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Legood S, Boneca IG, Buddelmeijer N. Mode of action of lipoprotein modification enzymes-Novel antibacterial targets. Mol Microbiol 2021; 115:356-365. [PMID: 32979868 PMCID: PMC8048626 DOI: 10.1111/mmi.14610] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/10/2020] [Indexed: 01/04/2023]
Abstract
Lipoproteins are characterized by a fatty acid moiety at their amino-terminus through which they are anchored into membranes. They fulfill a variety of essential functions in bacterial cells, such as cell wall maintenance, virulence, efflux of toxic elements including antibiotics, and uptake of nutrients. The posttranslational modification process of lipoproteins involves the sequential action of integral membrane enzymes and phospholipids as acyl donors. In recent years, the structures of the lipoprotein modification enzymes have been solved by X-ray crystallography leading to a greater insight into their function and the molecular mechanism of the reactions. The catalytic domains of the enzymes are exposed to the periplasm or external milieu and are readily accessible to small molecules. Since the lipoprotein modification pathway is essential in proteobacteria, it is a potential target for the development of novel antibiotics. In this review, we discuss recent literature on the structural characterization of the enzymes, and the in vitro activity assays compatible with high-throughput screening for inhibitors, with perspectives on the development of new antimicrobial agents.
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Affiliation(s)
- Simon Legood
- Institut PasteurUnité Biologie et Génétique de la Paroi BactérienneParisFrance
- CNRS, UMR 2001 « Microbiologie intégrative et Moléculaire »ParisFrance
- INSERM Groupe AvenirParisFrance
- Université de ParisSorbonne Paris CitéParisFrance
| | - Ivo G. Boneca
- Institut PasteurUnité Biologie et Génétique de la Paroi BactérienneParisFrance
- CNRS, UMR 2001 « Microbiologie intégrative et Moléculaire »ParisFrance
- INSERM Groupe AvenirParisFrance
| | - Nienke Buddelmeijer
- Institut PasteurUnité Biologie et Génétique de la Paroi BactérienneParisFrance
- CNRS, UMR 2001 « Microbiologie intégrative et Moléculaire »ParisFrance
- INSERM Groupe AvenirParisFrance
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2
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Abstract
A polar head and an apolar tail chemically characterize surfactants, they show different properties and are categorized by different factors such as head charge and molecular weight. They work by reducing the surface tension between oil and water phases to facilitate the formation of one homogeneous mixture. In this respect, they represent unavoidable ingredients, their main application is in the production of detergents, one of if not the most important categories of cosmetics. Their role is very important, it should be remembered that it was precisely soaps and hygiene that defeated the main infectious diseases at the beginning of the last century. Due to their positive environmental impact, the potential uses of microbial sourced surfactants are actively investigated. These compounds are produced with different mechanisms by microorganisms in the aims to defend themselves from external threats, to improve the mobility in the environment, etc. In the cosmetic field, biosurfactants, restricted in the present work to those described above, can carry high advantages, in comparison to traditional surfactants, especially in the field of sustainable and safer approaches. Besiede this, costs still remain an obsatcle to their diffusion; in this regard, exploration of possible multifunctional actions could help to contain application costs. To highlight their features and possible multifunctional role, on the light of specific biological profiles yet underestimated, we have approached the present review work.
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Xia J, Feng B, Wen G, Xue W, Ma G, Zhang H, Wu S. Bacterial Lipoprotein Biosynthetic Pathway as a Potential Target for Structure-based Design of Antibacterial Agents. Curr Med Chem 2020; 27:1132-1150. [PMID: 30360704 DOI: 10.2174/0929867325666181008143411] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 07/31/2018] [Accepted: 08/15/2018] [Indexed: 12/20/2022]
Abstract
BACKGROUND Antibiotic resistance is currently a serious problem for global public health. To this end, discovery of new antibacterial drugs that interact with novel targets is important. The biosynthesis of lipoproteins is vital to bacterial survival and its inhibitors have shown efficacy against a range of bacteria, thus bacterial lipoprotein biosynthetic pathway is a potential target. METHODS At first, the literature that covered the basic concept of bacterial lipoprotein biosynthetic pathway as well as biochemical characterization of three key enzymes was reviewed. Then, the recently resolved crystal structures of the three enzymes were retrieved from Protein Data Bank (PDB) and the essential residues in the active sites were analyzed. Lastly, all the available specific inhibitors targeting this pathway and their Structure-activity Relationship (SAR) were discussed. RESULTS We briefly introduce the bacterial lipoprotein biosynthetic pathway and describe the structures and functions of three key enzymes in detail. In addition, we present much knowledge on ligand recognition that may facilitate structure-based drug design. Moreover, we focus on the SAR of LspA inhibitors and discuss their potency and drug-likeness. CONCLUSION This review presents a clear background of lipoprotein biosynthetic pathway and provides practical clues for structure-based drug design. In particular, the most up-to-date knowledge on the SAR of lead compounds targeting this pathway would be a good reference for discovery of a novel class of antibacterial agents.
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Affiliation(s)
- Jie Xia
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of New Drug Research and Development, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Bo Feng
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of New Drug Research and Development, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Gang Wen
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of New Drug Research and Development, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Wenjie Xue
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of New Drug Research and Development, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Guixing Ma
- Department of Biology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment and SUSTech-HKU joint laboratories for matrix biology, Southern University of Science and Technology, Shenzhen 518055, China
| | - Hongmin Zhang
- Department of Biology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment and SUSTech-HKU joint laboratories for matrix biology, Southern University of Science and Technology, Shenzhen 518055, China
| | - Song Wu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of New Drug Research and Development, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
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Olatunji S, Yu X, Bailey J, Huang CY, Zapotoczna M, Bowen K, Remškar M, Müller R, Scanlan EM, Geoghegan JA, Olieric V, Caffrey M. Structures of lipoprotein signal peptidase II from Staphylococcus aureus complexed with antibiotics globomycin and myxovirescin. Nat Commun 2020; 11:140. [PMID: 31919415 PMCID: PMC6952399 DOI: 10.1038/s41467-019-13724-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 11/20/2019] [Indexed: 01/22/2023] Open
Abstract
Antimicrobial resistance is a major global threat that calls for new antibiotics. Globomycin and myxovirescin are two natural antibiotics that target the lipoprotein-processing enzyme, LspA, thereby compromising the integrity of the bacterial cell envelope. As part of a project aimed at understanding their mechanism of action and for drug development, we provide high-resolution crystal structures of the enzyme from the human pathogen methicillin-resistant Staphylococcus aureus (MRSA) complexed with globomycin and with myxovirescin. Our results reveal an instance of convergent evolution. The two antibiotics possess different molecular structures. Yet, they appear to inhibit identically as non-cleavable tetrahedral intermediate analogs. Remarkably, the two antibiotics superpose along nineteen contiguous atoms that interact similarly with LspA. This 19-atom motif recapitulates a part of the substrate lipoprotein in its proposed binding mode. Incorporating this motif into a scaffold with suitable pharmacokinetic properties should enable the development of effective antibiotics with built-in resistance hardiness. The enzyme LspA from the human pathogen Staphylococcus aureus (MRSA) contributes to the integrity and function of the bacterial cell envelope. Here, authors provide crystal structures of LspA in complex with two natural antibiotics, which have profoundly different structures but inhibit LspA in an identical way.
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Affiliation(s)
- Samir Olatunji
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Xiaoxiao Yu
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Jonathan Bailey
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Chia-Ying Huang
- Swiss Light Source, Paul Scherrer Institute, CH-5232, Villigen, Switzerland
| | - Marta Zapotoczna
- Moyne Institute of Preventive Medicine, Department of Microbiology, School of Genetics and Microbiology, Trinity College Dublin, Dublin, D02, Ireland
| | - Katherine Bowen
- School of Chemistry, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Maja Remškar
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland, Helmholtz Centre for Infection Research and Department of Pharmacy, Saarland University Campus E8 1, D-66123, Saarbrücken, Germany
| | - Rolf Müller
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland, Helmholtz Centre for Infection Research and Department of Pharmacy, Saarland University Campus E8 1, D-66123, Saarbrücken, Germany
| | - Eoin M Scanlan
- School of Chemistry, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Joan A Geoghegan
- Moyne Institute of Preventive Medicine, Department of Microbiology, School of Genetics and Microbiology, Trinity College Dublin, Dublin, D02, Ireland
| | - Vincent Olieric
- Swiss Light Source, Paul Scherrer Institute, CH-5232, Villigen, Switzerland
| | - Martin Caffrey
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, D02 R590, Ireland.
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Abstract
Covering: up to the end of 2013. Myxobacteria produce a vast range of structurally diverse natural products with prominent biological activities. Here, we provide a detailed description and judge the potential of all antibiotically active myxobacterial compounds as lead structures, pointing out their particularities and, if known, their mode of action. Thus, the review provides an overview of the potential of specific compounds, suitable for future investigations and possible clinical applications.
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Affiliation(s)
- Till F Schäberle
- Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany.
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6
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Myxobacterium-produced antibiotic TA (myxovirescin) inhibits type II signal peptidase. Antimicrob Agents Chemother 2012; 56:2014-21. [PMID: 22232277 DOI: 10.1128/aac.06148-11] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Antibiotic TA is a macrocyclic secondary metabolite produced by myxobacteria that has broad-spectrum bactericidal activity. The structure of TA is unique, and its molecular target is unknown. Here, we sought to elucidate TA's mode of action (MOA) through two parallel genetic approaches. First, chromosomal Escherichia coli TA-resistant mutants were isolated. One mutant that showed specific resistance toward TA was mapped and resulted from an IS4 insertion in the lpp gene, which encodes an abundant outer membrane (Braun's) lipoprotein. In a second approach, the comprehensive E. coli ASKA plasmid library was screened for overexpressing clones that conferred TA(r). This effort resulted in the isolation of the lspA gene, which encodes the type II signal peptidase that cleaves signal sequences from prolipoproteins. In whole cells, TA was shown to inhibit Lpp prolipoprotein processing, similar to the known LspA inhibitor globomycin. Based on genetic evidence and prior globomycin studies, a block in Lpp expression or prevention of Lpp covalent cell wall attachment confers TA(r) by alleviating a toxic buildup of mislocalized pro-Lpp. Taken together, these data argue that LspA is the molecular target of TA. Strikingly, the giant ta biosynthetic gene cluster encodes two lspA paralogs that we hypothesize play a role in producer strain resistance.
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7
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Musiol EM, Weber T. Discrete acyltransferases involved in polyketide biosynthesis. MEDCHEMCOMM 2012. [DOI: 10.1039/c2md20048a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Weissman KJ, Müller R. Myxobacterial secondary metabolites: bioactivities and modes-of-action. Nat Prod Rep 2010; 27:1276-95. [DOI: 10.1039/c001260m] [Citation(s) in RCA: 225] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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9
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A brief tour of myxobacterial secondary metabolism. Bioorg Med Chem 2009; 17:2121-36. [DOI: 10.1016/j.bmc.2008.11.025] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2008] [Revised: 11/07/2008] [Accepted: 11/11/2008] [Indexed: 12/16/2022]
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Simunovic V, Zapp J, Rachid S, Krug D, Meiser P, Müller R. Myxovirescin A Biosynthesis is Directed by Hybrid Polyketide Synthases/Nonribosomal Peptide Synthetase, 3-Hydroxy-3-Methylglutaryl-CoA Synthases, and trans-Acting Acyltransferases. Chembiochem 2006; 7:1206-20. [PMID: 16835859 DOI: 10.1002/cbic.200600075] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Myxococcus xanthus DK1622 is shown to be a producer of myxovirescin (antibiotic TA) antibiotics. The myxovirescin biosynthetic gene cluster spans at least 21 open reading frames (ORFs) and covers a chromosomal region of approximately 83 kb. In silico analysis of myxovirescin ORFs in conjunction with genetic studies suggests the involvement of four type I polyketide synthases (PKSs; TaI, TaL, TaO, and TaP), one major hybrid PKS/NRPS (Ta-1), and a number of monofunctional enzymes similar to the ones involved in type II fatty-acid biosynthesis (FAB). Whereas deletion of either taI or taL causes a dramatic drop in myxovirescin production, deletion of both genes (DeltataIL) leads to the complete loss of myxovirescin production. These results suggest that both TaI and TaL PKSs might act in conjunction with a methyltransferase, reductases, and a monooxygenase to produce the 2-hydroxyvaleryl-S-ACP starter that is proposed to act as the biosynthetic primer in the initial condensation reaction with glycine. Polymerization of the remaining 11 acetates required for lactone formation is directed by 12 modules of Ta-1, TaO, and TaP megasynthetases. All modules, except for the first module of TaL, lack cognate acyltransferase (AT) domains. Furthermore, deletion of a discrete tandem AT-encoded by taV-blocks myxovirescin production; this suggests an "in trans" mode of action. To embellish the macrocycle with methyl and ethyl moieties, assembly of the myxovirescin scaffold is proposed to switch twice from PKS to 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA)-like biochemistry during biosynthesis. Disruption of the S-adenosylmethionine (SAM)-dependent methyltransferase, TaQ, shifts production toward two novel myxovirescin analogues, designated myxovirescin Q(a) and myxovirescin Q(c). NMR analysis of purified myxovirescin Q(a) revealed the loss of the methoxy carbon atom. This novel analogue lacks bioactivity against E. coli.
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Affiliation(s)
- Vesna Simunovic
- Pharmaceutical Biotechnology, Saarland University, Im Stadtwald, 66123 Saarbrücken, Germany
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11
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Varon M, Paitan Y, Rosenberg E. Trans-acting regulation of antibiotic TA genes in Myxococcus xanthus. FEMS Microbiol Lett 2006. [DOI: 10.1111/j.1574-6968.1997.tb13870.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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12
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Du L, Cheng YQ, Ingenhorst G, Tang GL, Huang Y, Shen B. Hybrid peptide-polyketide natural products: biosynthesis and prospects towards engineering novel molecules. GENETIC ENGINEERING 2004; 25:227-67. [PMID: 15260241 DOI: 10.1007/978-1-4615-0073-5_11] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Affiliation(s)
- Liangcheng Du
- Department of Chemistry, University of Nebraska, Lincoln, NE 68588, USA
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13
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Paitan Y, Orr E, Ron EZ, Rosenberg E. An unusual beta-ketoacyl:acyl carrier protein synthase and acyltransferase motifs in TaK, a putative protein required for biosynthesis of the antibiotic TA in Myxococcus xanthus. FEMS Microbiol Lett 2001; 203:191-7. [PMID: 11583847 DOI: 10.1111/j.1574-6968.2001.tb10840.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The antibiotic TA of Myxococcus xanthus is produced by a type-I polyketide synthase mechanism. Previous studies have indicated that TA genes are clustered within a 36-kb region. The chemical structure of TA indicates the need for several post-modification steps, which are introduced to form the final bioactive molecule. These include three C-methylations, an O-methylation and a specific hydroxylation. In this study, we describe the genetic analysis of taK, encoding a specific polyketide beta-ketoacyl:acyl carrier protein synthase, which contains an unusual beta-ketoacyl synthase and acyltransferase motifs and is likely to be involved in antibiotic TA post-modification. Functional analysis of this beta-ketoacyl:acyl carrier protein synthase by specific gene disruption suggests that it is essential for the production of an active TA molecule.
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Affiliation(s)
- Y Paitan
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
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Simhi E, van der Mei HC, Ron EZ, Rosenberg E, Busscher HJ. Effect of the adhesive antibiotic TA on adhesion and initial growth of E. coli on silicone rubber. FEMS Microbiol Lett 2000; 192:97-100. [PMID: 11040435 DOI: 10.1111/j.1574-6968.2000.tb09365.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Catheter-associated urinary tract infection is the most common nosocomial infection, and contributes to patient morbidity and mortality. We investigated the effect that the TA adhesive antibiotic had on adhesion and initial growth in urine of Escherichia coli on silicone rubber. The TA antibiotic had reduced adhesion, and inhibited initial growth of the bacteria on the surface. Since adhesion and initial growth on the surface are an essential part of biofilm formation and subsequent infection, we speculate that the TA antibiotic coating might decrease the infection rate associated with indwelling urinary catheter.
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Affiliation(s)
- E Simhi
- Schneider Children's Medical Center of Israel, Petah-Tikva, Israel.
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15
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Paitan Y, Orr E, Ron EZ, Rosenberg E. Genetic and functional analysis of genes required for the post-modification of the polyketide antibiotic TA of Myxococcus xanthus. MICROBIOLOGY (READING, ENGLAND) 1999; 145 ( Pt 11):3059-3067. [PMID: 10589713 DOI: 10.1099/00221287-145-11-3059] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The antibiotic TA of Myxococcus xanthus is a complex macrocyclic polyketide, produced through successive condensations of acetate by a type I PKS (polyketide synthase) mechanism. The genes encoding TA biosynthesis are clustered on a 36 kb DNA fragment, which has been cloned and analysed. The chemical structure of TA and the mechanism by which it is synthesized indicate the need for several post-modification steps, which are introduced into the carbon chain of the polyketide to form the final bioactive molecule. These include the addition of several carbon atoms originating from acetate carbonyl, three C-methylations, O-methylation and a specific hydroxylation. This paper reports the analysis of five genes which are involved in the post-modification of TA. Their functional analysis, by specific gene disruption, suggests that they may be essential for the production of the active antibiotic. The characteristics and organization of the genes suggest that they may be involved in the addition of the carbon atoms which arise from acetate.
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Affiliation(s)
- Yossi Paitan
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel1
| | - Elisha Orr
- Department of Genetics, University of Leicester, Leicester LE1 7RH, UK2
| | - Eliora Z Ron
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel1
| | - Eugene Rosenberg
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel1
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Paitan Y, Alon G, Orr E, Ron EZ, Rosenberg E. The first gene in the biosynthesis of the polyketide antibiotic TA of Myxococcus xanthus codes for a unique PKS module coupled to a peptide synthetase. J Mol Biol 1999; 286:465-74. [PMID: 9973564 DOI: 10.1006/jmbi.1998.2478] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The polyketide antibiotic TA is synthesized by the Gram negative bacterium Myxococcus xanthus in a multi-step process in which a unique glycine-derived molecule is used as a starter unit and elongated through the condensation of 11 acetate molecules by polyketide synthases (PKSs). Analysis of a 7.2 kb DNA fragment, encoding the protein that carries out the first condensation step, revealed that the fragment constitutes a single open reading frame, referred to as Ta1, which lacks the 5' and 3' ends and displays two regions of similarity to other proteins. The first 1020 amino acid residues at the N terminus of the polypeptide are similar to sequences of the large family of enzymes encoding peptide synthetases. They are followed by a second region displaying a high degree of similarity to type I PKS genes. The genetic analysis of this open reading frame is compatible with the proposed chemical structure of TA. The data indicate that the genes encoding TA have a modular gene organization, typical of a type I PKS system. The unusual feature of Ta1 is that the first PKS module of TA resides on the same polypeptide as the peptide synthetase functional unit.
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Affiliation(s)
- Y Paitan
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
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Paitan Y, Orr E, Ron EZ, Rosenberg E. A NusG-like transcription anti-terminator is involved in the biosynthesis of the polyketide antibiotic TA of Myxococcus xanthus. FEMS Microbiol Lett 1999; 170:221-7. [PMID: 9919671 DOI: 10.1111/j.1574-6968.1999.tb13377.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The antibiotic TA of Myxococcus xanthus is synthesized through a type I polyketide synthase mechanism. Previous studies have indicated that several genes essential for TA production are clustered within a 40-kb region and are transcriptionally co-regulated. In this study, we report the genetic analysis of the first gene in the TA gene cluster, identified as a NusG-like transcription anti-terminator. Functional analysis of this NusG-like anti-terminator gene by specific gene disruption confirms that it is essential for TA production but not for normal growth and development.
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Affiliation(s)
- Y Paitan
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ruamat Aviv, Israel
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18
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Affiliation(s)
- C H Drisko
- Department of Periodontics, Endodontics, and Dental Hygiene, University of Louisville, Kentucky, USA
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19
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Autocides and a paracide, antibiotic TA, produced byMyxococcus xanthus. J Ind Microbiol Biotechnol 1996. [DOI: 10.1007/bf01574773] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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20
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Varon M, Rosenberg E. Transcriptional regulation of genes required for antibiotic TA synthesis inMyxococcus xanthus. FEMS Microbiol Lett 1996. [DOI: 10.1111/j.1574-6968.1996.tb08050.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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21
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Varon M, Fuchs N, Monosov M, Tolchinsky S, Rosenberg E. Mutation and mapping of genes involved in production of the antibiotic TA in Myxococcus xanthus. Antimicrob Agents Chemother 1992; 36:2316-21. [PMID: 1332595 PMCID: PMC245495 DOI: 10.1128/aac.36.10.2316] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Transposition of TnV and Tn5lac into Myxococcus xanthus yielded 8,381 kanamycin-resistant mutants that were tested for antibiotic TA production. Twenty-four of the mutants were nonproducers of TA (less than 0.4 ng/ml), and 3 produced a higher level (2.5 micrograms/ml) than the parent strain (1.5 micrograms/ml). For most of the strains, there was 100% cotransduction between kanamycin resistance and the altered TA phenotype. Southern blot analysis of restriction digests of the mutant DNA indicated that the transposons were inserted at different sites on the M. xanthus chromosome. The TA genes were mapped by cotransduction between pairs of mutants following replacement of the initial insert of one of the pair with the tetracycline resistance transposon Tn5-132. Nine of the 13 nonproducers tested were linked over a 36-kb stretch of the chromosome. There was no linkage between one of the overproducers and any of the nonproducers tested.
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Affiliation(s)
- M Varon
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
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