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Sodani M, Misra CS, Nigam G, Fatima Z, Kulkarni S, Rath D. MSMEG_0311 is a conserved essential polar protein involved in mycobacterium cell wall metabolism. Int J Biol Macromol 2024; 260:129583. [PMID: 38242409 DOI: 10.1016/j.ijbiomac.2024.129583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 01/16/2024] [Accepted: 01/16/2024] [Indexed: 01/21/2024]
Abstract
Cell wall synthesis and cell division are two closely linked pathways in a bacterial cell which distinctly influence the growth and survival of a bacterium. This requires an appreciable coordination between the two processes, more so, in case of mycobacteria with an intricate multi-layered cell wall structure. In this study, we investigated a conserved gene cluster using CRISPR-Cas12 based gene silencing technology to show that knockdown of most of the genes in this cluster leads to growth defects. Investigating conserved genes is important as they likely perform vital cellular functions and the functional insights on such genes can be extended to other mycobacterial species. We characterised one of the genes in the locus, MSMEG_0311. The repression of this gene not only imparts severe growth defect but also changes colony morphology. We demonstrate that the protein preferentially localises to the polar region and investigate its influence on the polar growth of the bacillus. A combination of permeability and drug susceptibility assay strongly suggests a cell wall associated function of this gene which is also corroborated by transcriptomic analysis of the knockdown where a number of cell wall associated genes, particularly iniA and sigF regulon get altered. Considering the gene is highly conserved across mycobacterial species and appears to be essential for growth, it may serve as a potential drug target.
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Affiliation(s)
- Megha Sodani
- Radiation Medicine Centre, Medical Group, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra, India; Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, Maharashtra, India
| | - Chitra S Misra
- Applied Genomics Section, Bio-Science Group, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra, India
| | - Gaurav Nigam
- Amity Institute of Biotechnology, Amity University Haryana, Gurugram, India
| | - Zeeshan Fatima
- Amity Institute of Biotechnology, Amity University Haryana, Gurugram, India; Department of Laboratory Medicine, Faculty of Applied Medical Sciences, University of Bisha, Bisha, Saudi Arabia
| | - Savita Kulkarni
- Radiation Medicine Centre, Medical Group, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra, India; Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, Maharashtra, India.
| | - Devashish Rath
- Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, Maharashtra, India; Applied Genomics Section, Bio-Science Group, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra, India.
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2
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Lee SY, Marando VM, Smelyansky SR, Kim DE, Calabretta PJ, Warner TC, Bryson BD, Kiessling LL. Selective Glycan Labeling of Mannose-Containing Glycolipids in Mycobacteria. J Am Chem Soc 2024; 146:377-385. [PMID: 38112296 PMCID: PMC10914408 DOI: 10.1021/jacs.3c09495] [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] [Indexed: 12/21/2023]
Abstract
Mycobacterium tuberculosis (Mtb) is one of history's most successful human pathogens. By subverting typical immune responses, Mtb can persist within a host until conditions become favorable for growth and proliferation. Virulence factors that enable mycobacteria to modulate host immune systems include a suite of mannose-containing glycolipids: phosphatidylinositol mannosides, lipomannan, and lipoarabinomannan (LAM). Despite their importance, tools for their covalent capture, modification, and imaging are limited. Here, we describe a chemical biology strategy to detect and visualize these glycans. Our approach, biosynthetic incorporation, is to synthesize a lipid-glycan precursor that can be incorporated at a late-stage step in glycolipid biosynthesis. We previously demonstrated selective mycobacterial arabinan modification by biosynthetic incorporation using an exogenous donor. This report reveals that biosynthetic labeling is general and selective: it allows for cell surface mannose-containing glycolipid modification without nonspecific labeling of mannosylated glycoproteins. Specifically, we employed azido-(Z,Z)-farnesyl phosphoryl-β-d-mannose probes and took advantage of the strain-promoted azide-alkyne cycloaddition to label and directly visualize the localization and dynamics of mycobacterial mannose-containing glycolipids. Our studies highlight the generality and utility of biosynthetic incorporation as the probe structure directs the selective labeling of distinct glycans. The disclosed agents allowed for direct tracking of the target immunomodulatory glycolipid dynamics in cellulo. We anticipate that these probes will facilitate investigating the diverse biological roles of these glycans.
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Affiliation(s)
- So Young Lee
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Victoria M. Marando
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Stephanie R. Smelyansky
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Daria E. Kim
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Phillip J. Calabretta
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, University of Wisconsin Madison, Madison, Wisconsin 53706, United States
| | - Theodore C. Warner
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Bryan D. Bryson
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts 02139, USA
| | - Laura L. Kiessling
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, University of Wisconsin Madison, Madison, Wisconsin 53706, United States
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts 02139, USA
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3
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Zhang L, Rao Z. Structural biology and inhibition of the Mtb cell wall glycoconjugates biosynthesis on the membrane. Curr Opin Struct Biol 2023; 82:102670. [PMID: 37542906 DOI: 10.1016/j.sbi.2023.102670] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 06/08/2023] [Accepted: 07/10/2023] [Indexed: 08/07/2023]
Abstract
Glycoconjugates are the dominant components of the Mycobacterium tuberculosis cell wall. These glycoconjugates are essential for the viability of Mtb and attribute to drug resistance and virulence during infection. The assembly and maturation of the cell wall largely relies on the Mtb plasma membrane. A significant number of membrane-bound glycosyltransferases (GTs) and transporters play pivotal roles in forming the complex glycoconjugates and are targeted by the first-line anti-TB drug and potent drug candidates. Here we summarize the latest structural biology of mycobacterial GTs and transporters, and describe the modes of action of drug and drug candidates that are of substantial clinical value in anti-TB chemotherapeutics.
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Affiliation(s)
- Lu Zhang
- Shanghai Institute for Advanced Immunochemical Studies, School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.
| | - Zihe Rao
- Laboratory of Structural Biology, Tsinghua University, Beijing 100084, China.
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4
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Patel O, Brammananth R, Dai W, Panjikar S, Coppel RL, Lucet IS, Crellin PK. Crystal structure of the putative cell-wall lipoglycan biosynthesis protein LmcA from Mycobacterium smegmatis. Acta Crystallogr D Struct Biol 2022; 78:494-508. [PMID: 35362472 PMCID: PMC8972800 DOI: 10.1107/s2059798322001772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 02/16/2022] [Indexed: 11/17/2022] Open
Abstract
The first crystal structure of the putative cell-wall biosynthesis protein LmcA from Mycobacterium smegmatis is reported at 1.8 Å resolution. The structure revealed an elongated β-barrel fold enclosing two distinct cavities, indicating a possible lipid-binding function in lipomannan/lipoarabinomannan biosynthesis. The bacterial genus Mycobacterium includes important pathogens, most notably M. tuberculosis, which infects one-quarter of the entire human population, resulting in around 1.4 million deaths from tuberculosis each year. Mycobacteria, and the closely related corynebacteria, synthesize a class of abundant glycolipids, the phosphatidyl-myo-inositol mannosides (PIMs). PIMs serve as membrane anchors for hyperglycosylated species, lipomannan (LM) and lipoarabinomannan (LAM), which are surface-exposed and modulate the host immune response. Previously, in studies using the model species Corynebacterium glutamicum, NCgl2760 was identified as a novel membrane protein that is required for the synthesis of full-length LM and LAM. Here, the first crystal structure of its ortholog in Mycobacterium smegmatis, MSMEG_0317, is reported at 1.8 Å resolution. The structure revealed an elongated β-barrel fold enclosing two distinct cavities and one α-helix extending away from the β-barrel core, resembling a ‘cone with a flake’ arrangement. Through xenon derivatization and structural comparison with AlphaFold2-derived predictions of the M. tuberculosis homolog Rv0227c, structural elements were identified that may undergo conformational changes to switch from ‘closed’ to ‘open’ conformations, allowing cavity access. An AlphaFold2-derived NCgl2760 model predicted a smaller β-barrel core with an enclosed central cavity, suggesting that all three proteins, which were collectively termed LmcA, may have a common mechanism of ligand binding through these cavities. These findings provide new structural insights into the biosynthetic pathway for a family of surface lipoglycans with important roles in mycobacterial pathogenesis.
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5
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Structural basis for safe and efficient energy conversion in a respiratory supercomplex. Nat Commun 2022; 13:545. [PMID: 35087070 PMCID: PMC8795186 DOI: 10.1038/s41467-022-28179-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 01/10/2022] [Indexed: 12/19/2022] Open
Abstract
Proton-translocating respiratory complexes assemble into supercomplexes that are proposed to increase the efficiency of energy conversion and limit the production of harmful reactive oxygen species during aerobic cellular respiration. Cytochrome bc complexes and cytochrome aa3 oxidases are major drivers of the proton motive force that fuels ATP generation via respiration, but how wasteful electron- and proton transfer is controlled to enhance safety and efficiency in the context of supercomplexes is not known. Here, we address this question with the 2.8 Å resolution cryo-EM structure of the cytochrome bcc-aa3 (III2-IV2) supercomplex from the actinobacterium Corynebacterium glutamicum. Menaquinone, substrate mimics, lycopene, an unexpected Qc site, dioxygen, proton transfer routes, and conformational states of key protonable residues are resolved. Our results show how safe and efficient energy conversion is achieved in a respiratory supercomplex through controlled electron and proton transfer. The structure may guide the rational design of drugs against actinobacteria that cause diphtheria and tuberculosis. Aerobic energy metabolism is driven by proton-pumping respiratory supercomplexes. The study reports the structural basis for energy conversion in such supercomplex. It may aid metabolic engineering and drug design against diphtheria and tuberculosis.
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6
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Gupta KR, Gwin CM, Rahlwes KC, Biegas KJ, Wang C, Park JH, Liu J, Swarts BM, Morita YS, Rego EH. An essential periplasmic protein coordinates lipid trafficking and is required for asymmetric polar growth in mycobacteria. eLife 2022; 11:80395. [PMID: 36346214 PMCID: PMC9678360 DOI: 10.7554/elife.80395] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 11/07/2022] [Indexed: 11/10/2022] Open
Abstract
Mycobacteria, including the human pathogen Mycobacterium tuberculosis, grow by inserting new cell wall material at their poles. This process and that of division are asymmetric, producing a phenotypically heterogeneous population of cells that respond non-uniformly to stress (Aldridge et al., 2012; Rego et al., 2017). Surprisingly, deletion of a single gene - lamA - leads to more symmetry, and to a population of cells that is more uniformly killed by antibiotics (Rego et al., 2017). How does LamA create asymmetry? Here, using a combination of quantitative time-lapse imaging, bacterial genetics, and lipid profiling, we find that LamA recruits essential proteins involved in cell wall synthesis to one side of the cell - the old pole. One of these proteins, MSMEG_0317, here renamed PgfA, was of unknown function. We show that PgfA is a periplasmic protein that interacts with MmpL3, an essential transporter that flips mycolic acids in the form of trehalose monomycolate (TMM), across the plasma membrane. PgfA interacts with a TMM analog suggesting a direct role in TMM transport. Yet our data point to a broader function as well, as cells with altered PgfA levels have differences in the abundance of other lipids and are differentially reliant on those lipids for survival. Overexpression of PgfA, but not MmpL3, restores growth at the old poles in cells missing lamA. Together, our results suggest that PgfA is a key determinant of polar growth and cell envelope composition in mycobacteria, and that the LamA-mediated recruitment of this protein to one side of the cell is a required step in the establishment of cellular asymmetry.
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Affiliation(s)
- Kuldeepkumar R Gupta
- Department of Microbial Pathogenesis, Yale University School of MedicineNew HavenUnited States
| | - Celena M Gwin
- Department of Microbial Pathogenesis, Yale University School of MedicineNew HavenUnited States
| | - Kathryn C Rahlwes
- Department of Microbiology, University of MassachusettsAmherstUnited States
| | - Kyle J Biegas
- Department of Chemistry and Biochemistry, Central Michigan UniversityMount PleasantUnited States,Biochemistry, Cell, and Molecular Biology Program, Central Michigan UniversityMount PleasantUnited States
| | - Chunyan Wang
- Department of Microbial Pathogenesis, Yale University School of MedicineNew HavenUnited States,Microbial Sciences Institute, Yale UniversityWest HavenUnited States
| | - Jin Ho Park
- Department of Microbial Pathogenesis, Yale University School of MedicineNew HavenUnited States
| | - Jun Liu
- Department of Microbial Pathogenesis, Yale University School of MedicineNew HavenUnited States,Microbial Sciences Institute, Yale UniversityWest HavenUnited States
| | - Benjamin M Swarts
- Department of Chemistry and Biochemistry, Central Michigan UniversityMount PleasantUnited States,Biochemistry, Cell, and Molecular Biology Program, Central Michigan UniversityMount PleasantUnited States
| | - Yasu S Morita
- Department of Microbiology, University of MassachusettsAmherstUnited States
| | - E Hesper Rego
- Department of Microbial Pathogenesis, Yale University School of MedicineNew HavenUnited States
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7
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MmpA, a Conserved Membrane Protein Required for Efficient Surface Transport of Trehalose Lipids in Corynebacterineae. Biomolecules 2021; 11:biom11121760. [PMID: 34944401 PMCID: PMC8698533 DOI: 10.3390/biom11121760] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 12/23/2022] Open
Abstract
Cell walls of bacteria of the genera Mycobacterium and Corynebacterium contain high levels of (coryno)mycolic acids. These very long chain fatty acids are synthesized on the cytoplasmic leaflet of the inner membrane (IM) prior to conjugation to the disaccharide, trehalose, and transport to the periplasm. Recent studies on Corynebacterium glutamicum have shown that acetylation of trehalose monohydroxycorynomycolate (hTMCM) promotes its transport across the inner membrane. Acetylation is mediated by the membrane acetyltransferase, TmaT, and is dependent on the presence of a putative methyltransferase, MtrP. Here, we identify a third protein that is required for the acetylation and membrane transport of hTMCM. Deletion of the C. glutamicum gene NCgl2761 (Rv0226c in Mycobacterium tuberculosis) abolished synthesis of acetylated hTMCM (AcTMCM), resulting in an accumulation of hTMCM in the inner membrane and reduced synthesis of trehalose dihydroxycorynomycolate (h2TDCM), a major outer membrane glycolipid. Complementation with the NCgl2761 gene, designated here as mmpA, restored the hTMCM:h2TDCM ratio. Comprehensive lipidomic analysis of the ΔtmaT, ΔmtrP and ΔmmpA mutants revealed strikingly similar global changes in overall membrane lipid composition. Our findings suggest that the acetylation and membrane transport of hTMCM is regulated by multiple proteins: MmpA, MtrP and TmaT, and that defects in this process lead to global, potentially compensatory changes in the composition of inner and outer membranes.
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8
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Flores J, Cancino JC, Chavez-Galan L. Lipoarabinomannan as a Point-of-Care Assay for Diagnosis of Tuberculosis: How Far Are We to Use It? Front Microbiol 2021; 12:638047. [PMID: 33935997 PMCID: PMC8081860 DOI: 10.3389/fmicb.2021.638047] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 03/22/2021] [Indexed: 12/13/2022] Open
Abstract
Tuberculosis (TB) is still a severe public health problem; the current diagnostic tests have limitations that delay treatment onset. Lipoarabinomannan (LAM) is a glycolipid that is a component of the cell wall of the bacillus Mycobacterium tuberculosis, the etiologic agent of TB. This glycolipid is excreted as a soluble form in urine. The World Health Organization has established that the design of new TB diagnostic methods is one of the priorities within the EndTB Strategy. LAM has been suggested as a biomarker to develop diagnostic tests based on its identification in urine, and it is one of the most prominent candidates to develop point-of-care diagnostic test because urine samples can be easily collected. Moreover, LAM can regulate the immune response in the host and can be found in the serum of TB patients, where it probably affects a wide variety of host cell populations, consequently influencing the quality of both innate and adaptive immune responses during TB infection. Here, we revised the evidence that supports that LAM could be used as a tool for the development of new point-of-care tests for TB diagnosis, and we discussed the mechanisms that could contribute to the low sensitivity of diagnostic testing.
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Affiliation(s)
- Julio Flores
- Laboratory of Integrative Immunology, Instituto Nacional de Enfermedades Respiratorias Ismael Cosio Villegas, Mexico City, Mexico.,Laboratory of Immunomicrobiology, Department of Microbiology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Juan Carlos Cancino
- Laboratory of Immunomicrobiology, Department of Microbiology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Leslie Chavez-Galan
- Laboratory of Integrative Immunology, Instituto Nacional de Enfermedades Respiratorias Ismael Cosio Villegas, Mexico City, Mexico
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9
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de Wet TJ, Winkler KR, Mhlanga M, Mizrahi V, Warner DF. Arrayed CRISPRi and quantitative imaging describe the morphotypic landscape of essential mycobacterial genes. eLife 2020; 9:e60083. [PMID: 33155979 PMCID: PMC7647400 DOI: 10.7554/elife.60083] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 10/03/2020] [Indexed: 12/11/2022] Open
Abstract
Mycobacterium tuberculosis possesses a large number of genes of unknown or predicted function, undermining fundamental understanding of pathogenicity and drug susceptibility. To address this challenge, we developed a high-throughput functional genomics approach combining inducible CRISPR-interference and image-based analyses of morphological features and sub-cellular chromosomal localizations in the related non-pathogen, M. smegmatis. Applying automated imaging and analysis to 263 essential gene knockdown mutants in an arrayed library, we derive robust, quantitative descriptions of bacillary morphologies consequent on gene silencing. Leveraging statistical-learning, we demonstrate that functionally related genes cluster by morphotypic similarity and that this information can be used to inform investigations of gene function. Exploiting this observation, we infer the existence of a mycobacterial restriction-modification system, and identify filamentation as a defining mycobacterial response to histidine starvation. Our results support the application of large-scale image-based analyses for mycobacterial functional genomics, simultaneously establishing the utility of this approach for drug mechanism-of-action studies.
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Affiliation(s)
- Timothy J de Wet
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Kristy R Winkler
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Musa Mhlanga
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Department of Integrative Biomedical Sciences, University of Cape TownCape TownSouth Africa
| | - Valerie Mizrahi
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Wellcome Centre for Infectious Diseases Research in Africa, University of Cape TownCape TownSouth Africa
| | - Digby F Warner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Wellcome Centre for Infectious Diseases Research in Africa, University of Cape TownCape TownSouth Africa
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10
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Grinter R, Ney B, Brammananth R, Barlow CK, Cordero PRF, Gillett DL, Izoré T, Cryle MJ, Harold LK, Cook GM, Taiaroa G, Williamson DA, Warden AC, Oakeshott JG, Taylor MC, Crellin PK, Jackson CJ, Schittenhelm RB, Coppel RL, Greening C. Cellular and Structural Basis of Synthesis of the Unique Intermediate Dehydro-F 420-0 in Mycobacteria. mSystems 2020; 5:e00389-20. [PMID: 32430409 PMCID: PMC7253369 DOI: 10.1128/msystems.00389-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 05/04/2020] [Indexed: 11/29/2022] Open
Abstract
F420 is a low-potential redox cofactor used by diverse bacteria and archaea. In mycobacteria, this cofactor has multiple roles, including adaptation to redox stress, cell wall biosynthesis, and activation of the clinical antitubercular prodrugs pretomanid and delamanid. A recent biochemical study proposed a revised biosynthesis pathway for F420 in mycobacteria; it was suggested that phosphoenolpyruvate served as a metabolic precursor for this pathway, rather than 2-phospholactate as long proposed, but these findings were subsequently challenged. In this work, we combined metabolomic, genetic, and structural analyses to resolve these discrepancies and determine the basis of F420 biosynthesis in mycobacterial cells. We show that, in whole cells of Mycobacterium smegmatis, phosphoenolpyruvate rather than 2-phospholactate stimulates F420 biosynthesis. Analysis of F420 biosynthesis intermediates present in M. smegmatis cells harboring genetic deletions at each step of the biosynthetic pathway confirmed that phosphoenolpyruvate is then used to produce the novel precursor compound dehydro-F420-0. To determine the structural basis of dehydro-F420-0 production, we solved high-resolution crystal structures of the enzyme responsible (FbiA) in apo-, substrate-, and product-bound forms. These data show the essential role of a single divalent cation in coordinating the catalytic precomplex of this enzyme and demonstrate that dehydro-F420-0 synthesis occurs through a direct substrate transfer mechanism. Together, these findings resolve the biosynthetic pathway of F420 in mycobacteria and have significant implications for understanding the emergence of antitubercular prodrug resistance.IMPORTANCE Mycobacteria are major environmental microorganisms and cause many significant diseases, including tuberculosis. Mycobacteria make an unusual vitamin-like compound, F420, and use it to both persist during stress and resist antibiotic treatment. Understanding how mycobacteria make F420 is important, as this process can be targeted to create new drugs to combat infections like tuberculosis. In this study, we show that mycobacteria make F420 in a way that is different from other bacteria. We studied the molecular machinery that mycobacteria use to make F420, determining the chemical mechanism for this process and identifying a novel chemical intermediate. These findings also have clinical relevance, given that two new prodrugs for tuberculosis treatment are activated by F420.
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Affiliation(s)
- Rhys Grinter
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Blair Ney
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- CSIRO Land & Water, Canberra, ACT, Australia
- Research School of Chemistry, Australian National University, Canberra, ACT, Australia
| | - Rajini Brammananth
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Christopher K Barlow
- Department of Biochemistry, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Monash Proteomics & Metabolomics Facility, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Paul R F Cordero
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - David L Gillett
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Thierry Izoré
- Department of Biochemistry, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Max J Cryle
- Department of Biochemistry, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Liam K Harold
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Gregory M Cook
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - George Taiaroa
- Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Deborah A Williamson
- Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | | | | | | | - Paul K Crellin
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Colin J Jackson
- Research School of Chemistry, Australian National University, Canberra, ACT, Australia
| | - Ralf B Schittenhelm
- Department of Biochemistry, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Monash Proteomics & Metabolomics Facility, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Ross L Coppel
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Chris Greening
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
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11
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Wang Y, Fan L, Tuyishime P, Liu J, Zhang K, Gao N, Zhang Z, Ni X, Feng J, Yuan Q, Ma H, Zheng P, Sun J, Ma Y. Adaptive laboratory evolution enhances methanol tolerance and conversion in engineered Corynebacterium glutamicum. Commun Biol 2020; 3:217. [PMID: 32382107 PMCID: PMC7205612 DOI: 10.1038/s42003-020-0954-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 04/03/2020] [Indexed: 12/26/2022] Open
Abstract
Synthetic methylotrophy has recently been intensively studied to achieve methanol-based biomanufacturing of fuels and chemicals. However, attempts to engineer platform microorganisms to utilize methanol mainly focus on enzyme and pathway engineering. Herein, we enhanced methanol bioconversion of synthetic methylotrophs by improving cellular tolerance to methanol. A previously engineered methanol-dependent Corynebacterium glutamicum is subjected to adaptive laboratory evolution with elevated methanol content. Unexpectedly, the evolved strain not only tolerates higher concentrations of methanol but also shows improved growth and methanol utilization. Transcriptome analysis suggests increased methanol concentrations rebalance methylotrophic metabolism by down-regulating glycolysis and up-regulating amino acid biosynthesis, oxidative phosphorylation, ribosome biosynthesis, and parts of TCA cycle. Mutations in the O-acetyl-l-homoserine sulfhydrylase Cgl0653 catalyzing formation of l-methionine analog from methanol and methanol-induced membrane-bound transporter Cgl0833 are proven crucial for methanol tolerance. This study demonstrates the importance of tolerance engineering in developing superior synthetic methylotrophs. Wang et al. improve the methanol tolerance for the synthetic methylotroph, Corynebacterium glutamicum. They generate 3 new strains by directed evolution and use biochemical, transcriptomic, and genetic approaches to characterize the pathways underlying the enhanced methanol metabolism. Their findings are important for biomanufacturing purposes.
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Affiliation(s)
- Yu Wang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Liwen Fan
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,School of Life Sciences, University of Science and Technology of China, Hefei, 230026, China
| | - Philibert Tuyishime
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Jiao Liu
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Kun Zhang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ning Gao
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhihui Zhang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaomeng Ni
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Jinhui Feng
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Qianqian Yuan
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Hongwu Ma
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Ping Zheng
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China. .,School of Life Sciences, University of Science and Technology of China, Hefei, 230026, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Jibin Sun
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Yanhe Ma
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
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12
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Rainczuk AK, Klatt S, Yamaryo-Botté Y, Brammananth R, McConville MJ, Coppel RL, Crellin PK. MtrP, a putative methyltransferase in Corynebacteria, is required for optimal membrane transport of trehalose mycolates. J Biol Chem 2020; 295:6108-6119. [PMID: 32217691 DOI: 10.1074/jbc.ra119.011688] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 03/22/2020] [Indexed: 12/17/2022] Open
Abstract
Pathogenic bacteria of the genera Mycobacterium and Corynebacterium cause severe human diseases such as tuberculosis (Mycobacterium tuberculosis) and diphtheria (Corynebacterium diphtheriae). The cells of these species are surrounded by protective cell walls rich in long-chain mycolic acids. These fatty acids are conjugated to the disaccharide trehalose on the cytoplasmic side of the bacterial cell membrane. They are then transported across the membrane to the periplasm where they act as donors for other reactions. We have previously shown that transient acetylation of the glycolipid trehalose monohydroxycorynomycolate (hTMCM) enables its efficient transport to the periplasm in Corynebacterium glutamicum and that acetylation is mediated by the membrane protein TmaT. Here, we show that a putative methyltransferase, encoded at the same genetic locus as TmaT, is also required for optimal hTMCM transport. Deletion of the C. glutamicum gene NCgl2764 (Rv0224c in M. tuberculosis) abolished acetyltrehalose monocorynomycolate (AcTMCM) synthesis, leading to accumulation of hTMCM in the inner membrane and delaying its conversion to trehalose dihydroxycorynomycolate (h2TDCM). Complementation with NCgl2764 normalized turnover of hTMCM to h2TDCM. In contrast, complementation with NCgl2764 derivatives mutated at residues essential for methyltransferase activity failed to rectify the defect, suggesting that NCgl2764/Rv0224c encodes a methyltransferase, designated here as MtrP. Comprehensive analyses of the individual mtrP and tmaT mutants and of a double mutant revealed strikingly similar changes across several lipid classes compared with WT bacteria. These findings indicate that both MtrP and TmaT have nonredundant roles in regulating AcTMCM synthesis, revealing additional complexity in the regulation of trehalose mycolate transport in the Corynebacterineae.
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Affiliation(s)
- Arek K Rainczuk
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Stephan Klatt
- Department of Biochemistry and Molecular Biology, Bio21 Institute of Molecular Sciences and Biotechnology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Yoshiki Yamaryo-Botté
- Department of Biochemistry and Molecular Biology, Bio21 Institute of Molecular Sciences and Biotechnology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Rajini Brammananth
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Malcolm J McConville
- Department of Biochemistry and Molecular Biology, Bio21 Institute of Molecular Sciences and Biotechnology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Ross L Coppel
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Paul K Crellin
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Victoria 3800, Australia.
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13
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Sher JW, Lim HC, Bernhardt TG. Global phenotypic profiling identifies a conserved actinobacterial cofactor for a bifunctional PBP-type cell wall synthase. eLife 2020; 9:54761. [PMID: 32167475 PMCID: PMC7205459 DOI: 10.7554/elife.54761] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 03/12/2020] [Indexed: 12/11/2022] Open
Abstract
Members of the Corynebacterineae suborder of Actinobacteria have a unique cell surface architecture and, unlike most well-studied bacteria, grow by tip-extension. To investigate the distinct morphogenic mechanisms shared by these organisms, we performed a genome-wide phenotypic profiling analysis using Corynebacterium glutamicum as a model. A high-density transposon mutagenized library was challenged with a panel of antibiotics and other stresses. The fitness of mutants in each gene under each condition was then assessed by transposon-sequencing. Clustering of the resulting phenotypic fingerprints revealed a role for several genes of previously unknown function in surface biogenesis. Further analysis identified CofA (Cgp_0016) as an interaction partner of the peptidoglycan synthase PBP1a that promotes its stable accumulation at sites of polar growth. The related Mycobacterium tuberculosis proteins were also found to interact, highlighting the utility of our dataset for uncovering conserved principles of morphogenesis for this clinically relevant bacterial suborder.
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Affiliation(s)
- Joel W Sher
- Department of Microbiology, Harvard Medical School, Boston, United States
| | - Hoong Chuin Lim
- Department of Microbiology, Harvard Medical School, Boston, United States
| | - Thomas G Bernhardt
- Department of Microbiology, Harvard Medical School, Boston, United States.,Howard Hughes Medical Institute, Chevy Chase, United States
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14
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Belardinelli JM, Stevens CM, Li W, Tan YZ, Jones V, Mancia F, Zgurskaya HI, Jackson M. The MmpL3 interactome reveals a complex crosstalk between cell envelope biosynthesis and cell elongation and division in mycobacteria. Sci Rep 2019; 9:10728. [PMID: 31341202 PMCID: PMC6656915 DOI: 10.1038/s41598-019-47159-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 07/08/2019] [Indexed: 01/19/2023] Open
Abstract
Integral membrane transporters of the Mycobacterial Membrane Protein Large (MmpL) family and their interactome play important roles in the synthesis and export of mycobacterial outer membrane lipids. Despite the current interest in the mycolic acid transporter, MmpL3, from the perspective of drug discovery, the nature and biological significance of its interactome remain largely unknown. We here report on a genome-wide screening by two-hybrid system for MmpL3 binding partners. While a surprisingly low number of proteins involved in mycolic acid biosynthesis was found to interact with MmpL3, numerous enzymes and transporters participating in the biogenesis of peptidoglycan, arabinogalactan and lipoglycans, and the cell division regulatory protein, CrgA, were identified among the hits. Surface plasmon resonance and co-immunoprecipitation independently confirmed physical interactions for three proteins in vitro and/or in vivo. Results are in line with the focal localization of MmpL3 at the poles and septum of actively-growing bacilli where the synthesis of all major constituents of the cell wall core are known to occur, and are further suggestive of a role for MmpL3 in the coordination of new cell wall deposition during cell septation and elongation. This novel aspect of the physiology of MmpL3 may contribute to the extreme vulnerability and high therapeutic potential of this transporter.
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Affiliation(s)
- Juan Manuel Belardinelli
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, 80523-1682, USA
| | - Casey M Stevens
- University of Oklahoma, Department of Chemistry and Biochemistry, 101 Stephenson Parkway, Norman, OK, 73019, USA
| | - Wei Li
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, 80523-1682, USA
| | - Yong Zi Tan
- Department of Physiology and Cellular Biophysics, Columbia University, 1150 St. Nicholas Avenue, New York, NY, 10032, USA
| | - Victoria Jones
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, 80523-1682, USA
| | - Filippo Mancia
- Department of Physiology and Cellular Biophysics, Columbia University, 1150 St. Nicholas Avenue, New York, NY, 10032, USA
| | - Helen I Zgurskaya
- University of Oklahoma, Department of Chemistry and Biochemistry, 101 Stephenson Parkway, Norman, OK, 73019, USA
| | - Mary Jackson
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, 80523-1682, USA.
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15
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Mycobacterial phosphatase PstP regulates global serine threonine phosphorylation and cell division. Sci Rep 2019; 9:8337. [PMID: 31171861 PMCID: PMC6554272 DOI: 10.1038/s41598-019-44841-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 05/24/2019] [Indexed: 12/28/2022] Open
Abstract
Protein phosphatase PstP is conserved throughout the Actinobacteria in a genetic locus related to cell wall synthesis and cell division. In many Actinobacteria it is the sole annotated serine threonine protein phosphatase to counter the activity of multiple serine threonine protein kinases. We used transcriptional knockdown, electron microscopy and comparative phosphoproteomics to investigate the putative dual functions of PstP as a specific regulator of cell division and as a global regulator of protein phosphorylation. Comparative phosphoproteomics in the early stages of PstP depletion showed hyperphosphorylation of protein kinases and their substrates, confirming PstP as a negative regulator of kinase activity and global serine and threonine phosphorylation. Analysis of the 838 phosphorylation sites that changed significantly, suggested that PstP may regulate diverse phosphoproteins, preferentially at phosphothreonine near acidic residues, near the protein termini, and within membrane associated proteins. Increased phosphorylation of the activation loop of protein kinase B (PknB) and of the essential PknB substrate CwlM offer possible explanations for the requirement for pstP for growth and for cell wall defects when PstP was depleted.
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16
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Abstract
Actinobacteria is a group of diverse bacteria. Most species in this class of bacteria are filamentous aerobes found in soil, including the genus Streptomyces perhaps best known for their fascinating capabilities of producing antibiotics. These bacteria typically have a Gram-positive cell envelope, comprised of a plasma membrane and a thick peptidoglycan layer. However, there is a notable exception of the Corynebacteriales order, which has evolved a unique type of outer membrane likely as a consequence of convergent evolution. In this chapter, we will focus on the unique cell envelope of this order. This cell envelope features the peptidoglycan layer that is covalently modified by an additional layer of arabinogalactan . Furthermore, the arabinogalactan layer provides the platform for the covalent attachment of mycolic acids , some of the longest natural fatty acids that can contain ~100 carbon atoms per molecule. Mycolic acids are thought to be the main component of the outer membrane, which is composed of many additional lipids including trehalose dimycolate, also known as the cord factor. Importantly, a subset of bacteria in the Corynebacteriales order are pathogens of human and domestic animals, including Mycobacterium tuberculosis. The surface coat of these pathogens are the first point of contact with the host immune system, and we now know a number of host receptors specific to molecular patterns exposed on the pathogen's surface, highlighting the importance of understanding how the cell envelope of Actinobacteria is structured and constructed. This chapter describes the main structural and biosynthetic features of major components found in the actinobacterial cell envelopes and highlights the key differences between them.
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Affiliation(s)
- Kathryn C Rahlwes
- Department of Microbiology, University of Massachusetts, 639 North Pleasant Street, Amherst, MA, 01003, USA
| | - Ian L Sparks
- Department of Microbiology, University of Massachusetts, 639 North Pleasant Street, Amherst, MA, 01003, USA
| | - Yasu S Morita
- Department of Microbiology, University of Massachusetts, 639 North Pleasant Street, Amherst, MA, 01003, USA.
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17
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Rahlwes KC, Ha SA, Motooka D, Mayfield JA, Baumoel LR, Strickland JN, Torres-Ocampo AP, Nakamura S, Morita YS. The cell envelope-associated phospholipid-binding protein LmeA is required for mannan polymerization in mycobacteria. J Biol Chem 2017; 292:17407-17417. [PMID: 28855252 DOI: 10.1074/jbc.m117.804377] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 08/28/2017] [Indexed: 11/06/2022] Open
Abstract
The integrity of the distinguishing, multilaminate cell envelope surrounding mycobacteria is critical to their survival and pathogenesis. The prevalence of phosphatidylinositol mannosides in the cell envelope suggests an important role in the mycobacterial life cycle. Indeed, deletion of the pimE gene (ΔpimE) encoding the first committed step in phosphatidylinositol hexamannoside biosynthesis in Mycobacterium smegmatis results in the formation of smaller colonies than wild-type colonies on Middlebrook 7H10 agar. To further investigate potential contributors to cell-envelope mannan biosynthesis while taking advantage of this colony morphology defect, we isolated spontaneous suppressor mutants of ΔpimE that reverted to wild-type colony size. Of 22 suppressor mutants, 6 accumulated significantly shorter lipomannan or lipoarabinomannan. Genome sequencing of these mutants revealed mutations in genes involved in the lipomannan/lipoarabinomannan biosynthesis, such as those encoding the arabinosyltransferase EmbC and the mannosyltransferase MptA. Furthermore, we identified three mutants carrying a mutation in a previously uncharacterized gene, MSMEG_5785, that we designated lmeA Complementation of these suppressor mutants with lmeA restored the original ΔpimE phenotypes and deletion of lmeA in wild-type M. smegmatis resulted in smaller lipomannan, as observed in the suppressor mutants. LmeA carries a predicted N-terminal signal peptide, and density gradient fractionation and detergent extractability experiments indicated that LmeA localizes to the cell envelope. Using a lipid ELISA, we found that LmeA binds to plasma membrane phospholipids, such as phosphatidylethanolamine and phosphatidylinositol. LmeA is widespread throughout the Corynebacteriales; therefore, we concluded that LmeA is an evolutionarily conserved cell-envelope protein critical for controlling the mannan chain length of lipomannan/lipoarabinomannan.
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Affiliation(s)
- Kathryn C Rahlwes
- From the Department of Microbiology, University of Massachusetts, Amherst, MA 01003
| | - Stephanie A Ha
- From the Department of Microbiology, University of Massachusetts, Amherst, MA 01003
| | - Daisuke Motooka
- the Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan
| | - Jacob A Mayfield
- the Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02445
| | - Lisa R Baumoel
- From the Department of Microbiology, University of Massachusetts, Amherst, MA 01003
| | - Justin N Strickland
- From the Department of Microbiology, University of Massachusetts, Amherst, MA 01003
| | - Ana P Torres-Ocampo
- From the Department of Microbiology, University of Massachusetts, Amherst, MA 01003
| | - Shota Nakamura
- the Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan
| | - Yasu S Morita
- From the Department of Microbiology, University of Massachusetts, Amherst, MA 01003,
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