1
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van der Klugt T, van den Biggelaar RHGA, Saris A. Host and bacterial lipid metabolism during tuberculosis infections: possibilities to synergise host- and bacteria-directed therapies. Crit Rev Microbiol 2024:1-21. [PMID: 38916142 DOI: 10.1080/1040841x.2024.2370979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 06/10/2024] [Accepted: 06/11/2024] [Indexed: 06/26/2024]
Abstract
Mycobacterium tuberculosis (Mtb) is the causative pathogen of tuberculosis, the most lethal infectious disease resulting in 1.3 million deaths annually. Treatments against Mtb are increasingly impaired by the growing prevalence of antimicrobial drug resistance, which necessitates the development of new antibiotics or alternative therapeutic approaches. Upon infecting host cells, predominantly macrophages, Mtb becomes critically dependent on lipids as a source of nutrients. Additionally, Mtb produces numerous lipid-based virulence factors that contribute to the pathogen's ability to interfere with the host's immune responses and to create a lipid rich environment for itself. As lipids, lipid metabolism and manipulating host lipid metabolism play an important role for the virulence of Mtb, this review provides a state-of-the-art overview of mycobacterial lipid metabolism and concomitant role of host metabolism and host-pathogen interaction therein. While doing so, we will emphasize unexploited bacteria-directed and host-directed drug targets, and highlight potential synergistic drug combinations that hold promise for the development of new therapeutic interventions.
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Affiliation(s)
- Teun van der Klugt
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Anno Saris
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
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2
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Jian X, Pang F, Hobson C, Jenner M, Alkhalaf LM, Challis GL. Antibiotic Skeletal Diversification via Differential Enoylreductase Recruitment and Module Iteration in trans-Acyltransferase Polyketide Synthases. J Am Chem Soc 2024; 146:6114-6124. [PMID: 38389455 PMCID: PMC10921412 DOI: 10.1021/jacs.3c13667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 02/01/2024] [Accepted: 02/06/2024] [Indexed: 02/24/2024]
Abstract
Microorganisms are remarkable chemists capable of assembling complex molecular architectures that penetrate cells and bind biomolecular targets with exquisite selectivity. Consequently, microbial natural products have wide-ranging applications in medicine and agriculture. How the "blind watchmaker" of evolution creates skeletal diversity is a key question in natural products research. Comparative analysis of biosynthetic pathways to structurally related metabolites is an insightful approach to addressing this. Here, we report comparative biosynthetic investigations of gladiolin, a polyketide antibiotic from Burkholderia gladioli with promising activity against multidrug-resistant Mycobacterium tuberculosis, and etnangien, a structurally related antibiotic produced by Sorangium cellulosum. Although these metabolites have very similar macrolide cores, their C21 side chains differ significantly in both length and degree of saturation. Surprisingly, the trans-acyltransferase polyketide synthases (PKSs) that assemble these antibiotics are almost identical, raising intriguing questions about mechanisms underlying structural diversification in this important class of biosynthetic assembly line. In vitro reconstitution of key biosynthetic transformations using simplified substrate analogues, combined with gene deletion and complementation experiments, enabled us to elucidate the origin of all the structural differences in the C21 side chains of gladiolin and etnangien. The more saturated gladiolin side chain arises from a cis-acting enoylreductase (ER) domain in module 1 and in trans recruitment of a standalone ER to module 5 of the PKS. Remarkably, module 5 of the gladiolin PKS is intrinsically iterative in the absence of the standalone ER, accounting for the longer side chain in etnangien. These findings have important implications for biosynthetic engineering approaches to the creation of novel polyketide skeletons.
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Affiliation(s)
- Xinyun Jian
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
- Warwick
Integrative Synthetic Biology Centre, University
of Warwick, Coventry CV4 7AL, U.K.
- Department
of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
- ARC
Centre of Excellence for Innovations in Protein and Peptide Science, Monash University, Clayton, VIC 3800, Australia
| | - Fang Pang
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
| | - Christian Hobson
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
| | - Matthew Jenner
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
- Warwick
Integrative Synthetic Biology Centre, University
of Warwick, Coventry CV4 7AL, U.K.
| | - Lona M. Alkhalaf
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
| | - Gregory L. Challis
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
- Warwick
Integrative Synthetic Biology Centre, University
of Warwick, Coventry CV4 7AL, U.K.
- Department
of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
- ARC
Centre of Excellence for Innovations in Protein and Peptide Science, Monash University, Clayton, VIC 3800, Australia
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3
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Rens C, Chao JD, Sexton DL, Tocheva EI, Av-Gay Y. Roles for phthiocerol dimycocerosate lipids in Mycobacterium tuberculosis pathogenesis. MICROBIOLOGY-SGM 2021; 167. [PMID: 33629944 DOI: 10.1099/mic.0.001042] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The success of Mycobacterium tuberculosis as a pathogen is well established: tuberculosis is the leading cause of death by a single infectious agent worldwide. The threat of multi- and extensively drug-resistant bacteria has renewed global concerns about this pathogen and understanding its virulence strategies will be essential in the fight against tuberculosis. The current review will focus on phthiocerol dimycocerosates (PDIMs), a long-known and well-studied group of complex lipids found in the M. tuberculosis cell envelope. Numerous studies show a role for PDIMs in several key steps of M. tuberculosis pathogenesis, with recent studies highlighting its involvement in bacterial virulence, in association with the ESX-1 secretion system. Yet, the mechanisms by which PDIMs help M. tuberculosis to control macrophage phagocytosis, inhibit phagosome acidification and modulate host innate immunity, remain to be fully elucidated.
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Affiliation(s)
- Céline Rens
- Division of Infectious Disease, Department of Medicine, The University of British Columbia, Vancouver, Canada
| | - Joseph D Chao
- Division of Infectious Disease, Department of Medicine, The University of British Columbia, Vancouver, Canada
| | - Danielle L Sexton
- Department of Microbiology & Immunology, The University of British Columbia, Vancouver, Canada
| | - Elitza I Tocheva
- Department of Microbiology & Immunology, The University of British Columbia, Vancouver, Canada
| | - Yossef Av-Gay
- Division of Infectious Disease, Department of Medicine, The University of British Columbia, Vancouver, Canada.,Department of Microbiology & Immunology, The University of British Columbia, Vancouver, Canada
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4
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De Majumdar S, Sikri K, Ghosh P, Jaisinghani N, Nandi M, Gandotra S, Mande S, Tyagi JS. Genome analysis identifies a spontaneous nonsense mutation in ppsD leading to attenuation of virulence in laboratory-manipulated Mycobacterium tuberculosis. BMC Genomics 2019; 20:129. [PMID: 30755157 PMCID: PMC6373159 DOI: 10.1186/s12864-019-5482-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 01/24/2019] [Indexed: 01/08/2023] Open
Abstract
Background A previous laboratory study involving wild type, mutant and devR/dosR complemented strains of Mycobacterium tuberculosis reported the attenuation phenotype of complemented strain, Comp1. This phenotype was intriguing since the parental strain H37Rv, devR mutant (Mut1) and additional complemented strains, Comp9 and Comp11, were virulent in the guinea pig model. Results Towards deciphering the mechanism underlying the attenuation of Comp1, a whole genome sequencing approach was undertaken. Eight Single Nucleotide Polymorphisms (SNPs) unique to the Comp1 strain were identified. Of these, 5 SNPs were non-synonymous and included a G➞A mutation resulting in a W1591Stop mutation in ppsD gene of the phthiocerol dimycocerosate (PDIM) biosynthetic cluster. Targeted sequence analysis confirmed this mutation in only Comp1 strain and not in wild type (H37Rv), devR knockout (Mut1) or other complemented (Comp9 and Comp11) bacteria. Differential expression of the PDIM locus in Comp1 bacteria was observed which was associated with a partial deficiency of PDIM, an increased sensitivity to detergent and a compromised ability to infect human THP-1 cells. Conclusions It is proposed that a spontaneous mutation in the ppsD gene of Comp1 underlies down-modulation of the PDIM locus which is associated with defects in permeability and infectivity as well as virulence attenuation in guinea pigs. Our study demonstrates the value of whole genome sequencing for resolving unexplainable bacterial phenotypes and recommends the assessment of PDIM status while assessing virulence properties of laboratory-manipulated strains of M. tuberculosis. Electronic supplementary material The online version of this article (10.1186/s12864-019-5482-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shyamasree De Majumdar
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India.,Present affiliation: School of Biomedical Sciences, Ulster University, Coleraine, UK
| | - Kriti Sikri
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India
| | - Payel Ghosh
- Bioinformatics Center, Savitribai Phule Pune University, Pune, Maharashtra, India
| | - Neetika Jaisinghani
- Cardiorespiratory Disease Biology Unit, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Malobi Nandi
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India.,Amity Institute of Biotechnology, Amity University, Noida, Haryana, India
| | - Sheetal Gandotra
- Cardiorespiratory Disease Biology Unit, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Shekhar Mande
- National Center for Cell Science, University of Pune Campus, Pune, Maharashtra, India
| | - Jaya Sivaswami Tyagi
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India. .,Centre for Bio-design and Diagnostics, Translational Health Science and Technology Institute, Faridabad, Haryana, India.
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5
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Faille A, Gavalda S, Slama N, Lherbet C, Maveyraud L, Guillet V, Laval F, Quémard A, Mourey L, Pedelacq JD. Insights into Substrate Modification by Dehydratases from Type I Polyketide Synthases. J Mol Biol 2017; 429:1554-1569. [PMID: 28377293 DOI: 10.1016/j.jmb.2017.03.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 03/21/2017] [Accepted: 03/27/2017] [Indexed: 02/04/2023]
Abstract
Dehydration reactions play a crucial role in the de novo biosynthesis of fatty acids and a wide range of pharmacologically active polyketide natural products with strong emphasis on human medicine. The type I polyketide synthase PpsC from Mycobacterium tuberculosis catalyzes key biosynthetic steps of lipid virulence factors phthiocerol dimycocerosates and phenolic glycolipids. Given the insolubility of the natural C28-C30 fatty acyl substrate of the PpsC dehydratase (DH) domain, we investigated its structure-function relationships in the presence of shorter surrogate substrates. Since most enzymes belonging to the (R)-specific enoyl hydratase/hydroxyacyl dehydratase family conduct the reverse hydration reaction in vitro, we have determined the X-ray structures of the PpsC DH domain, both unliganded (apo) and in complex with trans-but-2-enoyl-CoA or trans-dodec-2-enoyl-CoA derivatives. This study provides for the first time a snapshot of dehydratase-ligand interactions following a hydration reaction. Our structural analysis allowed us to identify residues essential for substrate binding and activity. The structural comparison of the two complexes also sheds light on the need for long acyl chains for this dehydratase to carry out its function, consistent with both its in vitro catalytic behavior and the physiological role of the PpsC enzyme.
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Affiliation(s)
- Alexandre Faille
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse Cedex 04, France
| | - Sabine Gavalda
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse Cedex 04, France
| | - Nawel Slama
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse Cedex 04, France
| | | | - Laurent Maveyraud
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse Cedex 04, France
| | - Valérie Guillet
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse Cedex 04, France
| | - Françoise Laval
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse Cedex 04, France
| | - Annaïk Quémard
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse Cedex 04, France
| | - Lionel Mourey
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse Cedex 04, France.
| | - Jean-Denis Pedelacq
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse Cedex 04, France.
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6
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Augenstreich J, Arbues A, Simeone R, Haanappel E, Wegener A, Sayes F, Le Chevalier F, Chalut C, Malaga W, Guilhot C, Brosch R, Astarie-Dequeker C. ESX-1 and phthiocerol dimycocerosates of Mycobacterium tuberculosis act in concert to cause phagosomal rupture and host cell apoptosis. Cell Microbiol 2017; 19. [PMID: 28095608 DOI: 10.1111/cmi.12726] [Citation(s) in RCA: 138] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 01/12/2017] [Accepted: 01/14/2017] [Indexed: 12/20/2022]
Abstract
Although phthiocerol dimycocerosates (DIM) are major virulence factors of Mycobacterium tuberculosis (Mtb), the causative agent of human tuberculosis, little is known about their mechanism of action. Localized in the outer membrane of mycobacterial pathogens, DIM are predicted to interact with host cell membranes. Interaction with eukaryotic membranes is a property shared with another virulence factor of Mtb, the early secretory antigenic target EsxA (also known as ESAT-6). This small protein, which is secreted by the type VII secretion system ESX-1 (T7SS/ESX-1), is involved in phagosomal rupture and cell death induced by virulent mycobacteria inside host phagocytes. In this work, by the use of several knock-out or knock-in mutants of Mtb or Mycobacterium bovis BCG strains and different cell biological assays, we present conclusive evidence that ESX-1 and DIM act in concert to induce phagosomal membrane damage and rupture in infected macrophages, ultimately leading to host cell apoptosis. These results identify an as yet unknown function for DIM in the infection process and open up a new research field for the study of the interaction of lipid and protein virulence factors of Mtb.
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Affiliation(s)
- Jacques Augenstreich
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS-Université de Toulouse (UPS), Toulouse, France
| | - Ainhoa Arbues
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS-Université de Toulouse (UPS), Toulouse, France
| | - Roxane Simeone
- Unit for Integrated Mycobacterial Pathogenomics, Institut Pasteur, Paris, France
| | - Evert Haanappel
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS-Université de Toulouse (UPS), Toulouse, France
| | - Alice Wegener
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS-Université de Toulouse (UPS), Toulouse, France
| | - Fadel Sayes
- Unit for Integrated Mycobacterial Pathogenomics, Institut Pasteur, Paris, France
| | - Fabien Le Chevalier
- Unit for Integrated Mycobacterial Pathogenomics, Institut Pasteur, Paris, France
| | - Christian Chalut
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS-Université de Toulouse (UPS), Toulouse, France
| | - Wladimir Malaga
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS-Université de Toulouse (UPS), Toulouse, France
| | - Christophe Guilhot
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS-Université de Toulouse (UPS), Toulouse, France
| | - Roland Brosch
- Unit for Integrated Mycobacterial Pathogenomics, Institut Pasteur, Paris, France
| | - Catherine Astarie-Dequeker
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS-Université de Toulouse (UPS), Toulouse, France
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7
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Abstract
This article summarizes what is currently known of the structures, physiological roles, involvement in pathogenicity, and biogenesis of a variety of noncovalently bound cell envelope lipids and glycoconjugates of Mycobacterium tuberculosis and other Mycobacterium species. Topics addressed in this article include phospholipids; phosphatidylinositol mannosides; triglycerides; isoprenoids and related compounds (polyprenyl phosphate, menaquinones, carotenoids, noncarotenoid cyclic isoprenoids); acyltrehaloses (lipooligosaccharides, trehalose mono- and di-mycolates, sulfolipids, di- and poly-acyltrehaloses); mannosyl-beta-1-phosphomycoketides; glycopeptidolipids; phthiocerol dimycocerosates, para-hydroxybenzoic acids, and phenolic glycolipids; mycobactins; mycolactones; and capsular polysaccharides.
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8
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Flentie KN, Stallings CL, Turk J, Minnaard AJ, Hsu FF. Characterization of phthiocerol and phthiodiolone dimycocerosate esters of M. tuberculosis by multiple-stage linear ion-trap MS. J Lipid Res 2016; 57:142-55. [PMID: 26574042 PMCID: PMC4689332 DOI: 10.1194/jlr.d063735] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 11/13/2015] [Indexed: 12/29/2022] Open
Abstract
Both phthiocerol/phthiodiolone dimycocerosate (PDIM) and phenolic glycolipids are abundant virulent lipids in the cell wall of various pathogenic mycobacteria, which can synthesize a wide range of complex high-molecular-mass lipids. In this article, we describe linear ion-trap MS(n) mass spectrometric approach for structural study of PDIMs, which were desorbed as the [M + Li](+) and [M + NH(4)](+) ions by ESI. We also applied charge-switch strategy to convert the mycocerosic acid substituents to their N-(4-aminomethylphenyl) pyridinium (AMPP) derivatives and analyzed them as M (+) ions, following alkaline hydrolysis of the PDIM to release mycocerosic acids. The structural information from MS(n) on the [M + Li](+) and [M + NH(4)](+) molecular species and on the M (+) ions of the mycocerosic acid-AMPP derivative affords realization of the complex structures of PDIMs in Mycobacterium tuberculosis biofilm, differentiation of phthiocerol and phthiodiolone lipid families and complete structure identification, including the phthiocerol and phthiodiolone backbones, and the mycocerosic acid substituents, including the locations of their multiple methyl side chains, can be achieved.
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Affiliation(s)
- Kelly N Flentie
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO
| | - Christina L Stallings
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO
| | - John Turk
- Mass Spectrometry Resource, Division of Endocrinology, Diabetes, Metabolism, and Lipid Research, Department of Internal Medicine
| | - Adriaan J Minnaard
- Stratingh Institute for Chemistry, University of Groningen, Groningen, The Netherlands
| | - Fong-Fu Hsu
- Mass Spectrometry Resource, Division of Endocrinology, Diabetes, Metabolism, and Lipid Research, Department of Internal Medicine,
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9
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Wang J, Behr MA. Building a better bacillus: the emergence of Mycobacterium tuberculosis. Front Microbiol 2014; 5:139. [PMID: 24765091 PMCID: PMC3982062 DOI: 10.3389/fmicb.2014.00139] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 03/18/2014] [Indexed: 11/29/2022] Open
Abstract
The genus Mycobacterium is comprised of more than 150 species that reside in a wide variety of habitats. Most mycobacteria are environmental organisms that are either not associated with disease or are opportunistic pathogens that cause non-transmissible disease in immunocompromised individuals. In contrast, a small number of species, such as the tubercle bacillus, Mycobacterium tuberculosis, are host-adapted pathogens for which there is no known environmental reservoir. In recent years, gene disruption studies using the host-adapted pathogen have uncovered a number of “virulence factors,” yet genomic data indicate that many of these elements are present in non-pathogenic mycobacteria. This suggests that much of the genetic make-up that enables virulence in the host-adapted pathogen is already present in environmental members of the genus. In addition to these generic factors, we hypothesize that molecules elaborated exclusively by professional pathogens may be particularly implicated in the ability of M. tuberculosis to infect, persist, and cause transmissible pathology in its host species, Homo sapiens. One approach to identify these molecules is to employ comparative analysis of mycobacterial genomes, to define evolutionary events such as horizontal gene transfer (HGT) that contributed M. tuberculosis-specific genetic elements. Independent studies have now revealed the presence of HGT genes in the M. tuberculosis genome and their role in the pathogenesis of disease is the subject of ongoing investigations. Here we review these studies, focusing on the hypothesized role played by HGT loci in the emergence of M. tuberculosis from a related environmental species into a highly specialized human-adapted pathogen.
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Affiliation(s)
- Joyce Wang
- Department of Microbiology and Immunology, McGill University Montreal, QC, Canada
| | - Marcel A Behr
- Department of Microbiology and Immunology, McGill University Montreal, QC, Canada ; Department of Medicine, McGill University Montreal, QC, Canada ; McGill International TB Centre Montreal, QC, Canada
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10
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Quadri LEN. Biosynthesis of mycobacterial lipids by polyketide synthases and beyond. Crit Rev Biochem Mol Biol 2014; 49:179-211. [DOI: 10.3109/10409238.2014.896859] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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11
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Hoang NH, Huong NL, Shrestha A, Sohng JK, Yoon YJ, Park JW. Regio-selectively reduced streptogramin A analogue, 5,6-dihydrovirginiamycin M1 exhibits improved potency against MRSA. Lett Appl Microbiol 2013; 57:393-8. [PMID: 23815812 DOI: 10.1111/lam.12125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 06/21/2013] [Accepted: 06/24/2013] [Indexed: 11/29/2022]
Abstract
A newly reduced macrocyclic lactone antibiotic streptogramin A, 5,6-dihydrovirginiamycin M1 was created by feeding virginiamycin M1 into a culture of recombinant Streptomyces venezuelae. Its chemical structure was spectroscopically elucidated, and this streptogramin A analogue showed twofold higher antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA) compared with its parent molecule virginiamycin M1. Docking studies using the model of streptogramin A acetyltransferase (VatA) suggested that the newly generated analogue binds tighter with overall lower free energy compared with the parent molecule virginiamycin M1. This hypothesis was validated experimentally through the improvement of efficacy of the new analogue against MRSA strains. The biotransformation approach presented herein could have a broad application in the production of reduced macrocyclic molecules.
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Affiliation(s)
- N H Hoang
- Department of Pharmaceutical Engineering, SunMoon University, Asan, Korea
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12
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Anand S, Mohanty D. Computational Methods for Identification of Novel Secondary Metabolite Biosynthetic Pathways by Genome Analysis. Bioinformatics 2013. [DOI: 10.4018/978-1-4666-3604-0.ch086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Secondary metabolites belonging to polyketide and nonribosomal peptide families constitute a major class of natural products with diverse biological functions and a variety of pharmaceutically important properties. Experimental studies have shown that the biosynthetic machinery for polyketide and nonribosomal peptides involves multi-functional megasynthases like Polyketide Synthases (PKSs) and nonribosomal peptide synthetases (NRPSs) which utilize a thiotemplate mechanism similar to that for fatty acid biosynthesis. Availability of complete genome sequences for an increasing number of microbial organisms has provided opportunities for using in silico genome mining to decipher the secondary metabolite natural product repertoire encoded by these organisms. Therefore, in recent years there have been major advances in development of computational methods which can analyze genome sequences to identify genes involved in secondary metabolite biosynthesis and help in deciphering the putative chemical structures of their biosynthetic products based on analysis of the sequence and structural features of the proteins encoded by these genes. These computational methods for deciphering the secondary metabolite biosynthetic code essentially involve identification of various catalytic domains present in this PKS/NRPS family of enzymes; a prediction of various reactions in these enzymatic domains and their substrate specificities and also precise identification of the order in which these domains would catalyze various biosynthetic steps. Structural bioinformatics analysis of known secondary metabolite biosynthetic clusters has helped in formulation of predictive rules for deciphering domain organization, substrate specificity, and order of substrate channeling. In this chapter, the progress in development of various computational methods is discussed by different research groups, and specifically, the utility in identification of novel metabolites by genome mining and rational design of natural product analogs by biosynthetic engineering studies.
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13
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Mohanty D, Sankaranarayanan R, Gokhale RS. Fatty acyl-AMP ligases and polyketide synthases are unique enzymes of lipid biosynthetic machinery in Mycobacterium tuberculosis. Tuberculosis (Edinb) 2011; 91:448-55. [PMID: 21601529 DOI: 10.1016/j.tube.2011.04.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 04/21/2011] [Indexed: 12/24/2022]
Abstract
The cell envelope of Mycobacterium tuberculosis (Mtb) possesses a repertoire of unusual lipids that are believed to play an important role in pathogenesis. In this review, we specifically focus on computational, biochemical and structural studies in lipid biosynthesis that have established functional role of polyketide synthases (PKSs) and fatty acyl-AMP ligases (FAALs). Mechanistic and structural studies with FAALs suggest that this group of proteins may have evolved from omnipresent fatty acyl-CoA ligases (FACLs). FAALs activate fatty acids as acyl-adenylates and transfer them on to the PKSs which then produce unusual acyl chains that are the components of mycobacterial lipids. FAALs are a newly discovered family of enzymes; whereas involvement of PKSs in lipid metabolism was not known prior to their discovery in Mtb. Since Mtb genome contains multiple homologs of FAALs and PKSs and owing to the conserved reaction mechanism and overlapping substrate specificity; there is tempting opportunity to develop 'systemic drugs' against these enzymes as anti-tuberculosis agents.
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Affiliation(s)
- Debasisa Mohanty
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110 067, India.
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14
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Banerjee R, Vats P, Dahale S, Kasibhatla SM, Joshi R. Comparative genomics of cell envelope components in mycobacteria. PLoS One 2011; 6:e19280. [PMID: 21573108 PMCID: PMC3089613 DOI: 10.1371/journal.pone.0019280] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 03/25/2011] [Indexed: 12/26/2022] Open
Abstract
Mycobacterial cell envelope components have been a major focus of research due to their unique features that confer intrinsic resistance to antibiotics and chemicals apart from serving as a low-permeability barrier. The complex lipids secreted by Mycobacteria are known to evoke/repress host-immune response and thus contribute to its pathogenicity. This study focuses on the comparative genomics of the biosynthetic machinery of cell wall components across 21-mycobacterial genomes available in GenBank release 179.0. An insight into survival in varied environments could be attributed to its variation in the biosynthetic machinery. Gene-specific motifs like 'DLLAQPTPAW' of ufaA1 gene, novel functional linkages such as involvement of Rv0227c in mycolate biosynthesis; Rv2613c in LAM biosynthesis and Rv1209 in arabinogalactan peptidoglycan biosynthesis were detected in this study. These predictions correlate well with the available mutant and coexpression data from TBDB. It also helped to arrive at a minimal functional gene set for these biosynthetic pathways that complements findings using TraSH.
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Affiliation(s)
- Ruma Banerjee
- Bioinformatics Group, Centre for Development of Advanced Computing, Pune University Campus, Pune, Maharashtra, India
| | - Pankaj Vats
- Bioinformatics Group, Centre for Development of Advanced Computing, Pune University Campus, Pune, Maharashtra, India
| | - Sonal Dahale
- Bioinformatics Group, Centre for Development of Advanced Computing, Pune University Campus, Pune, Maharashtra, India
| | - Sunitha Manjari Kasibhatla
- Bioinformatics Group, Centre for Development of Advanced Computing, Pune University Campus, Pune, Maharashtra, India
| | - Rajendra Joshi
- Bioinformatics Group, Centre for Development of Advanced Computing, Pune University Campus, Pune, Maharashtra, India
- * E-mail:
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15
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Generation of reduced macrolide analogs by regio-specific biotransformation. J Antibiot (Tokyo) 2010; 64:155-7. [DOI: 10.1038/ja.2010.143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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16
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Anand S, Prasad MVR, Yadav G, Kumar N, Shehara J, Ansari MZ, Mohanty D. SBSPKS: structure based sequence analysis of polyketide synthases. Nucleic Acids Res 2010; 38:W487-96. [PMID: 20444870 PMCID: PMC2896141 DOI: 10.1093/nar/gkq340] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Polyketide synthases (PKSs) catalyze biosynthesis of a diverse family of pharmaceutically important secondary metabolites. Bioinformatics analysis of sequence and structural features of PKS proteins plays a crucial role in discovery of new natural products by genome mining, as well as in design of novel secondary metabolites by biosynthetic engineering. The availability of the crystal structures of various PKS catalytic and docking domains, and mammalian fatty acid synthase module prompted us to develop SBSPKS software which consists of three major components. Model_3D_PKS can be used for modeling, visualization and analysis of 3D structure of individual PKS catalytic domains, dimeric structures for complete PKS modules and prediction of substrate specificity. Dock_Dom_Anal identifies the key interacting residue pairs in inter-subunit interfaces based on alignment of inter-polypeptide linker sequences to the docking domain structure. In case of modular PKS with multiple open reading frames (ORFs), it can predict the cognate order of substrate channeling based on combinatorial evaluation of all possible interface contacts. NRPS–PKS provides user friendly tools for identifying various catalytic domains in the sequence of a Type I PKS protein and comparing them with experimentally characterized PKS/NRPS clusters cataloged in the backend databases of SBSPKS. SBSPKS is available at http://www.nii.ac.in/sbspks.html.
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Affiliation(s)
- Swadha Anand
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
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17
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de Souza GA, Fortuin S, Aguilar D, Pando RH, McEvoy CRE, van Helden PD, Koehler CJ, Thiede B, Warren RM, Wiker HG. Using a label-free proteomics method to identify differentially abundant proteins in closely related hypo- and hypervirulent clinical Mycobacterium tuberculosis Beijing isolates. Mol Cell Proteomics 2010; 9:2414-23. [PMID: 20190197 PMCID: PMC2984234 DOI: 10.1074/mcp.m900422-mcp200] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Although the genome of the Mycobacterium tuberculosis H37Rv laboratory strain has been available for over 10 years, it is only recently that genomic information from clinical isolates has been used to generate the hypothesis of virulence differences between different strains. In addition, the relationship between strains displaying differing virulence in an epidemiological setting and their behavior in animal models has received little attention. The potential causes for variation in virulence between strains, as determined by differential protein expression, have similarly been a neglected area of investigation. In this study, we used a label-free quantitative proteomics approach to estimate differences in protein abundance between two closely related Beijing genotypes that have been shown to be hyper- and hypovirulent on the basis of both epidemiological and mouse model studies. We were able to identify a total of 1668 proteins from both samples, and protein abundance calculations revealed that 48 proteins were over-represented in the hypovirulent isolate, whereas 53 were over-represented in the hypervirulent. Functional classification of these results shows that molecules of cell wall organization and DNA transcription regulatory proteins may have a critical influence in defining the level of virulence. The reduction in the presence of ESAT-6, other Esx-like proteins, and FbpD (MPT51) in the hypervirulent strain indicates that changes in the repertoire of highly immunogenic proteins can be a defensive process undertaken by the virulent cell. In addition, most of the previously well characterized gene targets related to virulence were found to be similarly expressed in our model. Our data support the use of proteomics as a complementary tool for genomic comparisons to understand the biology of M. tuberculosis virulence.
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Affiliation(s)
- Gustavo A de Souza
- Section for Microbiology and Immunology, The Gade Institute, University of Bergen, Bergen, Norway
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18
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Murry JP, Pandey AK, Sassetti CM, Rubin EJ. Phthiocerol dimycocerosate transport is required for resisting interferon-gamma-independent immunity. J Infect Dis 2009; 200:774-82. [PMID: 19622047 DOI: 10.1086/605128] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Nitric oxide (NO), which is an important component of immunity to Mycobacterium tuberculosis, has both cytotoxic and immune regulatory functions. We examined the way that this molecule interacts with M. tuberculosis in vivo by screening for bacterial mutations that alter growth in mice that are unable to produce inducible NO synthase (iNOS), the dominant source of NO during infection. We found that very few bacterial genes appeared to be specifically required for resistance to NO in vivo. Instead, mutations in several virulence factors caused greater attenuation in the absence of iNOS. Among these were mutants incapable of transporting the lipid phthiocerol dimycocerosate (PDIM). Although PDIM has been implicated in NO defense, this result indicates that PDIM has other roles during infection. We additionally found that PDIM transport is required for virulence in mice lacking interferon-gamma . Thus, PDIM is important for resisting an interferon-gamma-independent mechanism of immunity.
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Affiliation(s)
- Jeffrey P Murry
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA
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19
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Guenin-Macé L, Siméone R, Demangel C. Lipids of Pathogenic Mycobacteria: Contributions to Virulence and Host Immune Suppression. Transbound Emerg Dis 2009; 56:255-68. [DOI: 10.1111/j.1865-1682.2009.01072.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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20
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Carboxylation mechanism and stereochemistry of crotonyl-CoA carboxylase/reductase, a carboxylating enoyl-thioester reductase. Proc Natl Acad Sci U S A 2009; 106:8871-6. [PMID: 19458256 DOI: 10.1073/pnas.0903939106] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Chemo- and stereoselective reductions are important reactions in chemistry and biology, and reductases from biological sources are increasingly applied in organic synthesis. In contrast, carboxylases are used only sporadically. We recently described crotonyl-CoA carboxylase/reductase, which catalyzes the reduction of (E)-crotonyl-CoA to butyryl-CoA but also the reductive carboxylation of (E)-crotonyl-CoA to ethylmalonyl-CoA. In this study, the complete stereochemical course of both reactions was investigated in detail. The pro-(4R) hydrogen of NADPH is transferred in both reactions to the re face of the C3 position of crotonyl-CoA. In the course of the carboxylation reaction, carbon dioxide is incorporated in anti fashion at the C2 atom of crotonyl-CoA. For the reduction reaction that yields butyryl-CoA, a solvent proton is added in anti fashion instead of the CO(2). Amino acid sequence analysis showed that crotonyl-CoA carboxylase/reductase is a member of the medium-chain dehydrogenase/reductase superfamily and shares the same phylogenetic origin. The stereospecificity of the hydride transfer from NAD(P)H within this superfamily is highly conserved, although the substrates and reduction reactions catalyzed by its individual representatives differ quite considerably. Our findings led to a reassessment of the stereospecificity of enoyl(-thioester) reductases and related enzymes with respect to their amino acid sequence, revealing a general pattern of stereospecificity that allows the prediction of the stereochemistry of the hydride transfer for enoyl reductases of unknown specificity. Further considerations on the reaction mechanism indicated that crotonyl-CoA carboxylase/reductase may have evolved from enoyl-CoA reductases. This may be useful for protein engineering of enoyl reductases and their application in biocatalysis.
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Yadav G, Gokhale RS, Mohanty D. Towards prediction of metabolic products of polyketide synthases: an in silico analysis. PLoS Comput Biol 2009; 5:e1000351. [PMID: 19360130 PMCID: PMC2661021 DOI: 10.1371/journal.pcbi.1000351] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2008] [Accepted: 03/09/2009] [Indexed: 12/18/2022] Open
Abstract
Sequence data arising from an increasing number of partial and complete genome projects is revealing the presence of the polyketide synthase (PKS) family of genes not only in microbes and fungi but also in plants and other eukaryotes. PKSs are huge multifunctional megasynthases that use a variety of biosynthetic paradigms to generate enormously diverse arrays of polyketide products that posses several pharmaceutically important properties. The remarkable conservation of these gene clusters across organisms offers abundant scope for obtaining novel insights into PKS biosynthetic code by computational analysis. We have carried out a comprehensive in silico analysis of modular and iterative gene clusters to test whether chemical structures of the secondary metabolites can be predicted from PKS protein sequences. Here, we report the success of our method and demonstrate the feasibility of deciphering the putative metabolic products of uncharacterized PKS clusters found in newly sequenced genomes. Profile Hidden Markov Model analysis has revealed distinct sequence features that can distinguish modular PKS proteins from their iterative counterparts. For iterative PKS proteins, structural models of iterative ketosynthase (KS) domains have revealed novel correlations between the size of the polyketide products and volume of the active site pocket. Furthermore, we have identified key residues in the substrate binding pocket that control the number of chain extensions in iterative PKSs. For modular PKS proteins, we describe for the first time an automated method based on crucial intermolecular contacts that can distinguish the correct biosynthetic order of substrate channeling from a large number of non-cognate combinatorial possibilities. Taken together, our in silico analysis provides valuable clues for formulating rules for predicting polyketide products of iterative as well as modular PKS clusters. These results have promising potential for discovery of novel natural products by genome mining and rational design of novel natural products.
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22
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Gordon SV, Bottai D, Simeone R, Stinear TP, Brosch R. Pathogenicity in the tubercle bacillus: molecular and evolutionary determinants. Bioessays 2009; 31:378-88. [DOI: 10.1002/bies.200800191] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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23
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Vissa VD, Sakamuri RM, Li W, Brennan PJ. Defining mycobacteria: Shared and specific genome features for different lifestyles. Indian J Microbiol 2009; 49:11-47. [PMID: 23100749 DOI: 10.1007/s12088-009-0006-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2007] [Accepted: 08/16/2008] [Indexed: 11/28/2022] Open
Abstract
During the last decade, the combination of rapid whole genome sequencing capabilities, application of genetic and computational tools, and establishment of model systems for the study of a range of species for a spectrum of biological questions has enhanced our cumulative knowledge of mycobacteria in terms of their growth properties and requirements. The adaption of the corynebacterial surrogate system has simplified the study of cell wall biosynthetic machinery common to actinobacteria. Comparative genomics supported by experimentation reveals that superimposed on a common core of 'mycobacterial' gene set, pathogenic mycobacteria are endowed with multiple copies of several protein families that encode novel secretion and transport systems such as mce and esx; immunomodulators named PE/PPE proteins, and polyketide synthases for synthesis of complex lipids. The precise timing of expression, engagement and interactions involving one or more of these redundant proteins in their host environments likely play a role in the definition and differentiation of species and their disease phenotypes. Besides these, only a few species specific 'virulence' factors i.e., macromolecules have been discovered. Other subtleties may also arise from modifications of shared macromolecules. In contrast, to cope with the broad and changing growth conditions, their saprophytic relatives have larger genomes, in which the excess coding capacity is dedicated to transcriptional regulators, transporters for nutrients and toxic metabolites, biosynthesis of secondary metabolites and catabolic pathways. In this review, we present a sampling of the tools and techniques that are being implemented to tease apart aspects of physiology, phylogeny, ecology and pathology and illustrate the dominant genomic characteristics of representative species. The investigation of clinical isolates, natural disease states and discovery of new diagnostics, vaccines and drugs for existing and emerging mycobacterial diseases, particularly for multidrug resistant strains are the challenges in the coming decades.
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Affiliation(s)
- Varalakshmi D Vissa
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO-80523-1628 USA
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Chopra T, Gokhale RS. Chapter 12 Polyketide Versatility in the Biosynthesis of Complex Mycobacterial Cell Wall Lipids. Methods Enzymol 2009; 459:259-94. [DOI: 10.1016/s0076-6879(09)04612-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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25
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Kwan DH, Sun Y, Schulz F, Hong H, Popovic B, Sim-Stark JC, Haydock SF, Leadlay PF. Prediction and Manipulation of the Stereochemistry of Enoylreduction in Modular Polyketide Synthases. ACTA ACUST UNITED AC 2008; 15:1231-40. [DOI: 10.1016/j.chembiol.2008.09.012] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Revised: 09/11/2008] [Accepted: 09/17/2008] [Indexed: 10/21/2022]
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26
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Halo LM, Marshall JW, Yakasai AA, Song Z, Butts CP, Crump MP, Heneghan M, Bailey AM, Simpson TJ, Lazarus CM, Cox RJ. Authentic Heterologous Expression of the Tenellin Iterative Polyketide Synthase Nonribosomal Peptide Synthetase Requires Coexpression with an Enoyl Reductase. Chembiochem 2008; 9:585-94. [PMID: 18266306 DOI: 10.1002/cbic.200700390] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Laura M Halo
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
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Park JW, Oh HS, Jung WS, Park SR, Han AR, Ban YH, Kim EJ, Kang HY, Yoon YJ. Exploiting the natural metabolic diversity of Streptomyces venezuelae to generate unusual reduced macrolides. Chem Commun (Camb) 2008:5782-4. [DOI: 10.1039/b814603a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ferreras JA, Stirrett KL, Lu X, Ryu JS, Soll CE, Tan DS, Quadri LEN. Mycobacterial phenolic glycolipid virulence factor biosynthesis: mechanism and small-molecule inhibition of polyketide chain initiation. ACTA ACUST UNITED AC 2007; 15:51-61. [PMID: 18158259 DOI: 10.1016/j.chembiol.2007.11.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Revised: 11/24/2007] [Accepted: 11/29/2007] [Indexed: 10/22/2022]
Abstract
Phenolic glycolipids (PGLs) are polyketide-derived virulence factors produced by Mycobacterium tuberculosis, M. leprae, and other mycobacterial pathogens. We have combined bioinformatic, genetic, biochemical, and chemical biology approaches to illuminate the mechanism of chain initiation required for assembly of the p-hydroxyphenyl-polyketide moiety of PGLs. Our studies have led to the identification of a stand-alone, didomain initiation module, FadD22, comprised of a p-hydroxybenzoic acid adenylation domain and an aroyl carrier protein domain. FadD22 forms an acyl-S-enzyme covalent intermediate in the p-hydroxyphenyl-polyketide chain assembly line. We also used this information to develop a small-molecule inhibitor of PGL biosynthesis. Overall, these studies provide insights into the biosynthesis of an important group of small-molecule mycobacterial virulence factors and support the feasibility of targeting PGL biosynthesis to develop new drugs to treat mycobacterial infections.
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Affiliation(s)
- Julian A Ferreras
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
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Gokhale RS, Sankaranarayanan R, Mohanty D. Versatility of polyketide synthases in generating metabolic diversity. Curr Opin Struct Biol 2007; 17:736-43. [PMID: 17935970 DOI: 10.1016/j.sbi.2007.08.021] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Revised: 08/20/2007] [Accepted: 08/24/2007] [Indexed: 11/25/2022]
Abstract
Polyketide synthases (PKSs) form a large family of multifunctional proteins involved in the biosynthesis of diverse classes of natural products. Architecturally at least three different types of PKSs have been discovered in the microbial world and recent years have revealed tremendous versatility of PKSs, both in terms of their structural and functional organization and in their ability to produce compounds other than typical secondary metabolites. Mycobacterium tuberculosis exploits polyketide biosynthetic enzymes to synthesize complex lipids, many of which are essential for its survival. The functional significance of the large repertoire of PKSs in Dictyostelium discoideum, perhaps in producing developmental regulating factors, is emerging. Recently determined structures of fatty acid synthases (FASs) and PKSs now provide an opportunity to delineate the mechanistic and structural basis of polyketide biosynthetic machinery.
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Affiliation(s)
- Rajesh S Gokhale
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India.
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