarray) and targeted proteomics. Overexpression of FadR led to transcriptional changes for many genes, including genes involved in fatty acid pathways. The biggest transcriptional changes in fatty acid pathway genes included fabB, fabF, and accA. Overexpression of any of these genes alone did not result in a high yield comparable to fadR expression, indicating that FadR enhanced fatty acid production globally by tuning the expression levels of many genes to optimal levels.
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Affiliation(s)
- Fuzhong Zhang
- Joint BioEnergy Institute, 5885 Hollis Street, Emeryville, CA 94608, USA
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27
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Lombard J, López-García P, Moreira D. An ACP-Independent Fatty Acid Synthesis Pathway in Archaea: Implications for the Origin of Phospholipids. Mol Biol Evol 2012; 29:3261-5. [PMID: 22718911 DOI: 10.1093/molbev/mss160] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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28
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Angelini S, My L, Bouveret E. Disrupting the Acyl Carrier Protein/SpoT interaction in vivo: identification of ACP residues involved in the interaction and consequence on growth. PLoS One 2012; 7:e36111. [PMID: 22558350 PMCID: PMC3340395 DOI: 10.1371/journal.pone.0036111] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [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: 12/20/2011] [Accepted: 03/30/2012] [Indexed: 11/23/2022] Open
Abstract
In bacteria, Acyl Carrier Protein (ACP) is the central cofactor for fatty acid biosynthesis. It carries the acyl chain in elongation and must therefore interact successively with all the enzymes of this pathway. Yet, ACP also interacts with proteins of diverse unrelated function. Among them, the interaction with SpoT has been proposed to be involved in regulating ppGpp levels in the cell in response to fatty acid synthesis inhibition. In order to better understand this mechanism, we screened for ACP mutants unable to interact with SpoT in vivo by bacterial two-hybrid, but still functional for fatty acid synthesis. The position of the selected mutations indicated that the helix II of ACP is responsible for the interaction with SpoT. This suggested a mechanism of recognition similar to one used for the enzymes of fatty acid synthesis. Consistently, the interactions tested by bacterial two-hybrid of ACP with fatty acid synthesis enzymes were also affected by the mutations that prevented the interaction with SpoT. Yet, interestingly, the corresponding mutant strains were viable, and the phenotypes of one mutant suggested a defect in growth regulation.
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Affiliation(s)
- Sandra Angelini
- Laboratory of Macromolecular System Engineering (LISM), Centre National de la Recherche Scientifique (CNRS), Aix-Marseille University, Marseille, France
| | - Laetitia My
- Laboratory of Macromolecular System Engineering (LISM), Centre National de la Recherche Scientifique (CNRS), Aix-Marseille University, Marseille, France
| | - Emmanuelle Bouveret
- Laboratory of Macromolecular System Engineering (LISM), Centre National de la Recherche Scientifique (CNRS), Aix-Marseille University, Marseille, France
- * E-mail:
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29
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Cantaloube S, Veyron-Churlet R, Haddache N, Daffé M, Zerbib D. The Mycobacterium tuberculosis FAS-II dehydratases and methyltransferases define the specificity of the mycolic acid elongation complexes. PLoS One 2011; 6:e29564. [PMID: 22216317 PMCID: PMC3245277 DOI: 10.1371/journal.pone.0029564] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [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: 09/21/2011] [Accepted: 11/30/2011] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND The human pathogen Mycobacterium tuberculosis (Mtb) has the originality of possessing a multifunctional mega-enzyme FAS-I (Fatty Acid Synthase-I), together with a multi-protein FAS-II system, to carry out the biosynthesis of common and of specific long chain fatty acids: the mycolic acids (MA). MA are the main constituents of the external mycomembrane that represents a tight permeability barrier involved in the pathogenicity of Mtb. The MA biosynthesis pathway is essential and contains targets for efficient antibiotics. We have demonstrated previously that proteins of FAS-II interact specifically to form specialized and interconnected complexes. This finding suggested that the organization of FAS-II resemble to the architecture of multifunctional mega-enzyme like the mammalian mFAS-I, which is devoted to the fatty acid biosynthesis. PRINCIPAL FINDINGS Based on conventional and reliable studies using yeast-two hybrid, yeast-three-hybrid and in vitro Co-immunoprecipitation, we completed here the analysis of the composition and architecture of the interactome between the known components of the Mtb FAS-II complexes. We showed that the recently identified dehydratases HadAB and HadBC are part of the FAS-II elongation complexes and may represent a specific link between the core of FAS-II and the condensing enzymes of the system. By testing four additional methyltransferases involved in the biosynthesis of mycolic acids, we demonstrated that they display specific interactions with each type of complexes suggesting their coordinated action during MA elongation. SIGNIFICANCE These results provide a global update of the architecture and organization of a FAS-II system. The FAS-II system of Mtb is organized in specialized interconnected complexes and the specificity of each elongation complex is given by preferential interactions between condensing enzymes and dehydratase heterodimers. This study will probably allow defining essential and specific interactions that correspond to promising targets for Mtb FAS-II inhibitors.
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Affiliation(s)
- Sylvain Cantaloube
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS), Toulouse, France
- Université de Toulouse; Université Paul Sabatier (UPS), Toulouse, France
| | - Romain Veyron-Churlet
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS), Toulouse, France
- Université de Toulouse; Université Paul Sabatier (UPS), Toulouse, France
| | - Nabila Haddache
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS), Toulouse, France
- Université de Toulouse; Université Paul Sabatier (UPS), Toulouse, France
| | - Mamadou Daffé
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS), Toulouse, France
- Université de Toulouse; Université Paul Sabatier (UPS), Toulouse, France
| | - Didier Zerbib
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS), Toulouse, France
- Université de Toulouse; Université Paul Sabatier (UPS), Toulouse, France
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30
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Purushothaman S, Annamalai K, Tyagi AK, Surolia A. Diversity in functional organization of class I and class II biotin protein ligase. PLoS One 2011; 6:e16850. [PMID: 21390227 PMCID: PMC3048393 DOI: 10.1371/journal.pone.0016850] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [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: 08/29/2010] [Accepted: 01/16/2011] [Indexed: 11/28/2022] Open
Abstract
The cell envelope of Mycobacterium tuberculosis
(M.tuberculosis) is composed of a variety of lipids
including mycolic acids, sulpholipids, lipoarabinomannans, etc., which impart
rigidity crucial for its survival and pathogenesis. Acyl CoA carboxylase (ACC)
provides malonyl-CoA and methylmalonyl-CoA, committed precursors for fatty acid
and essential for mycolic acid synthesis respectively. Biotin Protein Ligase
(BPL/BirA) activates apo-biotin carboxyl carrier protein (BCCP) by biotinylating
it to an active holo-BCCP. A minimal peptide (Schatz), an efficient substrate
for Escherichia coli BirA, failed to serve as substrate for
M. tuberculosis Biotin Protein Ligase
(MtBPL). MtBPL specifically biotinylates
homologous BCCP domain, MtBCCP87, but not
EcBCCP87. This is a unique feature of
MtBPL as EcBirA lacks such a stringent
substrate specificity. This feature is also reflected in the lack of
self/promiscuous biotinylation by MtBPL. The N-terminus/HTH
domain of EcBirA has the self-biotinable lysine residue that is
inhibited in the presence of Schatz peptide, a peptide designed to act as a
universal acceptor for EcBirA. This suggests that when biotin
is limiting, EcBirA preferentially catalyzes, biotinylation of
BCCP over self-biotinylation. R118G mutant of EcBirA showed
enhanced self and promiscuous biotinylation but its homologue, R69A
MtBPL did not exhibit these properties. The catalytic
domain of MtBPL was characterized further by limited
proteolysis. Holo-MtBPL is protected from proteolysis by
biotinyl-5′ AMP, an intermediate of MtBPL catalyzed
reaction. In contrast, apo-MtBPL is completely digested by
trypsin within 20 min of co-incubation. Substrate selectivity and inability to
promote self biotinylation are exquisite features of MtBPL and
are a consequence of the unique molecular mechanism of an enzyme adapted for the
high turnover of fatty acid biosynthesis.
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Affiliation(s)
| | | | - Anil K. Tyagi
- Department of Biochemistry, University of
Delhi South Campus, New Delhi, India
| | - Avadhesha Surolia
- Molecular Biophysics Unit, Indian Institute of
Science, Bangalore, India
- National Institute of Immunology, Aruna Asaf
Ali Marg, New Delhi, India
- * E-mail:
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31
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Li X, Ilarslan H, Brachova L, Qian HR, Li L, Che P, Wurtele ES, Nikolau BJ. Reverse-genetic analysis of the two biotin-containing subunit genes of the heteromeric acetyl-coenzyme A carboxylase in Arabidopsis indicates a unidirectional functional redundancy. Plant Physiol 2011; 155:293-314. [PMID: 21030508 PMCID: PMC3075786 DOI: 10.1104/pp.110.165910] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2010] [Accepted: 10/26/2010] [Indexed: 05/19/2023]
Abstract
The heteromeric acetyl-coenzyme A carboxylase catalyzes the first and committed reaction of de novo fatty acid biosynthesis in plastids. This enzyme is composed of four subunits: biotin carboxyl-carrier protein (BCCP), biotin carboxylase, α-carboxyltransferase, and β-carboxyltransferase. With the exception of BCCP, single-copy genes encode these subunits in Arabidopsis (Arabidopsis thaliana). Reverse-genetic approaches were used to individually investigate the physiological significance of the two paralogous BCCP-coding genes, CAC1A (At5g16390, codes for BCCP1) and CAC1B (At5g15530, codes for BCCP2). Transfer DNA insertional alleles that completely eliminate the accumulation of BCCP2 have no perceptible effect on plant growth, development, and fatty acid accumulation. In contrast, transfer DNA insertional null allele of the CAC1A gene is embryo lethal and deleteriously affects pollen development and germination. During seed development the effect of the cac1a null allele first becomes apparent at 3-d after flowering, when the synchronous development of the endosperm and embryo is disrupted. Characterization of CAC1A antisense plants showed that reducing BCCP1 accumulation to 35% of wild-type levels, decreases fatty acid accumulation and severely affects normal vegetative plant growth. Detailed expression analysis by a suite of approaches including in situ RNA hybridization, promoter:reporter transgene expression, and quantitative western blotting reveal that the expression of CAC1B is limited to a subset of the CAC1A-expressing tissues, and CAC1B expression levels are only about one-fifth of CAC1A expression levels. Therefore, a likely explanation for the observed unidirectional redundancy between these two paralogous genes is that whereas the BCCP1 protein can compensate for the lack of BCCP2, the absence of BCCP1 cannot be tolerated as BCCP2 levels are not sufficient to support heteromeric acetyl-coenzyme A carboxylase activity at a level that is required for normal growth and development.
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MESH Headings
- Acetyl-CoA Carboxylase/genetics
- Acetyl-CoA Carboxylase/metabolism
- Alleles
- Arabidopsis/embryology
- Arabidopsis/enzymology
- Arabidopsis/genetics
- Arabidopsis/growth & development
- Arabidopsis/ultrastructure
- Arabidopsis Proteins/genetics
- Arabidopsis Proteins/metabolism
- Biotin/metabolism
- DNA, Bacterial
- Endosperm/enzymology
- Endosperm/growth & development
- Endosperm/ultrastructure
- Fatty Acid Synthase, Type II/genetics
- Fatty Acid Synthase, Type II/metabolism
- Fatty Acids/metabolism
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Gene Knockout Techniques
- Genes, Plant/genetics
- Genes, Recessive/genetics
- Genetic Complementation Test
- Genetic Techniques
- Germination
- Mutation/genetics
- Pollen Tube/enzymology
- Pollen Tube/growth & development
- Pollen Tube/ultrastructure
- Protein Subunits/genetics
- Protein Subunits/metabolism
- RNA, Antisense/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
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Tasdemir D, Sanabria D, Lauinger IL, Tarun A, Herman R, Perozzo R, Zloh M, Kappe SH, Brun R, Carballeira NM. 2-Hexadecynoic acid inhibits plasmodial FAS-II enzymes and arrests erythrocytic and liver stage Plasmodium infections. Bioorg Med Chem 2010; 18:7475-85. [PMID: 20855214 PMCID: PMC2981824 DOI: 10.1016/j.bmc.2010.08.055] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [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] [Received: 06/02/2010] [Revised: 07/14/2010] [Accepted: 08/29/2010] [Indexed: 11/24/2022]
Abstract
Acetylenic fatty acids are known to display several biological activities, but their antimalarial activity has remained unexplored. In this study, we synthesized the 2-, 5-, 6-, and 9-hexadecynoic acids (HDAs) and evaluated their in vitro activity against erythrocytic (blood) stages of Plasmodium falciparum and liver stages of Plasmodium yoelii infections. Since the type II fatty acid biosynthesis pathway (PfFAS-II) has recently been shown to be indispensable for liver stage malaria parasites, the inhibitory potential of the HDAs against multiple P. falciparum FAS-II (PfFAS-II) elongation enzymes was also evaluated. The highest antiplasmodial activity against blood stages of P. falciparum was displayed by 5-HDA (IC(50) value 6.6 μg/ml), whereas the 2-HDA was the only acid arresting the growth of liver stage P. yoelii infection, in both flow cytometric assay (IC(50) value 2-HDA 15.3 μg/ml, control drug atovaquone 2.5 ng/ml) and immunofluorescence analysis (IC(50) 2-HDA 4.88 μg/ml, control drug atovaquone 0.37 ng/ml). 2-HDA showed the best inhibitory activity against the PfFAS-II enzymes PfFabI and PfFabZ with IC(50) values of 0.38 and 0.58 μg/ml (IC(50) control drugs 14 and 30 ng/ml), respectively. Enzyme kinetics and molecular modeling studies revealed valuable insights into the binding mechanism of 2-HDA on the target enzymes. All HDAs showed in vitro activity against Trypanosoma brucei rhodesiense (IC(50) values 3.7-31.7 μg/ml), Trypanosoma cruzi (only 2-HDA, IC(50) 20.2 μg/ml), and Leishmania donovani (IC(50) values 4.1-13.4 μg/ml) with generally low or no significant toxicity on mammalian cells. This is the first study to indicate therapeutic potential of HDAs against various parasitic protozoa. It also points out that the malarial liver stage growth inhibitory effect of the 2-HDA may be promoted via PfFAS-II enzymes. The lack of cytotoxicity, lipophilic nature, and calculated pharmacokinetic properties suggests that 2-HDA could be a useful compound to study the interaction of fatty acids with these key P. falciparum enzymes.
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Affiliation(s)
- Deniz Tasdemir
- Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom.
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33
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Gurvitz A. A C. elegans model for mitochondrial fatty acid synthase II: the longevity-associated gene W09H1.5/mecr-1 encodes a 2-trans-enoyl-thioester reductase. PLoS One 2009; 4:e7791. [PMID: 19924289 PMCID: PMC2774161 DOI: 10.1371/journal.pone.0007791] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [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: 07/08/2009] [Accepted: 10/19/2009] [Indexed: 11/19/2022] Open
Abstract
Our recognition of the mitochondria as being important sites of fatty acid biosynthesis is continuously unfolding, especially in light of new data becoming available on compromised fatty acid synthase type 2 (FASII) in mammals. For example, perturbed regulation of murine 17β-HSD8 encoding a component of the mitochondrial FASII enzyme 3-oxoacyl-thioester reductase is implicated in polycystic kidney disease. In addition, over-expression in mice of the Mecr gene coding for 2-trans-enoyl-thioester reductase, also of mitochondrial FASII, leads to impaired heart function. However, mouse knockouts for mitochondrial FASII have hitherto not been reported and, hence, there is a need to develop alternate metazoan models such as nematodes or fruit flies. Here, the identification of Caenorhabditis elegans W09H1.5/MECR-1 as a 2-trans-enoyl-thioester reductase of mitochondrial FASII is reported. To identify MECR-1, Saccharomyces cerevisiae etr1Δ mutant cells were employed that are devoid of mitochondrial 2-trans-enoyl-thioester reductase Etr1p. These yeast mutants fail to synthesize sufficient levels of lipoic acid or form cytochrome complexes, and cannot respire or grow on non-fermentable carbon sources. A mutant yeast strain ectopically expressing nematode mecr-1 was shown to contain reductase activity and resemble the self-complemented mutant strain for these phenotype characteristics. Since MECR-1 was not intentionally targeted for compartmentalization using a yeast mitochondrial leader sequence, this inferred that the protein represented a physiologically functional mitochondrial 2-trans-enoyl-thioester reductase. In accordance with published findings, RNAi-mediated knockdown of mecr-1 in C. elegans resulted in life span extension, presumably due to mitochondrial dysfunction. Moreover, old mecr-1(RNAi) worms had better internal organ appearance and were more mobile than control worms, indicating a reduced physiological age. This is the first report on RNAi work dedicated specifically to curtailing mitochondrial FASII in metazoans. The availability of affected survivors will help to position C. elegans as an excellent model for future pursuits in the emerging field of mitochondrial FASII research.
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Affiliation(s)
- Aner Gurvitz
- Section of Physiology of Lipid Metabolism, Institute of Physiology, Center for Physiology, Pathophysiology and Immunology, Medical University of Vienna, Vienna, Austria.
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Gurvitz A. A novel circuit overrides Adr1p control during expression of Saccharomyces cerevisiae 2-trans-enoyl-ACP reductase Etr1p of mitochondrial type 2 fatty acid synthase. FEMS Microbiol Lett 2009; 297:255-60. [PMID: 19583790 PMCID: PMC2784040 DOI: 10.1111/j.1574-6968.2009.01688.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The significance of the chronicled role of the yeast transcription factor Adr1p in regulating ETR1 was examined in wild type and isogenic adr1Delta mutant cells. An ETR1-lacZ reporter construct was used to verify Adr1p-dependent gene expression. On solid glycerol medium containing X-gal, wild-type cells expressing the reporter turned blue, whereas the adr1Delta mutants remained white. beta-Galactosidase activity measurements following 24-h cell growth in liquid glycerol medium revealed a 6.5-fold greater expression level of the reporter gene in the wild type compared with the adr1Delta mutant. In contrast, immunoblotting showed that Etr1p abundance was essentially indistinguishable between the two strains whereas Cta1p, whose expression depends on Adr1p, was present in the wild-type cells, but not in the mutants. Moreover, enzyme assays conducted on transformed wild-type and adr1Delta mutant cells expressing a plasmid-borne ETR1 tethered behind the native promoter revealed similar levels of reductase activity, and the lipoic acid content in the two parental strains was equivalent. Hence, while Adr1p influenced the transcription levels of ETR1, it did not alter the abundance of Etr1p, the level of reductase activity, or the cellular amount of lipoic acid. The results point toward a potentially novel layer of control for maintaining physiological levels of lipoic acid.
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Metz JG, Kuner J, Rosenzweig B, Lippmeier JC, Roessler P, Zirkle R. Biochemical characterization of polyunsaturated fatty acid synthesis in Schizochytrium: release of the products as free fatty acids. Plant Physiol Biochem 2009; 47:472-478. [PMID: 19272783 DOI: 10.1016/j.plaphy.2009.02.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 01/16/2009] [Accepted: 02/09/2009] [Indexed: 05/27/2023]
Abstract
In marine bacteria and some thraustochytrids (marine stramenopiles) long-chain polyunsaturated fatty acids (LC-PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are produced de novo by PUFA synthases. These large, multi-domain enzymes carry out the multitude of individual reactions required for conversion of malonyl-CoA to the final LC-PUFA products. Here we report on the release of fatty acids from the PUFA synthase found in Schizochytrium, a thraustochytrid that has been developed as a commercial source for DHA-enriched biomass and oil. Data from in vitro activity assays indicate that the PUFAs are released from the enzyme as free fatty acids (FFAs). Addition of ATP and Mg(2+) to in vitro assays facilitates appearance of radiolabel from (14)C-malonyl-CoA in a triacylglycerol fraction, suggesting the involvement of acyl-CoA synthetases (ACS). Furthermore, addition of triascin C, an inhibitor of ACSs, to the assays blocks this conversion. When the Schizochytrium PUFA synthase is expressed in Escherichia coli, the products of the enzyme accumulate as FFAs, suggesting that the thioesterase activity required for fatty acid release is an integral part of the PUFA synthase.
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Affiliation(s)
- James G Metz
- Martek Biosciences Boulder Corporation, Boulder, CO 80301, USA.
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Abdul-Ghani MA, Muller FL, Liu Y, Chavez AO, Balas B, Zuo P, Chang Z, Tripathy D, Jani R, Molina-Carrion M, Monroy A, Folli F, Van Remmen H, DeFronzo RA. Deleterious action of FA metabolites on ATP synthesis: possible link between lipotoxicity, mitochondrial dysfunction, and insulin resistance. Am J Physiol Endocrinol Metab 2008; 295:E678-85. [PMID: 18593850 DOI: 10.1152/ajpendo.90287.2008] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Insulin resistance is a characteristic feature of type 2 diabetes and obesity. Insulin-resistant individuals manifest multiple disturbances in free fatty acid (FFA) metabolism and have excessive lipid accumulation in insulin target tissues. Although much evidence supports a causal role for altered FFA metabolism in the development of insulin resistance, i.e., "lipotoxicity", the intracellular mechanisms by which elevated plasma FFA levels cause insulin resistance have yet to be completely elucidated. Recent studies have implicated a possible role for mitochondrial dysfunction in the pathogenesis of insulin resistance in skeletal muscle. We examined the effect of FFA metabolites [palmitoyl carnitine (PC), palmitoyl-coenzyme A (CoA), and oleoyl-CoA] on ATP synthesis in mitochondria isolated from mouse and human skeletal muscle. At concentrations ranging from 0.5 to 2 microM, these FFA metabolites stimulated ATP synthesis; however, above 5 microM, there was a dose-response inhibition of ATP synthesis. Furthermore, 10 microM PC inhibits ATP synthesis from pyruvate. Elevated PC concentrations (> or =10 microM) inhibit electron transport chain activity and decrease the mitochondrial inner membrane potential. These acquired mitochondrial defects, caused by a physiological increase in the concentration of FFA metabolites, provide a mechanistic link between lipotoxicity, mitochondrial dysfunction, and muscle insulin resistance.
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Brown AK, Bhatt A, Singh A, Saparia E, Evans AF, Besra GS. Identification of the dehydratase component of the mycobacterial mycolic acid-synthesizing fatty acid synthase-II complex. Microbiology (Reading) 2008; 153:4166-4173. [PMID: 18048930 DOI: 10.1099/mic.0.2007/012419-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Mycolic acids are vital components of the Mycobacterium tuberculosis cell wall and are essential for survival. While most components of the fatty acid synthase-II (FAS-II) enzymic machinery that synthesizes these long chain alpha-alkyl, beta-hydroxy fatty acids have been identified, the gene encoding the beta-hydroxyacyl-acyl carrier protein (ACP) dehydratase activity has remained elusive. Recent bioinformatics-based studies and drug inhibition experiments have identified the M. tuberculosis gene Rv0636 as a promising candidate for this role. Using a recently described, specialized transduction-based genetic tool we now demonstrate that MSMEG1341, the Mycobacterium smegmatis homologue of Rv0636, is an essential gene; null mutants of the gene could only be generated in a merodiploid strain which contained a second integrated acetamide-inducible copy of MSMEG1341. Growth of the conditional mutant in the absence of acetamide resulted in loss of mycolic acid biosynthesis and eventually loss of viability due to cell lysis. Null MSMEG1341 mutants could also be generated in a M. smegmatis strain containing an integrated copy of Rv0636, indicating that Rv0636 was the functional counterpart of MSMEG1341 in M. tuberculosis. Our results demonstrate that MSMEG1341 is an essential gene involved in mycolic acid biosynthesis and encodes the FAS-II beta-hydroxyacyl-ACP dehydratase.
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Affiliation(s)
- Alistair K Brown
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Apoorva Bhatt
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Albel Singh
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Elesh Saparia
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Alex F Evans
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Gurdyal S Besra
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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Lu JZ, Muench SP, Allary M, Campbell S, Roberts CW, Mui E, McLeod RL, Rice DW, Prigge ST. Type I and type II fatty acid biosynthesis in Eimeria tenella: enoyl reductase activity and structure. Parasitology 2007; 134:1949-62. [PMID: 17697396 PMCID: PMC2801558 DOI: 10.1017/s0031182007003319] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [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: 11/06/2022]
Abstract
Apicomplexan parasites of the genus Eimeria are the major causative agent of avian coccidiosis, leading to high economic losses in the poultry industry. Recent results show that Eimeria tenella harbours an apicoplast organelle, and that a key biosynthetic enzyme, enoyl reductase, is located in this organelle. In related parasites, enoyl reductase is one component of a type II fatty acid synthase (FAS) and has proven to be an attractive target for antimicrobial compounds. We cloned and expressed the mature form of E. tenella enoyl reductase (EtENR) for biochemical and structural studies. Recombinant EtENR exhibits NADH-dependent enoyl reductase activity and is inhibited by triclosan with an IC50 value of 60 nm. The crystal structure of EtENR reveals overall similarity with other ENR enzymes; however, the active site of EtENR is unoccupied, a state rarely observed in other ENR structures. Furthermore, the position of the central beta-sheet appears to block NADH binding and would require significant movement to allow NADH binding, a feature not previously seen in the ENR family. We analysed the E. tenella genomic database for orthologues of well-characterized bacterial and apicomplexan FAS enzymes and identified 6 additional genes, suggesting that E. tenella contains a type II FAS capable of synthesizing saturated, but not unsaturated, fatty acids. Interestingly, we also identified sequences that appear to encode multifunctional type I FAS enzymes, a feature also observed in Toxoplasma gondii, highlighting the similarity between these apicomplexan parasites.
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Affiliation(s)
- J. Z. Lu
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - S. P. Muench
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - M. Allary
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - S. Campbell
- Strathclyde Institute of Biomedical Sciences, University of Strathclyde, Glasgow G4 0NR, UK
| | - C. W. Roberts
- Strathclyde Institute of Biomedical Sciences, University of Strathclyde, Glasgow G4 0NR, UK
| | - E. Mui
- Department of Ophthalmology and Visual Sciences, University of Chicago, Chicago, IL 60637, USA
| | - R. L. McLeod
- Department of Ophthalmology and Visual Sciences, University of Chicago, Chicago, IL 60637, USA
- Department of Pediatrics (Infectious Diseases), and Pathology and Committees on Genetics, Molecular Medicine and Immunology and the College, University of Chicago, Chicago, IL 60637, USA
| | - D. W. Rice
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - S. T. Prigge
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
- Corresponding author: Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA. Tel: +1 443 287 4822. Fax: +1 410 955 0105.
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Ferguson DJP, Campbell SA, Henriquez FL, Phan L, Mui E, Richards TA, Muench SP, Allary M, Lu JZ, Prigge ST, Tomley F, Shirley MW, Rice DW, McLeod R, Roberts CW. Enzymes of type II fatty acid synthesis and apicoplast differentiation and division in Eimeria tenella. Int J Parasitol 2006; 37:33-51. [PMID: 17112527 PMCID: PMC2803676 DOI: 10.1016/j.ijpara.2006.10.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [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] [Received: 07/24/2006] [Revised: 09/26/2006] [Accepted: 10/03/2006] [Indexed: 11/16/2022]
Abstract
Apicomplexan parasites, Eimeria tenella, Plasmodium spp. and Toxoplasma gondii, possess a homologous plastid-like organelle termed the apicoplast, derived from the endosymbiotic enslavement of a photosynthetic alga. However, currently no eimerian nuclear encoded apicoplast targeted proteins have been identified, unlike in Plasmodium spp. and T. gondii. In this study, we demonstrate that nuclear encoded enoyl reductase of E. tenella (EtENR) has a predicted N-terminal bipartite transit sequence, typical of apicoplast-targeted proteins. Using a combination of immunocytochemistry and EM we demonstrate that this fatty acid biosynthesis protein is located in the apicoplast of E. tenella. Using the EtENR as a tool to mark apicoplast development during the Eimeria lifecycle, we demonstrate that nuclear and apicoplast division appear to be independent events, both organelles dividing prior to daughter cell formation, with each daughter cell possessing one to four apicoplasts. We believe this is the first report of multiple apicoplasts present in the infectious stage of an apicomplexan parasite. Furthermore, the microgametes lacked an identifiable apicoplast consistent with maternal inheritance via the macrogamete. It was found that the size of the organelle and the abundance of EtENR varied with developmental stage of the E. tenella lifecycle. The high levels of EtENR protein observed during asexual development and macrogametogony is potentially associated with the increased synthesis of fatty acids required for the rapid formation of numerous merozoites and for the extracellular development and survival of the oocyst. Taken together the data demonstrate that the E. tenella apicoplast participates in type II fatty acid biosynthesis with increased expression of ENR during parasite growth. Apicoplast division results in the simultaneous formation of multiple fragments. The division mechanism is unknown, but is independent of nuclear division and occurs prior to daughter formation.
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Affiliation(s)
- D J P Ferguson
- Nuffield Department of Pathology, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK.
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