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Arejan NH, Czapski DR, Buonomo JA, Boutte CC. MmpL3, Wag31 and PlrA are involved in coordinating polar growth with peptidoglycan metabolism and nutrient availability. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.29.591792. [PMID: 38746181 PMCID: PMC11092516 DOI: 10.1101/2024.04.29.591792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Cell growth in mycobacteria involves cell wall expansion that is restricted to the cell poles. The DivIVA homolog Wag31 is required for this process, but the molecular mechanism and protein partners of Wag31 have not been described. In this study of Mycobacterium smegmatis, we identify a connection between wag31 and trehalose monomycolate (TMM) transporter mmpl3 in a suppressor screen, and show that Wag31 and polar regulator PlrA are required for MmpL3's polar localization. In addition, the localization of PlrA and MmpL3 are responsive to nutrient and energy deprivation and inhibition of peptidoglycan metabolism. We show that inhibition of MmpL3 causes delocalized cell wall metabolism, but does not delocalize MmpL3 itself. We found that cells with an MmpL3 C-terminal truncation, which is defective for localization, have only minor defects in polar growth, but are impaired in their ability to downregulate cell wall metabolism under stress. Our work suggests that, in addition to its established function in TMM transport, MmpL3 has a second function in regulating global cell wall metabolism in response to stress. Our data are consistent with a model in which the presence of TMMs in the periplasm stimulates polar elongation, and in which the connection between Wag31, PlrA and the C-terminus of MmpL3 is involved in detecting and responding to stress in order to coordinate synthesis of the different layers of the mycobacterial cell wall in changing conditions.
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Affiliation(s)
| | - Desiree R Czapski
- Department of Chemistry and Biochemistry, University of Texas, Arlington
| | - Joseph A Buonomo
- Department of Chemistry and Biochemistry, University of Texas, Arlington
| | - Cara C Boutte
- Department of Biology, University of Texas, Arlington
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2
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Sparks IL, Kado T, Prithviraj M, Nijjer J, Yan J, Morita YS. Lipoarabinomannan mediates localized cell wall integrity during division in mycobacteria. Nat Commun 2024; 15:2191. [PMID: 38467648 PMCID: PMC10928101 DOI: 10.1038/s41467-024-46565-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 02/29/2024] [Indexed: 03/13/2024] Open
Abstract
The growth and division of mycobacteria, which include clinically relevant pathogens, deviate from that of canonical bacterial models. Despite their Gram-positive ancestry, mycobacteria synthesize and elongate a diderm envelope asymmetrically from the poles, with the old pole elongating more robustly than the new pole. The phosphatidylinositol-anchored lipoglycans lipomannan (LM) and lipoarabinomannan (LAM) are cell envelope components critical for host-pathogen interactions, but their physiological functions in mycobacteria remained elusive. In this work, using biosynthetic mutants of these lipoglycans, we examine their roles in maintaining cell envelope integrity in Mycobacterium smegmatis and Mycobacterium tuberculosis. We find that mutants defective in producing mature LAM fail to maintain rod cell shape specifically at the new pole and para-septal regions whereas a mutant that produces a larger LAM becomes multi-septated. Therefore, LAM plays critical and distinct roles at subcellular locations associated with division in mycobacteria, including maintenance of local cell wall integrity and septal placement.
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Affiliation(s)
- Ian L Sparks
- Department of Microbiology, University of Massachusetts, Amherst, MA, USA
| | - Takehiro Kado
- Department of Microbiology, University of Massachusetts, Amherst, MA, USA
| | | | - Japinder Nijjer
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
- Quantitative Biology Institute, Yale University, New Haven, CT, USA
| | - Jing Yan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
- Quantitative Biology Institute, Yale University, New Haven, CT, USA
| | - Yasu S Morita
- Department of Microbiology, University of Massachusetts, Amherst, MA, USA.
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3
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Matusiak I, Strzałka A, Wadach P, Gongerowska-Jac M, Szwajczak E, Szydłowska-Helbrych A, Kepplinger B, Pióro M, Jakimowicz D. The interplay between the polar growth determinant DivIVA, the segregation protein ParA, and their novel interaction partner PapM controls the Mycobacterium smegmatis cell cycle by modulation of DivIVA subcellular distribution. Microbiol Spectr 2023; 11:e0175223. [PMID: 37966202 PMCID: PMC10714820 DOI: 10.1128/spectrum.01752-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 10/06/2023] [Indexed: 11/16/2023] Open
Abstract
IMPORTANCE The genus of Mycobacterium includes important clinical pathogens (M. tuberculosis). Bacteria of this genus share the unusual features of their cell cycle such as asymmetric polar cell elongation and long generation time. Markedly, control of the mycobacterial cell cycle still remains not fully understood. The main cell growth determinant in mycobacteria is the essential protein DivIVA, which is also involved in cell division. DivIVA activity is controlled by phosphorylation, but the mechanism and significance of this process are unknown. Here, we show how the previously established protein interaction partner of DivIVA in mycobacteria, the segregation protein ParA, affects the DivIVA subcellular distribution. We also demonstrate the role of a newly identified M. smegmatis DivIVA and ParA interaction partner, a protein named PapM, and we establish how their interactions are modulated by phosphorylation. Demonstrating that the tripartite interplay affects the mycobacterial cell cycle contributes to the general understanding of mycobacterial growth regulation.
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Affiliation(s)
- Izabela Matusiak
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Agnieszka Strzałka
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Patrycja Wadach
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Martyna Gongerowska-Jac
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | | | | | - Bernhard Kepplinger
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Monika Pióro
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Dagmara Jakimowicz
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
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4
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Martinez M, Petit J, Leyva A, Sogues A, Megrian D, Rodriguez A, Gaday Q, Ben Assaya M, Portela MM, Haouz A, Ducret A, Grangeasse C, Alzari PM, Durán R, Wehenkel AM. Eukaryotic-like gephyrin and cognate membrane receptor coordinate corynebacterial cell division and polar elongation. Nat Microbiol 2023; 8:1896-1910. [PMID: 37679597 PMCID: PMC10522489 DOI: 10.1038/s41564-023-01473-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 08/11/2023] [Indexed: 09/09/2023]
Abstract
The order Corynebacteriales includes major industrial and pathogenic Actinobacteria such as Corynebacterium glutamicum or Mycobacterium tuberculosis. These bacteria have multi-layered cell walls composed of the mycolyl-arabinogalactan-peptidoglycan complex and a polar growth mode, thus requiring tight coordination between the septal divisome, organized around the tubulin-like protein FtsZ, and the polar elongasome, assembled around the coiled-coil protein Wag31. Here, using C. glutamicum, we report the discovery of two divisome members: a gephyrin-like repurposed molybdotransferase (Glp) and its membrane receptor (GlpR). Our results show how cell cycle progression requires interplay between Glp/GlpR, FtsZ and Wag31, showcasing a crucial crosstalk between the divisome and elongasome machineries that might be targeted for anti-mycobacterial drug discovery. Further, our work reveals that Corynebacteriales have evolved a protein scaffold to control cell division and morphogenesis, similar to the gephyrin/GlyR system that mediates synaptic signalling in higher eukaryotes through network organization of membrane receptors and the microtubule cytoskeleton.
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Affiliation(s)
- Mariano Martinez
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Julienne Petit
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Alejandro Leyva
- Analytical Biochemistry and Proteomics Unit, Institut Pasteur de Montevideo, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Adrià Sogues
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
- Structural and Molecular Microbiology, VIB-VUB Center for Structural Biology, VIB, Vrije Universiteit Brussel, Brussels, Belgium
| | - Daniela Megrian
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Azalia Rodriguez
- Analytical Biochemistry and Proteomics Unit, Institut Pasteur de Montevideo, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Quentin Gaday
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Mathildeb Ben Assaya
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Maria Magdalena Portela
- Analytical Biochemistry and Proteomics Unit, Institut Pasteur de Montevideo, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Ahmed Haouz
- Plate-forme de cristallographie, C2RT-Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Adrien Ducret
- Molecular Microbiology and Structural Biochemistry, CNRS UMR 5086, Université de Lyon, Lyon, France
| | - Christophe Grangeasse
- Molecular Microbiology and Structural Biochemistry, CNRS UMR 5086, Université de Lyon, Lyon, France
| | - Pedro M Alzari
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France
| | - Rosario Durán
- Analytical Biochemistry and Proteomics Unit, Institut Pasteur de Montevideo, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay.
| | - Anne Marie Wehenkel
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, Paris, France.
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5
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Kado T, Akbary Z, Motooka D, Sparks IL, Melzer ES, Nakamura S, Rojas ER, Morita YS, Siegrist MS. A cell wall synthase accelerates plasma membrane partitioning in mycobacteria. eLife 2023; 12:e81924. [PMID: 37665120 PMCID: PMC10547480 DOI: 10.7554/elife.81924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 09/02/2023] [Indexed: 09/05/2023] Open
Abstract
Lateral partitioning of proteins and lipids shapes membrane function. In model membranes, partitioning can be influenced both by bilayer-intrinsic factors like molecular composition and by bilayer-extrinsic factors such as interactions with other membranes and solid supports. While cellular membranes can departition in response to bilayer-intrinsic or -extrinsic disruptions, the mechanisms by which they partition de novo are largely unknown. The plasma membrane of Mycobacterium smegmatis spatially and biochemically departitions in response to the fluidizing agent benzyl alcohol, then repartitions upon fluidizer washout. By screening for mutants that are sensitive to benzyl alcohol, we show that the bifunctional cell wall synthase PonA2 promotes membrane partitioning and cell growth during recovery from benzyl alcohol exposure. PonA2's role in membrane repartitioning and regrowth depends solely on its conserved transglycosylase domain. Active cell wall polymerization promotes de novo membrane partitioning and the completed cell wall polymer helps to maintain membrane partitioning. Our work highlights the complexity of membrane-cell wall interactions and establishes a facile model system for departitioning and repartitioning cellular membranes.
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Affiliation(s)
- Takehiro Kado
- Department of Microbiology, University of Massachusetts AmherstAmherstUnited States
| | - Zarina Akbary
- Department of Biology, New York UniversityNew YorkUnited States
| | - Daisuke Motooka
- Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka UniversityOsakaJapan
| | - Ian L Sparks
- Department of Microbiology, University of Massachusetts AmherstAmherstUnited States
| | - Emily S Melzer
- Department of Microbiology, University of Massachusetts AmherstAmherstUnited States
| | - Shota Nakamura
- Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka UniversityOsakaJapan
| | - Enrique R Rojas
- Department of Biology, New York UniversityNew YorkUnited States
| | - Yasu S Morita
- Department of Microbiology, University of Massachusetts AmherstAmherstUnited States
- Molecular and Cellular Graduate Program, University of Massachusetts AmherstAmherstUnited States
| | - M Sloan Siegrist
- Department of Microbiology, University of Massachusetts AmherstAmherstUnited States
- Molecular and Cellular Graduate Program, University of Massachusetts AmherstAmherstUnited States
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6
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Gessner S, Martin ZAM, Reiche MA, Santos JA, Dinkele R, Ramudzuli A, Dhar N, de Wet TJ, Anoosheh S, Lang DM, Aaron J, Chew TL, Herrmann J, Müller R, McKinney JD, Woodgate R, Mizrahi V, Venclovas Č, Lamers MH, Warner DF. Investigating the composition and recruitment of the mycobacterial ImuA'-ImuB-DnaE2 mutasome. eLife 2023; 12:e75628. [PMID: 37530405 PMCID: PMC10421592 DOI: 10.7554/elife.75628] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 08/01/2023] [Indexed: 08/03/2023] Open
Abstract
A DNA damage-inducible mutagenic gene cassette has been implicated in the emergence of drug resistance in Mycobacterium tuberculosis during anti-tuberculosis (TB) chemotherapy. However, the molecular composition and operation of the encoded 'mycobacterial mutasome' - minimally comprising DnaE2 polymerase and ImuA' and ImuB accessory proteins - remain elusive. Following exposure of mycobacteria to DNA damaging agents, we observe that DnaE2 and ImuB co-localize with the DNA polymerase III β subunit (β clamp) in distinct intracellular foci. Notably, genetic inactivation of the mutasome in an imuBAAAAGG mutant containing a disrupted β clamp-binding motif abolishes ImuB-β clamp focus formation, a phenotype recapitulated pharmacologically by treating bacilli with griselimycin and in biochemical assays in which this β clamp-binding antibiotic collapses pre-formed ImuB-β clamp complexes. These observations establish the essentiality of the ImuB-β clamp interaction for mutagenic DNA repair in mycobacteria, identifying the mutasome as target for adjunctive therapeutics designed to protect anti-TB drugs against emerging resistance.
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Affiliation(s)
- Sophia Gessner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Zela Alexandria-Mae Martin
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Laboratory of Microbiology and Microsystems, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
| | - Michael A Reiche
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Advanced Imaging Center, Howard Hughes Medical InstituteAshburnUnited States
| | - Joana A Santos
- Department of Cell and Chemical Biology, Leiden University Medical CenterLeidenNetherlands
| | - Ryan Dinkele
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Atondaho Ramudzuli
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Neeraj Dhar
- Laboratory of Microbiology and Microsystems, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
| | - Timothy J de Wet
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Department of Integrative Biomedical Sciences, University of Cape TownCape TownSouth Africa
| | - Saber Anoosheh
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Dirk M Lang
- Confocal and Light Microscope Imaging Facility, Department of Human Biology, University of Cape TownCape TownSouth Africa
| | - Jesse Aaron
- Advanced Imaging Center, Howard Hughes Medical InstituteAshburnUnited States
| | - Teng-Leong Chew
- Advanced Imaging Center, Howard Hughes Medical InstituteAshburnUnited States
| | - Jennifer Herrmann
- Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrückenGermany
- German Centre for Infection Research (DZIF), Partner Site Hannover-BraunschweigBraunschweigGermany
| | - Rolf Müller
- Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrückenGermany
- German Centre for Infection Research (DZIF), Partner Site Hannover-BraunschweigBraunschweigGermany
| | - John D McKinney
- Laboratory of Microbiology and Microsystems, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
| | - Roger Woodgate
- Laboratory of Genomic Integrity, Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentBethesdaUnited States
| | - Valerie Mizrahi
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, 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
| | | | - Meindert H Lamers
- Department of Cell and Chemical Biology, Leiden University Medical CenterLeidenNetherlands
| | - Digby F Warner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, 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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7
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Kishore V, Gaiwala Sharma SS, Raghunand TR. Septum site placement in Mycobacteria - identification and characterisation of mycobacterial homologues of Escherichia coli MinD. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001359. [PMID: 37526955 PMCID: PMC10482377 DOI: 10.1099/mic.0.001359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 06/22/2023] [Indexed: 08/02/2023]
Abstract
A major virulence trait of Mycobacterium tuberculosis (M. tb) is its ability to enter a dormant state within its human host. Since cell division is intimately linked to metabolic shut down, understanding the mechanism of septum formation and its integration with other events in the division pathway is likely to offer clues to the molecular basis of dormancy. The M. tb genome lacks obvious homologues of several conserved cell division proteins, and this study was aimed at identifying and functionally characterising mycobacterial homologues of the E. coli septum site specification protein MinD (Ec MinD). Sequence homology based analyses suggested that the genomes of both M. tb and the saprophyte Mycobacterium smegmatis (M. smegmatis) encode two putative Ec MinD homologues - Rv1708/MSMEG_3743 and Rv3660c/ MSMEG_6171. Of these, Rv1708/MSMEG_3743 were found to be the true homologues, through complementation of the E. coli ∆minDE mutant HL1, overexpression studies, and structural comparisons. Rv1708 and MSMEG_3743 fully complemented the mini-cell phenotype of HL1, and over-expression of MSMEG_3743 in M. smegmatis led to cell elongation and a drastic decrease in c.f.u. counts, indicating its essentiality in cell-division. MSMEG_3743 displayed ATPase activity, consistent with its containing a conserved Walker A motif. Interaction of Rv1708 with the chromosome associated proteins ScpA and ParB, implied a link between its septum formation role, and chromosome segregation. Comparative structural analyses showed Rv1708 to be closer in similarity to Ec MinD than Rv3660c. In summary we identify Rv1708 and MSMEG_3743 to be homologues of Ec MinD, adding a critical missing piece to the mycobacterial cell division puzzle.
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Affiliation(s)
- Vimal Kishore
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road Hyderabad - 500007, India
- Present address: National Centre for Cell Science (NCCS), NCCS Complex, University of Pune Campus, Pune University Rd, Ganeshkhind, Pune, 411007, India
| | - Sujata S. Gaiwala Sharma
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road Hyderabad - 500007, India
- Present address: Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune 411008, India
| | - Tirumalai R. Raghunand
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road Hyderabad - 500007, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
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8
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Sparks IL, Nijjer J, Yan J, Morita YS. Lipoarabinomannan regulates septation in Mycobacterium smegmatis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.26.534150. [PMID: 36993273 PMCID: PMC10055410 DOI: 10.1101/2023.03.26.534150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The growth and division of mycobacteria, which include several clinically relevant pathogens, deviate significantly from that of canonical bacterial models. Despite their Gram-positive ancestry, mycobacteria synthesize and elongate a diderm envelope asymmetrically from the poles, with the old pole elongating more robustly than the new pole. In addition to being structurally distinct, the molecular components of the mycobacterial envelope are also evolutionarily unique, including the phosphatidylinositol-anchored lipoglycans lipomannan (LM) and lipoarabinomannan (LAM). LM and LAM modulate host immunity during infection, but their role outside of intracellular survival remains poorly understood, despite their widespread conservation among non-pathogenic and opportunistically pathogenic mycobacteria. Previously, Mycobacterium smegmatis and Mycobacterium tuberculosis mutants producing structurally altered LM and LAM were shown to grow slowly under certain conditions and to be more sensitive to antibiotics, suggesting that mycobacterial lipoglycans may support cellular integrity or growth. To test this, we constructed multiple biosynthetic lipoglycan mutants of M. smegmatis and determined the effect of each mutation on cell wall biosynthesis, envelope integrity, and division. We found that mutants deficient in LAM, but not LM, fail to maintain cell wall integrity in a medium-dependent manner, with envelope deformations specifically associated with septa and new poles. Conversely, a mutant producing abnormally large LAM formed multiseptated cells in way distinct from that observed in a septal hydrolase mutant. These results show that LAM plays critical and distinct roles at subcellular locations associated with division in mycobacteria, including maintenance of local cell envelope integrity and septal placement.
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Affiliation(s)
- Ian L. Sparks
- Department of Microbiology, University of Massachusetts, Amherst, MA, USA
| | - Japinder Nijjer
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven CT, USA
- Quantitative Biology Institute, Yale University, New Haven, CT, USA
| | - Jing Yan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven CT, USA
- Quantitative Biology Institute, Yale University, New Haven, CT, USA
| | - Yasu S. Morita
- Department of Microbiology, University of Massachusetts, Amherst, MA, USA
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9
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Martinez M, Petit J, Leyva A, Sogues A, Megrian D, Rodriguez A, Gaday Q, Ben Assaya M, Portela M, Haouz A, Ducret A, Grangeasse C, Alzari PM, Durán R, Wehenkel A. Eukaryotic-like gephyrin and cognate membrane receptor coordinate corynebacterial cell division and polar elongation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.01.526586. [PMID: 36778425 PMCID: PMC9915583 DOI: 10.1101/2023.02.01.526586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The order Corynebacteriales includes major industrial and pathogenic actinobacteria such as Corynebacterium glutamicum or Mycobacterium tuberculosis . Their elaborate multi-layered cell wall, composed primarily of the mycolyl-arabinogalactan-peptidoglycan complex, and their polar growth mode impose a stringent coordination between the septal divisome, organized around the tubulin-like protein FtsZ, and the polar elongasome, assembled around the tropomyosin-like protein Wag31. Here, we report the identification of two new divisome members, a gephyrin-like repurposed molybdotransferase (GLP) and its membrane receptor (GLPR). We show that the interplay between the GLPR/GLP module, FtsZ and Wag31 is crucial for orchestrating cell cycle progression. Our results provide a detailed molecular understanding of the crosstalk between two essential machineries, the divisome and elongasome, and reveal that Corynebacteriales have evolved a protein scaffold to control cell division and morphogenesis similar to the gephyrin/GlyR system that in higher eukaryotes mediates synaptic signaling through network organization of membrane receptors and the microtubule cytoskeleton.
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Affiliation(s)
- M. Martinez
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, F-75015 Paris, France
| | - J. Petit
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, F-75015 Paris, France
| | - A. Leyva
- Analytical Biochemistry and Proteomics Unit, Institut Pasteur de Montevideo, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - A. Sogues
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, F-75015 Paris, France
| | - D. Megrian
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, F-75015 Paris, France
| | - A. Rodriguez
- Analytical Biochemistry and Proteomics Unit, Institut Pasteur de Montevideo, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Q. Gaday
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, F-75015 Paris, France
| | - M. Ben Assaya
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, F-75015 Paris, France
| | - M. Portela
- Analytical Biochemistry and Proteomics Unit, Institut Pasteur de Montevideo, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - A. Haouz
- Plate-forme de cristallographie, C2RT-Institut Pasteur, CNRS, UMR 3528, Université Paris Cité, F-75015 Paris, France
| | - A. Ducret
- Molecular Microbiology and Structural Biochemistry, CNRS UMR 5086, Université de Lyon, 7 passage du Vercors, 69367 Lyon, France
| | - C. Grangeasse
- Molecular Microbiology and Structural Biochemistry, CNRS UMR 5086, Université de Lyon, 7 passage du Vercors, 69367 Lyon, France
| | - P. M. Alzari
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, F-75015 Paris, France
| | - R. Durán
- Analytical Biochemistry and Proteomics Unit, Institut Pasteur de Montevideo, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - A. Wehenkel
- Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, Université Paris Cité, F-75015 Paris, France
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10
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Abstract
The genus Mycobacterium contains several slow-growing human pathogens, including Mycobacterium tuberculosis, Mycobacterium leprae, and Mycobacterium avium. Mycobacterium smegmatis is a nonpathogenic and fast growing species within this genus. In 1990, a mutant of M. smegmatis, designated mc2155, that could be transformed with episomal plasmids was isolated, elevating M. smegmatis to model status as the ideal surrogate for mycobacterial research. Classical bacterial models, such as Escherichia coli, were inadequate for mycobacteria research because they have low genetic conservation, different physiology, and lack the novel envelope structure that distinguishes the Mycobacterium genus. By contrast, M. smegmatis encodes thousands of conserved mycobacterial gene orthologs and has the same cell architecture and physiology. Dissection and characterization of conserved genes, structures, and processes in genetically tractable M. smegmatis mc2155 have since provided previously unattainable insights on these same features in its slow-growing relatives. Notably, tuberculosis (TB) drugs, including the first-line drugs isoniazid and ethambutol, are active against M. smegmatis, but not against E. coli, allowing the identification of their physiological targets. Furthermore, Bedaquiline, the first new TB drug in 40 years, was discovered through an M. smegmatis screen. M. smegmatis has become a model bacterium, not only for M. tuberculosis, but for all other Mycobacterium species and related genera. With a repertoire of bioinformatic and physical resources, including the recently established Mycobacterial Systems Resource, M. smegmatis will continue to accelerate mycobacterial research and advance the field of microbiology.
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11
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Habibi Arejan N, Ensinck D, Diacovich L, Patel PB, Quintanilla SY, Emami Saleh A, Gramajo H, Boutte CC. Polar protein Wag31 both activates and inhibits cell wall metabolism at the poles and septum. Front Microbiol 2023; 13:1085918. [PMID: 36713172 PMCID: PMC9878328 DOI: 10.3389/fmicb.2022.1085918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 12/20/2022] [Indexed: 01/15/2023] Open
Abstract
Mycobacterial cell elongation occurs at the cell poles; however, it is not clear how cell wall insertion is restricted to the pole or how it is organized. Wag31 is a pole-localized cytoplasmic protein that is essential for polar growth, but its molecular function has not been described. In this study we used alanine scanning mutagenesis to identify Wag31 residues involved in cell morphogenesis. Our data show that Wag31 helps to control proper septation as well as new and old pole elongation. We have identified key amino acid residues involved in these essential functions. Enzyme assays revealed that Wag31 interacts with lipid metabolism by modulating acyl-CoA carboxylase (ACCase) activity. We show that Wag31 does not control polar growth by regulating the localization of cell wall precursor enzymes to the Intracellular Membrane Domain, and we also demonstrate that phosphorylation of Wag31 does not substantively regulate peptidoglycan metabolism. This work establishes new regulatory functions of Wag31 in the mycobacterial cell cycle and clarifies the need for new molecular models of Wag31 function.
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Affiliation(s)
- Neda Habibi Arejan
- Department of Biology, University of Texas at Arlington, Arlington, TX, United States
| | - Delfina Ensinck
- Laboratory of Physiology and Genetics of Actinomycetes, Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Lautaro Diacovich
- Laboratory of Physiology and Genetics of Actinomycetes, Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | | | | | - Arash Emami Saleh
- Department of Civil Engineering, University of Texas at Arlington, Arlington, TX, United States
| | - Hugo Gramajo
- Laboratory of Physiology and Genetics of Actinomycetes, Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Cara C. Boutte
- Department of Biology, University of Texas at Arlington, Arlington, TX, United States,*Correspondence: Cara C. Boutte,
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12
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Quintanilla SY, Arejan NH, Patel PB, Boutte CC. PlrA (MSMEG_5223) is an essential polar growth regulator in Mycobacterium smegmatis. PLoS One 2023; 18:e0280336. [PMID: 36634117 PMCID: PMC9836265 DOI: 10.1371/journal.pone.0280336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 12/27/2022] [Indexed: 01/13/2023] Open
Abstract
Mycobacteria expand their cell walls at the cell poles in a manner that is not well described at the molecular level. In this study, we identify a new polar factor, PlrA, that is involved in restricting peptidoglycan metabolism to the cell poles in Mycobacterium smegmatis. We establish that only the N-terminal membrane domain of PlrA is essential. We show that depletion of plrA pheno-copies depletion of polar growth factor Wag31, and that PlrA is involved in regulating the Wag31 polar foci.
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Affiliation(s)
- Samantha Y. Quintanilla
- Department of Biology, University of Texas Arlington, Arlington, TX, United States of America
| | - Neda Habibi Arejan
- Department of Biology, University of Texas Arlington, Arlington, TX, United States of America
| | - Parthvi B. Patel
- Department of Biology, University of Texas Arlington, Arlington, TX, United States of America
| | - Cara C. Boutte
- Department of Biology, University of Texas Arlington, Arlington, TX, United States of America
- * E-mail:
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13
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Evolutionary scaling of maximum growth rate with organism size. Sci Rep 2022; 12:22586. [PMID: 36585440 PMCID: PMC9803686 DOI: 10.1038/s41598-022-23626-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 11/02/2022] [Indexed: 12/31/2022] Open
Abstract
Data from nearly 1000 species reveal the upper bound to rates of biomass production achievable by natural selection across the Tree of Life. For heterotrophs, maximum growth rates scale positively with organism size in bacteria but negatively in eukaryotes, whereas for phototrophs, the scaling is negligible for cyanobacteria and weakly negative for eukaryotes. These results have significant implications for understanding the bioenergetic consequences of the transition from prokaryotes to eukaryotes, and of the expansion of some groups of the latter into multicellularity. The magnitudes of the scaling coefficients for eukaryotes are significantly lower than expected under any proposed physical-constraint model. Supported by genomic, bioenergetic, and population-genetic data and theory, an alternative hypothesis for the observed negative scaling in eukaryotes postulates that growth-diminishing mutations with small effects passively accumulate with increasing organism size as a consequence of associated increases in the power of random genetic drift. In contrast, conditional on the structural and functional features of ribosomes, natural selection has been able to promote bacteria with the fastest possible growth rates, implying minimal conflicts with both bioenergetic constraints and random genetic drift. If this extension of the drift-barrier hypothesis is correct, the interpretations of comparative studies of biological traits that have traditionally ignored differences in population-genetic environments will require revisiting.
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14
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Mishra S, Saito K. Clinically encountered growth phenotypes of tuberculosis-causing bacilli and their in vitro study: A review. Front Cell Infect Microbiol 2022; 12:1029111. [PMID: 36439231 PMCID: PMC9684195 DOI: 10.3389/fcimb.2022.1029111] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 10/20/2022] [Indexed: 07/11/2024] Open
Abstract
The clinical manifestations of tuberculosis (TB) vary widely in severity, site of infection, and outcomes of treatment-leading to simultaneous efforts to individualize therapy safely and to search for shorter regimens that can be successfully used across the clinical spectrum. In these endeavors, clinicians and researchers alike employ mycobacterial culture in rich media. However, even within the same patient, individual bacilli among the population can exhibit substantial variability in their culturability. Bacilli in vitro also demonstrate substantial heterogeneity in replication rate and cultivation requirements, as well as susceptibility to killing by antimicrobials. Understanding parallels in clinical, ex vivo and in vitro growth phenotype diversity may be key to identifying those phenotypes responsible for treatment failure, relapse, and the reactivation of bacilli that progresses TB infection to disease. This review briefly summarizes the current role of mycobacterial culture in the care of patients with TB and the ex vivo evidence of variability in TB culturability. We then discuss current advances in in vitro models that study heterogenous subpopulations within a genetically identical bulk culture, with an emphasis on the effect of oxidative stress on bacillary cultivation requirements. The review highlights the complexity that heterogeneity in mycobacterial growth brings to the interpretation of culture in clinical settings and research. It also underscores the intricacies present in the interplay between growth phenotypes and antimicrobial susceptibility. Better understanding of population dynamics and growth requirements over time and space promises to aid both the attempts to individualize TB treatment and to find uniformly effective therapies.
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Affiliation(s)
- Saurabh Mishra
- Department of Microbiology and Immunology, Weill Cornell Medicine, New York, NY, United States
| | - Kohta Saito
- Department of Medicine, Weill Cornell Medicine, New York, NY, United States
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15
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Jones RM, Adams KN, Eldesouky HE, Sherman DR. The evolving biology of Mycobacterium tuberculosis drug resistance. Front Cell Infect Microbiol 2022; 12:1027394. [PMID: 36275024 PMCID: PMC9579286 DOI: 10.3389/fcimb.2022.1027394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 09/20/2022] [Indexed: 01/13/2023] Open
Abstract
Tuberculosis, caused by Mycobacterium tuberculosis (Mtb) is an ancient disease that has remained a leading cause of infectious death. Mtb has evolved drug resistance to every antibiotic regimen ever introduced, greatly complicating treatment, lowering rates of cure and menacing TB control in parts of the world. As technology has advanced, our understanding of antimicrobial resistance has improved, and our models of the phenomenon have evolved. In this review, we focus on recent research progress that supports an updated model for the evolution of drug resistance in Mtb. We highlight the contribution of drug tolerance on the path to resistance, and the influence of heterogeneity on tolerance. Resistance is likely to remain an issue for as long as drugs are needed to treat TB. However, with technology driving new insights and careful management of newly developed resources, antimicrobial resistance need not continue to threaten global progress against TB, as it has done for decades.
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Affiliation(s)
| | | | | | - David R. Sherman
- Department of Microbiology, University of Washington, Seattle, WA, United States
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16
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Liebenberg D, Gordhan BG, Kana BD. Drug resistant tuberculosis: Implications for transmission, diagnosis, and disease management. Front Cell Infect Microbiol 2022; 12:943545. [PMID: 36211964 PMCID: PMC9538507 DOI: 10.3389/fcimb.2022.943545] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 09/06/2022] [Indexed: 01/17/2023] Open
Abstract
Drug resistant tuberculosis contributes significantly to the global burden of antimicrobial resistance, often consuming a large proportion of the healthcare budget and associated resources in many endemic countries. The rapid emergence of resistance to newer tuberculosis therapies signals the need to ensure appropriate antibiotic stewardship, together with a concerted drive to develop new regimens that are active against currently circulating drug resistant strains. Herein, we highlight that the current burden of drug resistant tuberculosis is driven by a combination of ongoing transmission and the intra-patient evolution of resistance through several mechanisms. Global control of tuberculosis will require interventions that effectively address these and related aspects. Interrupting tuberculosis transmission is dependent on the availability of novel rapid diagnostics which provide accurate results, as near-patient as is possible, together with appropriate linkage to care. Contact tracing, longitudinal follow-up for symptoms and active mapping of social contacts are essential elements to curb further community-wide spread of drug resistant strains. Appropriate prophylaxis for contacts of drug resistant index cases is imperative to limit disease progression and subsequent transmission. Preventing the evolution of drug resistant strains will require the development of shorter regimens that rapidly eliminate all populations of mycobacteria, whilst concurrently limiting bacterial metabolic processes that drive drug tolerance, mutagenesis and the ultimate emergence of resistance. Drug discovery programs that specifically target bacterial genetic determinants associated with these processes will be paramount to tuberculosis eradication. In addition, the development of appropriate clinical endpoints that quantify drug tolerant organisms in sputum, such as differentially culturable/detectable tubercle bacteria is necessary to accurately assess the potential of new therapies to effectively shorten treatment duration. When combined, this holistic approach to addressing the critical problems associated with drug resistance will support delivery of quality care to patients suffering from tuberculosis and bolster efforts to eradicate this disease.
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17
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Marro FC, Laurent F, Josse J, Blocker AJ. Methods to monitor bacterial growth and replicative rates at the single-cell level. FEMS Microbiol Rev 2022; 46:6623663. [PMID: 35772001 PMCID: PMC9629498 DOI: 10.1093/femsre/fuac030] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 06/01/2022] [Accepted: 06/28/2022] [Indexed: 01/09/2023] Open
Abstract
The heterogeneity of bacterial growth and replicative rates within a population was proposed a century ago notably to explain the presence of bacterial persisters. The term "growth rate" at the single-cell level corresponds to the increase in size or mass of an individual bacterium while the "replicative rate" refers to its division capacity within a defined temporality. After a decades long hiatus, recent technical innovative approaches allow population growth and replicative rates heterogeneity monitoring at the single-cell level resuming in earnest. Among these techniques, the oldest and widely used is time-lapse microscopy, most recently combined with microfluidics. We also discuss recent fluorescence dilution methods informing only on replicative rates and best suited. Some new elegant single cell methods so far only sporadically used such as buoyant mass measurement and stable isotope probing have emerged. Overall, such tools are widely used to investigate and compare the growth and replicative rates of bacteria displaying drug-persistent behaviors to that of bacteria growing in specific ecological niches or collected from patients. In this review, we describe the current methods available, discussing both the type of queries these have been used to answer and the specific strengths and limitations of each method.
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Affiliation(s)
- Florian C Marro
- Evotec ID Lyon, In Vitro Biology, Infectious Diseases and Antibacterials Unit, Gerland, 69007 Lyon, France,CIRI – Centre International de Recherche en Infectiologie, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, F-69007 Lyon, France
| | - Frédéric Laurent
- CIRI – Centre International de Recherche en Infectiologie, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, F-69007 Lyon, France,Institut des Sciences Pharmaceutiques et Biologiques (ISPB), Université Claude Bernard Lyon 1, Lyon, France,Centre de Référence pour la prise en charge des Infections ostéo-articulaires complexes (CRIOAc Lyon; www.crioac-lyon.fr), Hospices Civils de Lyon, Lyon, France,Laboratoire de bactériologie, Institut des Agents Infectieux, French National Reference Center for Staphylococci, Hospices Civils de Lyon, Lyon, France
| | - Jérôme Josse
- CIRI – Centre International de Recherche en Infectiologie, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, F-69007 Lyon, France,Institut des Sciences Pharmaceutiques et Biologiques (ISPB), Université Claude Bernard Lyon 1, Lyon, France,Centre de Référence pour la prise en charge des Infections ostéo-articulaires complexes (CRIOAc Lyon; www.crioac-lyon.fr), Hospices Civils de Lyon, Lyon, France
| | - Ariel J Blocker
- Corresponding author. Evotec ID Lyon, In Vitro Biology, Infectious Diseases and Antibacterials Unit, France. E-mail:
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18
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Kriel NL, Newton-Foot M, Bennion OT, Aldridge BB, Mehaffy C, Belisle JT, Walzl G, Warren RM, Sampson SL, Gey van Pittius NC. Localization of EccA 3 at the growing pole in Mycobacterium smegmatis. BMC Microbiol 2022; 22:140. [PMID: 35590245 PMCID: PMC9118679 DOI: 10.1186/s12866-022-02554-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 05/09/2022] [Indexed: 11/30/2022] Open
Abstract
Background Bacteria require specialized secretion systems for the export of molecules into the extracellular space to modify their environment and scavenge for nutrients. The ESX-3 secretion system is required by mycobacteria for iron homeostasis. The ESX-3 operon encodes for one cytoplasmic component (EccA3) and five membrane components (EccB3 – EccE3 and MycP3). In this study we sought to identify the sub-cellular location of EccA3 of the ESX-3 secretion system in mycobacteria. Results Fluorescently tagged EccA3 localized to a single pole in the majority of Mycobacterium smegmatis cells and time-lapse fluorescent microscopy identified this pole as the growing pole. Deletion of ESX-3 did not prevent polar localization of fluorescently tagged EccA3, suggesting that EccA3 unipolar localization is independent of other ESX-3 components. Affinity purification - mass spectrometry was used to identify EccA3 associated proteins which may contribute to the localization of EccA3 at the growing pole. EccA3 co-purified with fatty acid metabolism proteins (FAS, FadA3, KasA and KasB), mycolic acid synthesis proteins (UmaA, CmaA1), cell division proteins (FtsE and FtsZ), and cell shape and cell cycle proteins (MurS, CwsA and Wag31). Secretion system related proteins Ffh, SecA1, EccA1, and EspI were also identified. Conclusions Time-lapse microscopy demonstrated that EccA3 is located at the growing pole in M. smegmatis. The co-purification of EccA3 with proteins known to be required for polar growth, mycolic acid synthesis, the Sec secretion system (SecA1), and the signal recognition particle pathway (Ffh) also suggests that EccA3 is located at the site of active cell growth. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-022-02554-6.
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Affiliation(s)
- Nastassja L Kriel
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
| | - Mae Newton-Foot
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Owen T Bennion
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, 02111, USA
| | - Bree B Aldridge
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, 02111, USA
| | - Carolina Mehaffy
- Mycobacteria Research Laboratories, Department of Microbiology Immunology and Pathology, Colorado State University, Fort Collins, CO, 80523, USA
| | - John T Belisle
- Mycobacteria Research Laboratories, Department of Microbiology Immunology and Pathology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Gerhard Walzl
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Robin M Warren
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Samantha L Sampson
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Nico C Gey van Pittius
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
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19
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Urbaniec J, Xu Y, Hu Y, Hingley-Wilson S, McFadden J. Phenotypic heterogeneity in persisters: a novel 'hunker' theory of persistence. FEMS Microbiol Rev 2022; 46:fuab042. [PMID: 34355746 PMCID: PMC8767447 DOI: 10.1093/femsre/fuab042] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 08/04/2021] [Indexed: 12/11/2022] Open
Abstract
Persistence has been linked to treatment failure since its discovery over 70 years ago and understanding formation, nature and survival of this key antibiotic refractory subpopulation is crucial to enhancing treatment success and combatting the threat of antimicrobial resistance (AMR). The term 'persistence' is often used interchangeably with other terms such as tolerance or dormancy. In this review we focus on 'antibiotic persistence' which we broadly define as a feature of a subpopulation of bacterial cells that possesses the non-heritable character of surviving exposure to one or more antibiotics; and persisters as cells that possess this characteristic. We discuss novel molecular mechanisms involved in persister cell formation, as well as environmental factors which can contribute to increased antibiotic persistence in vivo, highlighting recent developments advanced by single-cell studies. We also aim to provide a comprehensive model of persistence, the 'hunker' theory which is grounded in intrinsic heterogeneity of bacterial populations and a myriad of 'hunkering down' mechanisms which can contribute to antibiotic survival of the persister subpopulation. Finally, we discuss antibiotic persistence as a 'stepping-stone' to AMR and stress the urgent need to develop effective anti-persister treatment regimes to treat this highly clinically relevant bacterial sub-population.
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Affiliation(s)
- J Urbaniec
- Department of Microbial Sciences and University of Surrey, Guildford, Surrey, GU27XH, UK
| | - Ye Xu
- Department of Microbial Sciences and University of Surrey, Guildford, Surrey, GU27XH, UK
| | - Y Hu
- Farnborough Sensonic limited, Farnborough road, GU14 7NA, UK
| | - S Hingley-Wilson
- Department of Microbial Sciences and University of Surrey, Guildford, Surrey, GU27XH, UK
| | - J McFadden
- Department of Microbial Sciences and University of Surrey, Guildford, Surrey, GU27XH, UK
- Quantum biology doctoral training centre, University of Surrey, Guildford, Surrey, GU27XH, UK
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20
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Emerging technologies and infection models in cellular microbiology. Nat Commun 2021; 12:6764. [PMID: 34799563 PMCID: PMC8604907 DOI: 10.1038/s41467-021-26641-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 10/18/2021] [Indexed: 01/09/2023] Open
Abstract
The field of cellular microbiology, rooted in the co-evolution of microbes and their hosts, studies intracellular pathogens and their manipulation of host cell machinery. In this review, we highlight emerging technologies and infection models that recently promoted opportunities in cellular microbiology. We overview the explosion of microscopy techniques and how they reveal unprecedented detail at the host-pathogen interface. We discuss the incorporation of robotics and artificial intelligence to image-based screening modalities, biochemical mapping approaches, as well as dual RNA-sequencing techniques. Finally, we describe chips, organoids and animal models used to dissect biophysical and in vivo aspects of the infection process. As our knowledge of the infected cell improves, cellular microbiology holds great promise for development of anti-infective strategies with translational applications in human health.
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21
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Fluorescence Imaging-Based Discovery of Membrane Domain-Associated Proteins in Mycobacterium smegmatis. J Bacteriol 2021; 203:e0041921. [PMID: 34516286 DOI: 10.1128/jb.00419-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Mycobacteria spatially organize their plasma membrane, and many enzymes involved in envelope biosynthesis associate with a membrane compartment termed the intracellular membrane domain (IMD). The IMD is concentrated in the polar regions of growing cells and becomes less polarized under nongrowing conditions. Because mycobacteria elongate from the poles, the observed polar localization of the IMD during growth likely supports the localized biosynthesis of envelope components. While we have identified more than 300 IMD-associated proteins by proteomic analyses, only a few of these have been verified by independent experimental methods. Furthermore, some IMD-associated proteins may have escaped proteomic identification and remain to be identified. Here, we visually screened an arrayed library of 523 Mycobacterium smegmatis strains, each producing a Dendra2-FLAG-tagged recombinant protein. We identified 29 fusion proteins that showed polar fluorescence patterns characteristic of IMD proteins. Twenty of these had previously been suggested to localize to the IMD based on proteomic data. Of the nine remaining IMD candidate proteins, three were confirmed by biochemical methods to be associated with the IMD. Taken together, this new colocalization strategy is effective in verifying the IMD association of proteins found by proteomic analyses while facilitating the discovery of additional IMD-associated proteins. IMPORTANCE The intracellular membrane domain (IMD) is a membrane subcompartment found in Mycobacterium smegmatis cells. Proteomic analysis of purified IMD identified more than 300 proteins, including enzymes involved in cell envelope biosynthesis. However, proteomics on its own is unlikely to detect every IMD-associated protein because of technical and biological limitations. Here, we describe fluorescent protein colocalization as an alternative, independent approach. Using a combination of fluorescence microscopy, proteomics, and subcellular fractionation, we identified three new proteins associated with the IMD. Such a robust method to rigorously define IMD proteins will benefit future investigations to decipher the synthesis, maintenance, and functions of this membrane domain and help delineate a more general mechanism of subcellular protein localization in mycobacteria.
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22
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Meunier A, Cornet F, Campos M. Bacterial cell proliferation: from molecules to cells. FEMS Microbiol Rev 2021; 45:5912836. [PMID: 32990752 PMCID: PMC7794046 DOI: 10.1093/femsre/fuaa046] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 09/10/2020] [Indexed: 12/11/2022] Open
Abstract
Bacterial cell proliferation is highly efficient, both because bacteria grow fast and multiply with a low failure rate. This efficiency is underpinned by the robustness of the cell cycle and its synchronization with cell growth and cytokinesis. Recent advances in bacterial cell biology brought about by single-cell physiology in microfluidic chambers suggest a series of simple phenomenological models at the cellular scale, coupling cell size and growth with the cell cycle. We contrast the apparent simplicity of these mechanisms based on the addition of a constant size between cell cycle events (e.g. two consecutive initiation of DNA replication or cell division) with the complexity of the underlying regulatory networks. Beyond the paradigm of cell cycle checkpoints, the coordination between the DNA and division cycles and cell growth is largely mediated by a wealth of other mechanisms. We propose our perspective on these mechanisms, through the prism of the known crosstalk between DNA replication and segregation, cell division and cell growth or size. We argue that the precise knowledge of these molecular mechanisms is critical to integrate the diverse layers of controls at different time and space scales into synthetic and verifiable models.
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Affiliation(s)
- Alix Meunier
- Centre de Biologie Intégrative de Toulouse (CBI Toulouse), Laboratoire de Microbiologie et Génétique Moléculaires (LMGM), Université de Toulouse, UPS, CNRS, IBCG, 165 rue Marianne Grunberg-Manago, 31062 Toulouse, France
| | - François Cornet
- Centre de Biologie Intégrative de Toulouse (CBI Toulouse), Laboratoire de Microbiologie et Génétique Moléculaires (LMGM), Université de Toulouse, UPS, CNRS, IBCG, 165 rue Marianne Grunberg-Manago, 31062 Toulouse, France
| | - Manuel Campos
- Centre de Biologie Intégrative de Toulouse (CBI Toulouse), Laboratoire de Microbiologie et Génétique Moléculaires (LMGM), Université de Toulouse, UPS, CNRS, IBCG, 165 rue Marianne Grunberg-Manago, 31062 Toulouse, France
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23
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Herricks T, Donczew M, Sherman DR, Aitchison JD. ODELAM: Rapid Sequence-independent Detection of Drug Resistance in Mycobacterium tuberculosis Isolates. Bio Protoc 2021; 11:e4027. [PMID: 34150934 DOI: 10.21769/bioprotoc.4027] [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: 10/30/2020] [Revised: 02/23/2021] [Accepted: 03/31/2021] [Indexed: 11/02/2022] Open
Abstract
Antimicrobial-resistant Mycobacterium tuberculosis (Mtb) causes over 200,000 deaths globally each year. Current assays of antimicrobial resistance require knowledge of the mutations that confer drug resistance or long periods of culture time to test growth under drug pressure. We present ODELAM (One-cell Doubling Evaluation of Living Arrays of Mycobacterium), a time-lapse microscopy-based method that observes individual cells growing into microcolonies. This protocol describes sample and media preparation and contains instructions for assembling the ODELAM sample chamber. The ODELAM sample chamber is designed to provide a controlled environment to safely observe the growth of Mtb by time-lapse microscopy on an inverted wide-field microscope. A brief description of the ODELAM software is also provided here. ODELAM tracks up to 1500 colony forming units per region of interest and can observe up to 96 regions for up to seven days in a single experiment. This technique allows the quantification of population heterogeneity. ODELAM enables rapid quantitative measurements of growth kinetics in as few as 30 h under a wide variety of environmental conditions. Graphic abstract: Schematic representation of the ODELAM platform.
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Affiliation(s)
- Thurston Herricks
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, USA
| | | | - David R Sherman
- Department of Microbiology, University of Washington, Seattle, USA
| | - John D Aitchison
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, USA.,Department of Pediatrics, University of Washington, Seattle, USA
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24
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Abstract
Mycobacteria have unique cell envelopes, surface properties, and growth dynamics, which all play a part in the ability of these important pathogens to infect, evade host immunity, disseminate, and resist antibiotic challenges. Recent atomic force microscopy (AFM) studies have brought new insights into the nanometer-scale ultrastructural, adhesive, and mechanical properties of mycobacteria. The molecular forces with which mycobacterial adhesins bind to host factors, like heparin and fibronectin, and the hydrophobic properties of the mycomembrane have been unraveled by AFM force spectroscopy studies. Real-time correlative AFM and fluorescence imaging have delineated a complex interplay between surface ultrastructure, tensile stresses within the cell envelope, and cellular processes leading to division. The unique capabilities of AFM, which include subdiffraction-limit topographic imaging and piconewton force sensitivity, have great potential to resolve important questions that remain unanswered on the molecular interactions, surface properties, and growth dynamics of this important class of pathogens.
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25
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Wang R, Ehrt S. Rv0954 Is a Member of the Mycobacterial Cell Division Complex. Front Microbiol 2021; 12:626461. [PMID: 33959103 PMCID: PMC8093794 DOI: 10.3389/fmicb.2021.626461] [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: 11/05/2020] [Accepted: 03/15/2021] [Indexed: 11/13/2022] Open
Abstract
Proper control of cell division in the intracellular pathogen Mycobacterium tuberculosis is central to its growth, survival, pathogenesis, and resistance to antibiotics. Nevertheless, the divisome components and mechanisms by which mycobacteria regulate their cell cycle are not entirely understood. Here we demonstrate that the previously uncharacterized Rv0954 protein localizes to the mid-cell during cell division and interacts with the division-related proteins LamA, PbpA, and PknH. Deletion of rv0954 did not result in alterations in cell morphology or sensitivity to cell wall-targeting antibiotics but transposon mutagenesis demonstrated genetic interactions with genes related to cell division. This work suggests that Rv0954 participates in cell division and reveals potential components of the mycobacterial divisome for future investigation.
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Affiliation(s)
- Ruojun Wang
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, United States
| | - Sabine Ehrt
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, United States
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26
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Lequieu J, Magenau AJD. Reaction-induced phase transitions with block copolymers in solution and bulk. Polym Chem 2021. [DOI: 10.1039/d0py00722f] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Reaction-induced phase transitions use chemical reactions to drive macromolecular organisation and self-assembly. This review highlights significant and recent advancements in this burgeoning field.
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Affiliation(s)
- Joshua Lequieu
- Department of Chemical and Biological Engineering
- Drexel University
- Philadelphia
- USA
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27
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Yamada H, Chikamatsu K, Aono A, Murata K, Miyazaki N, Kayama Y, Bhatt A, Fujiwara N, Maeda S, Mitarai S. Fundamental Cell Morphologies Examined With Cryo-TEM of the Species in the Novel Five Genera Robustly Correlate With New Classification in Family Mycobacteriaceae. Front Microbiol 2020; 11:562395. [PMID: 33304323 PMCID: PMC7701246 DOI: 10.3389/fmicb.2020.562395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 10/12/2020] [Indexed: 11/25/2022] Open
Abstract
A recent study proposed the novel classification of the family Mycobacteriaceae based on the genome analysis of core proteins in 150 Mycobacterium species. The results from these analyses supported the existence of five distinct monophyletic groups within the genus Mycobacterium. That is, Mycobacterium has been divided into two novel genera for rapid grower Mycobacteroides and Mycolicibacterium, and into three genera for slow grower Mycolicibacter, Mycolicibacillus, and an emended genus Mycobacterium, which include all the major human pathogens. Here, cryo-TEM examinations of 1,816 cells of 31 species (34 strains) belonging to the five novel genera were performed. The fundamental morphological properties of every single cell, such as cell diameter, cell length, cell perimeter, cell circularity, and aspect ratio were measured and compared between these genera. In 50 comparisons on the five parameters between any two genera, only five comparisons showed “non-significant” differences. That is, there are non-significant differences between slow grower genus Mycolicibacillus and genus Mycobacterium in average cell diameter (p = 0.15), between rapid grower genus Mycobacteroides and slow grower genus Mycobacterium in average cell length (p > 0.24), between genus Mycobacteroides and genus Mycobacterium (p > 0.68) and between genus Mycolicibacter and genus Mycolicibacillus (p > 0.11) in average cell perimeter, and between genus Mycolicibacterium and genus Mycobacterium in circularity (p > 0.73). The other 45 comparisons showed significant differences between the genera. Genus Mycobacteroides showed the longest average cell diameter, whereas the genus Mycolicibacter showed the shortest average diameter. Genus Mycolicibacterium showed the most extended average cell length, perimeter, and aspect ratio, whereas the genus Mycolicibacillus showed the shortest average cell length, perimeter, and aspect ratio. Genus Mycolicibacillus showed the highest average cell circularity, whereas genus Mycobacterium showed the lowest average cell circularity. These fundamental morphological data strongly support the new classification in the family Mycobacteriaceae, and this classification is rational and effective in the study of the members of the family Mycobacteriaceae. Because both the genus Mycolicibacterium and the genus Mycobacterium contain many species and showed larger significant standard deviations in every parameter, these genera may be divided into novel genera which show common genotype and phenotypes in morphology and pathogenicity.
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Affiliation(s)
- Hiroyuki Yamada
- Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Kinuyo Chikamatsu
- Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Akio Aono
- Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Kazuyoshi Murata
- Supportive Center for Brain Research, National Institute for Physiological Science, Okazaki, Japan
| | - Naoyuki Miyazaki
- Supportive Center for Brain Research, National Institute for Physiological Science, Okazaki, Japan.,Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Japan
| | | | - Apoorva Bhatt
- School of Biosciences and Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Nagatoshi Fujiwara
- Department of Food and Nutrition, Faculty of Contemporary Human Life Science, Tezukayama University, Nara, Japan
| | - Shinji Maeda
- Department of Pharmacy, Faculty of Pharmaceutical Science, Hokkaido University of Science, Sapporo, Japan
| | - Satoshi Mitarai
- Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan.,Department of Basic Mycobacteriology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
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28
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Bandekar AC, Subedi S, Ioerger TR, Sassetti CM. Cell-Cycle-Associated Expression Patterns Predict Gene Function in Mycobacteria. Curr Biol 2020; 30:3961-3971.e6. [PMID: 32916109 PMCID: PMC7578119 DOI: 10.1016/j.cub.2020.07.070] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/26/2020] [Accepted: 07/22/2020] [Indexed: 12/20/2022]
Abstract
Although the major events in prokaryotic cell cycle progression are likely to be coordinated with transcriptional and metabolic changes, these processes remain poorly characterized. Unlike many rapidly growing bacteria, DNA replication and cell division are temporally resolved in mycobacteria, making these slow-growing organisms a potentially useful system to investigate the prokaryotic cell cycle. To determine whether cell-cycle-dependent gene regulation occurs in mycobacteria, we characterized the temporal changes in the transcriptome of synchronously replicating populations of Mycobacterium tuberculosis (Mtb). By enriching for genes that display a sinusoidal expression pattern, we discover 485 genes that oscillate with a period consistent with the cell cycle. During cytokinesis, the timing of gene induction could be used to predict the timing of gene function, as mRNA abundance was found to correlate with the order in which proteins were recruited to the developing septum. Similarly, the expression pattern of primary metabolic genes could be used to predict the relative importance of these pathways for different cell cycle processes. Pyrimidine synthetic genes peaked during DNA replication, and their depletion caused a filamentation phenotype that phenocopied defects in this process. In contrast, the inosine monophasphate dehydrogenase dedicated to guanosine synthesis, GuaB2, displayed the opposite expression pattern and its depletion perturbed septation. Together, these data imply obligate coordination between primary metabolism and cell division and identify periodically regulated genes that can be related to specific cell biological functions.
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Affiliation(s)
- Aditya C Bandekar
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Sishir Subedi
- Department of Computer Science and Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Thomas R Ioerger
- Department of Computer Science and Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Christopher M Sassetti
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA.
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29
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Singhi D, Srivastava P. How similar or dissimilar cells are produced by bacterial cell division? Biochimie 2020; 176:71-84. [DOI: 10.1016/j.biochi.2020.06.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 10/24/2022]
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30
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Parbhoo T, Sampson SL, Mouton JM. Recent Developments in the Application of Flow Cytometry to Advance our Understanding of Mycobacterium tuberculosis Physiology and Pathogenesis. Cytometry A 2020; 97:683-693. [PMID: 32437069 PMCID: PMC7496436 DOI: 10.1002/cyto.a.24030] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 04/18/2020] [Accepted: 04/21/2020] [Indexed: 12/16/2022]
Abstract
The ability of the bacterial pathogen Mycobacterium tuberculosis to adapt and survive within human cells to disseminate to other individuals and cause active disease is poorly understood. Research supports that as M. tuberculosis adapts to stressors encountered in the host, it exhibits variable physiological and metabolic states that are time and niche-dependent. Challenges associated with effective treatment and eradication of tuberculosis (TB) are in part attributed to our lack of understanding of these different mycobacterial phenotypes. This is mainly due to a lack of suitable tools to effectively identify/detect heterogeneous bacterial populations, which may include small, difficult-to-culture subpopulations. Importantly, flow cytometry allows rapid and affordable multiparametric measurements of physical and chemical characteristics of single cells, without the need to preculture cells. Here, we summarize current knowledge of flow cytometry applications that have advanced our understanding of the physiology of M. tuberculosis during TB disease. Specifically, we review how host-associated stressors influence bacterial characteristics such as metabolic activity, membrane potential, redox status and the mycobacterial cell wall. Further, we highlight that flow cytometry offers unprecedented opportunities for insight into bacterial population heterogeneity, which is increasingly appreciated as an important determinant of disease outcome. © 2020 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.
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Affiliation(s)
- Trisha Parbhoo
- NRF‐DST Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health SciencesStellenbosch UniversityCape TownSouth Africa
| | - Samantha L. Sampson
- NRF‐DST Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health SciencesStellenbosch UniversityCape TownSouth Africa
| | - Jacoba M. Mouton
- NRF‐DST Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health SciencesStellenbosch UniversityCape TownSouth Africa
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31
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A biphasic growth model for cell pole elongation in mycobacteria. Nat Commun 2020; 11:452. [PMID: 31974342 PMCID: PMC6978421 DOI: 10.1038/s41467-019-14088-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 12/10/2019] [Indexed: 12/02/2022] Open
Abstract
Mycobacteria grow by inserting new cell wall material in discrete zones at the cell poles. This pattern implies that polar growth zones must be assembled de novo at each division, but the mechanisms that control the initiation of new pole growth are unknown. Here, we combine time-lapse optical and atomic force microscopy to measure single-cell pole growth in mycobacteria with nanometer-scale precision. We show that single-cell growth is biphasic due to a lag phase of variable duration before the new pole transitions from slow to fast growth. This transition and cell division are independent events. The difference between the lag and interdivision times determines the degree of single-cell growth asymmetry, which is high in fast-growing species and low in slow-growing species. We propose a biphasic growth model that is distinct from previous unipolar and bipolar models and resembles “new end take off” (NETO) dynamics of polar growth in fission yeast. Mycobacteria grow by inserting new cell wall material at the cell poles. Here, Hannebelle et al. combine time-lapse optical and atomic force microscopy to show that single-cell growth is biphasic due to a lag phase of variable duration before the new pole transitions from slow to fast growth.
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32
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Odermatt PD, Hannebelle MTM, Eskandarian HA, Nievergelt AP, McKinney JD, Fantner GE. Overlapping and essential roles for molecular and mechanical mechanisms in mycobacterial cell division. NATURE PHYSICS 2020; 16:57-62. [PMID: 31921326 PMCID: PMC6952280 DOI: 10.1038/s41567-019-0679-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 09/04/2019] [Indexed: 05/30/2023]
Abstract
Mechanisms to control cell division are essential for cell proliferation and survival 1. Bacterial cell growth and division require the coordinated activity of peptidoglycan synthases and hydrolytic enzymes 2-4 to maintain mechanical integrity of the cell wall 5. Recent studies suggest that cell separation is governed by mechanical forces 6,7. How mechanical forces interact with molecular mechanisms to control bacterial cell division in space and time is poorly understood. Here, we use a combination of atomic force microscope (AFM) imaging, nanomechanical mapping, and nanomanipulation to show that enzymatic activity and mechanical forces serve overlapping and essential roles in mycobacterial cell division. We find that mechanical stress gradually accumulates in the cell wall concentrated at the future division site, culminating in rapid (millisecond) cleavage of nascent sibling cells. Inhibiting cell wall hydrolysis delays cleavage; conversely, locally increasing cell wall stress causes instantaneous and premature cleavage. Cells deficient in peptidoglycan hydrolytic activity fail to locally decrease their cell wall strength and undergo natural cleavage, instead forming chains of non-growing cells. Cleavage of these cells can be mechanically induced by local application of stress with AFM. These findings establish a direct link between actively controlled molecular mechanisms and passively controlled mechanical forces in bacterial cell division.
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Affiliation(s)
- Pascal D. Odermatt
- Laboratory for Bio- and Nano-Instrumentation, School of Engineering, Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland
| | - Mélanie T. M. Hannebelle
- Laboratory for Bio- and Nano-Instrumentation, School of Engineering, Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland
- Laboratory of Microbiology and Microtechnology, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland
| | - Haig A. Eskandarian
- Laboratory for Bio- and Nano-Instrumentation, School of Engineering, Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland
- Laboratory of Microbiology and Microtechnology, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland
| | - Adrian P. Nievergelt
- Laboratory for Bio- and Nano-Instrumentation, School of Engineering, Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland
| | - John D. McKinney
- Laboratory of Microbiology and Microtechnology, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland
| | - Georg E. Fantner
- Laboratory for Bio- and Nano-Instrumentation, School of Engineering, Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland
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33
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Choukate K, Gupta A, Basu B, Virk K, Ganguli M, Chaudhuri B. Higher order assembling of the mycobacterial polar growth factor DivIVA/Wag31. J Struct Biol 2019; 209:107429. [PMID: 31778770 DOI: 10.1016/j.jsb.2019.107429] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 10/04/2019] [Accepted: 11/21/2019] [Indexed: 12/26/2022]
Abstract
DivIVA or Wag31, which is an essential pole organizing protein in mycobacteria, can self-assemble at the negatively curved side of the membrane at the growing pole to form a higher order structural scaffold for maintaining cellular morphology and localizing various target proteins for cell-wall biogenesis. The structural organization of polar scaffold formed by polymerization of coiled-coil rich Wag31, which is implicated in the anti-tubercular activities of amino-pyrimidine sulfonamides, remains to be determined. A single-site phosphorylation in Wag31 regulates peptidoglycan biosynthesis in mycobacteria. We report biophysical characterizations of filaments formed by mycobacterial Wag31 using circular dichroism, atomic force microscopy and small angle solution X-ray scattering. Atomic force microscopic images of the wild-type, a phospho-mimetic (T73E) and a phospho-ablative (T73A) form of Wag31 show mostly linear filament formation with occasional curving, kinking and apparent branching. Solution X-ray scattering data indicates that the phospho-mimetic forms of the Wag31 polymers are on average more compact than their phospho-ablative counterparts, which is likely due to the extent of bending/branching. Observed structural features in this first view of Wag31 filaments suggest a basis for higher order Wag31 scaffold formation at the pole.
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Affiliation(s)
- Komal Choukate
- CSIR Institute of Microbial Technology, Chandigarh, India
| | - Aanchal Gupta
- CSIR Institute of Genomics and Integrative Biology, New Delhi, India; Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India
| | - Brohmomoy Basu
- CSIR Institute of Microbial Technology, Chandigarh, India
| | - Karman Virk
- CSIR Institute of Microbial Technology, Chandigarh, India
| | - Munia Ganguli
- CSIR Institute of Genomics and Integrative Biology, New Delhi, India; Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India
| | - Barnali Chaudhuri
- CSIR Institute of Microbial Technology, Chandigarh, India; Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India.
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34
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Bumann D, Fanous J, Li J, Goormaghtigh F. Antibiotic chemotherapy against heterogeneous pathogen populations in complex host tissues. F1000Res 2019; 8. [PMID: 31737252 PMCID: PMC6807158 DOI: 10.12688/f1000research.19441.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/15/2019] [Indexed: 12/20/2022] Open
Abstract
Antibiotic chemotherapy effectively cures many infections caused by susceptible bacterial pathogens. However, in some cases, even extended treatment duration does not completely eradicate the pathogenic bacteria from host tissues. A common model for underlying mechanisms assumes the stochastic formation of bacterial persisters similar to observations in laboratory cultures. However, alternative explanations related to the complexity of infected host tissues could also be relevant. We discuss several of these aspects and emphasize the need for integrated analysis as a basis for new control strategies.
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Affiliation(s)
- Dirk Bumann
- Research Area Infection Biology, Biozentrum, University of Basel, Basel, CH-4056, Switzerland
| | - Joseph Fanous
- Research Area Infection Biology, Biozentrum, University of Basel, Basel, CH-4056, Switzerland
| | - Jiagui Li
- Research Area Infection Biology, Biozentrum, University of Basel, Basel, CH-4056, Switzerland
| | - Frédéric Goormaghtigh
- Research Area Infection Biology, Biozentrum, University of Basel, Basel, CH-4056, Switzerland
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35
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Manina G, Griego A, Singh LK, McKinney JD, Dhar N. Preexisting variation in DNA damage response predicts the fate of single mycobacteria under stress. EMBO J 2019; 38:e101876. [PMID: 31583725 DOI: 10.15252/embj.2019101876] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 08/06/2019] [Accepted: 09/16/2019] [Indexed: 11/09/2022] Open
Abstract
Clonal microbial populations are inherently heterogeneous, and this diversification is often considered as an adaptation strategy. In clinical infections, phenotypic diversity is found to be associated with drug tolerance, which in turn could evolve into genetic resistance. Mycobacterium tuberculosis, which ranks among the top ten causes of mortality with high incidence of drug-resistant infections, exhibits considerable phenotypic diversity. In this study, we quantitatively analyze the cellular dynamics of DNA damage responses in mycobacteria using microfluidics and live-cell fluorescence imaging. We show that individual cells growing under optimal conditions experience sporadic DNA-damaging events manifested by RecA expression pulses. Single-cell responses to these events occur as transient pulses of fluorescence expression, which are dependent on the gene-network structure but are triggered by extrinsic signals. We demonstrate that preexisting subpopulations, with discrete levels of DNA damage response, are associated with differential susceptibility to fluoroquinolones. Our findings reveal that the extent of DNA integrity prior to drug exposure impacts the drug activity against mycobacteria, with conceivable therapeutic implications.
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Affiliation(s)
- Giulia Manina
- Microbial Individuality and Infection Group, Cell Biology and Infection Department, Institut Pasteur, Paris, France.,School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
| | - Anna Griego
- Microbial Individuality and Infection Group, Cell Biology and Infection Department, Institut Pasteur, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Lalit Kumar Singh
- Microbial Individuality and Infection Group, Cell Biology and Infection Department, Institut Pasteur, Paris, France
| | - John D McKinney
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
| | - Neeraj Dhar
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
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36
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Watching DNA Replication Inhibitors in Action: Exploiting Time-Lapse Microfluidic Microscopy as a Tool for Target-Drug Interaction Studies in Mycobacterium. Antimicrob Agents Chemother 2019; 63:AAC.00739-19. [PMID: 31383667 PMCID: PMC6761567 DOI: 10.1128/aac.00739-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/26/2019] [Indexed: 01/08/2023] Open
Abstract
Spreading resistance to antibiotics and the emergence of multidrug-resistant strains have become frequent in many bacterial species, including mycobacteria, which are the causative agents of severe diseases and which have profound impacts on global health. Here, we used a system of microfluidics, fluorescence microscopy, and target-tagged fluorescent reporter strains of Mycobacterium smegmatis to perform real-time monitoring of replisome and chromosome dynamics following the addition of replication-altering drugs (novobiocin, nalidixic acid, and griselimycin) at the single-cell level. We found that novobiocin stalled replication forks and caused relaxation of the nucleoid and that nalidixic acid triggered rapid replisome collapse and compaction of the nucleoid, while griselimycin caused replisome instability, with the subsequent overinitiation of chromosome replication and overrelaxation of the nucleoid. In addition to study target-drug interactions, our system also enabled us to observe how the tested antibiotics affected the physiology of mycobacterial cells (i.e., growth, chromosome segregation, etc.).
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37
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Abstract
How do mycobacteria divide? Cell division has been studied extensively in the model rod-shaped bacteria Escherichia coli and Bacillus subtilis, but much less is understood about cell division in mycobacteria, a genus that includes the major human pathogens M. tuberculosis and M. leprae. In general, bacterial cell division requires the concerted effort of many proteins in both space and time to elongate the cell, replicate and segregate the chromosome, and construct and destruct the septum - processes which result in the creation of two new daughter cells. Here, we describe these distinct stages of cell division in B. subtilis and follow with the current knowledge in mycobacteria. As will become apparent, there are many differences between mycobacteria and B. subtilis in terms of both the broad outline of cell division and the molecular details. So, while the fundamental challenge of spatially and temporally organizing cell division is shared between these rod-shaped bacteria, they have solved these challenges in often vastly different ways.
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38
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Si F, Le Treut G, Sauls JT, Vadia S, Levin PA, Jun S. Mechanistic Origin of Cell-Size Control and Homeostasis in Bacteria. Curr Biol 2019; 29:1760-1770.e7. [PMID: 31104932 DOI: 10.1016/j.cub.2019.04.062] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/18/2019] [Accepted: 04/24/2019] [Indexed: 02/06/2023]
Abstract
Evolutionarily divergent bacteria share a common phenomenological strategy for cell-size homeostasis under steady-state conditions. In the presence of inherent physiological stochasticity, cells following this "adder" principle gradually return to their steady-state size by adding a constant volume between birth and division, regardless of their size at birth. However, the mechanism of the adder has been unknown despite intense efforts. In this work, we show that the adder is a direct consequence of two general processes in biology: (1) threshold-accumulation of initiators and precursors required for cell division to a respective fixed number-and (2) balanced biosynthesis-maintenance of their production proportional to volume growth. This mechanism is naturally robust to static growth inhibition but also allows us to "reprogram" cell-size homeostasis in a quantitatively predictive manner in both Gram-negative Escherichia coli and Gram-positive Bacillus subtilis. By generating dynamic oscillations in the concentration of the division protein FtsZ, we were able to oscillate cell size at division and systematically break the adder. In contrast, periodic induction of replication initiator protein DnaA caused oscillations in cell size at initiation but did not alter division size or the adder. Finally, we were able to restore the adder phenotype in slow-growing E. coli, the only known steady-state growth condition wherein E. coli significantly deviates from the adder, by repressing active degradation of division proteins. Together, these results show that cell division and replication initiation are independently controlled at the gene-expression level and that division processes exclusively drive cell-size homeostasis in bacteria. VIDEO ABSTRACT.
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Affiliation(s)
- Fangwei Si
- Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Guillaume Le Treut
- Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA
| | - John T Sauls
- Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Stephen Vadia
- Department of Biology, Washington University in St. Louis, Saint Louis, MO 63130, USA
| | - Petra Anne Levin
- Department of Biology, Washington University in St. Louis, Saint Louis, MO 63130, USA
| | - Suckjoon Jun
- Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA; Section of Molecular Biology, Division of Biology, University of California, San Diego, La Jolla, CA 92093, USA.
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39
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Levin PA, Taheri-Araghi S. One is Nothing without the Other: Theoretical and Empirical Analysis of Cell Growth and Cell Cycle Progression. J Mol Biol 2019; 431:2061-2067. [PMID: 31026450 DOI: 10.1016/j.jmb.2019.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/25/2019] [Accepted: 04/02/2019] [Indexed: 11/19/2022]
Abstract
Small, fast-growing bacteria make ideal subjects for genetic and quantitative analysis alike. Long the darling of theoreticians, efforts to understand the relationship between cell growth and cell cycle progression in bacterial systems have been propelled by modelers and empiricist in equal measure. Taking a historical approach, here we break down early work in this area, the impact it had on how the bacterial cell cycle is understood and interrogated, and changes brought by the advent of high-throughput techniques for the analysis of individual bacterial cells in culture.
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Affiliation(s)
- Petra Anne Levin
- Department of Biology, Washington University in St. Louis, MO 63130, United States.
| | - Sattar Taheri-Araghi
- Department of Physics and Astronomy, California State University, Northridge, CA 91311, United States.
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40
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Ealand CS, Asmal R, Mashigo L, Campbell L, Kana BD. Characterization of putative DD-carboxypeptidase-encoding genes in Mycobacterium smegmatis. Sci Rep 2019; 9:5194. [PMID: 30914728 PMCID: PMC6435803 DOI: 10.1038/s41598-019-41001-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 02/22/2019] [Indexed: 01/21/2023] Open
Abstract
Penicillin binding proteins (PBPs) are the target of numerous antimicrobial agents that disrupt bacterial cell wall synthesis. In mycobacteria, cell elongation occurs through insertion of nascent cell wall material in the sub-polar region, a process largely driven by High Molecular Weight PBPs. In contrast, the function of DD-carboxypeptidases (DD-CPases), which are Low Molecular Weight Class 1C PBPs, in mycobacteria remains poorly understood. Mycobacterium smegmatis encodes four putative DD-CPase homologues, which display homology to counterparts in Escherichia coli. Herein, we demonstrate that these are expressed in varying abundance during growth. Deletion of MSMEG_1661, MSMEG_2433 or MSMEG_2432, individually resulted in no defects in growth, cell morphology, drug susceptibility or spatial incorporation of new peptidoglycan. In contrast, deletion of MSMEG_6113 (dacB) was only possible in a merodiploid strain expressing the homologous M. tuberculosis operon encoding Rv3627c (dacB), Rv3626c, Rv3625c (mesJ) and Rv3624c (hpt), suggestive of essentiality. To investigate the role of this operon in mycobacterial growth, we depleted gene expression using anhydrotetracycline-responsive repressors and noted reduced bipolar peptidoglycan synthesis. These data point to a possible role for this four gene operon, which is highly conserved across all mycobacterial species, in regulating spatial localization of peptidoglycan synthesis.
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Affiliation(s)
- Christopher S Ealand
- DST/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, P.O. Box 1038, Johannesburg, 2000, South Africa
| | - Rukaya Asmal
- DST/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, P.O. Box 1038, Johannesburg, 2000, South Africa
| | - Lethabo Mashigo
- DST/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, P.O. Box 1038, Johannesburg, 2000, South Africa
| | - Lisa Campbell
- DST/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, P.O. Box 1038, Johannesburg, 2000, South Africa
| | - Bavesh D Kana
- DST/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, P.O. Box 1038, Johannesburg, 2000, South Africa.
- MRC-CAPRISA HIV-TB Pathogenesis and Treatment Research Unit, Centre for the AIDS Programme of Research in South Africa, CAPRISA, Durban, South Africa.
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41
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Hohl M, Remm S, Eskandarian HA, Dal Molin M, Arnold FM, Hürlimann LM, Krügel A, Fantner GE, Sander P, Seeger MA. Increased drug permeability of a stiffened mycobacterial outer membrane in cells lacking MFS transporter Rv1410 and lipoprotein LprG. Mol Microbiol 2019; 111:1263-1282. [PMID: 30742339 PMCID: PMC6519032 DOI: 10.1111/mmi.14220] [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] [Accepted: 02/06/2019] [Indexed: 12/18/2022]
Abstract
The major facilitator superfamily transporter Rv1410 and the lipoprotein LprG (Rv1411) are encoded by a conserved two-gene operon and contribute to virulence in Mycobacterium tuberculosis. Rv1410 was originally postulated to function as a drug efflux pump, but recent studies suggested that Rv1410 and LprG work in concert to insert triacylglycerides and lipoarabinomannans into the outer membrane. Here, we conducted microscopic analyses of Mycobacterium smegmatis lacking the operon and observed a cell separation defect, while surface rigidity measured by atomic force microscopy was found to be increased. Whereas Rv1410 expressed in Lactococcus lactis did not confer drug resistance, deletion of the operon in Mycobacterium abscessus and M. smegmatis resulted in increased susceptibility toward vancomycin, novobiocin and rifampicin. A homology model of Rv1410 revealed a periplasmic loop as well as a highly conserved aspartate, which were found to be essential for the operon's function. Interestingly, influx of the fluorescent dyes BCECF-AM and calcein-AM in de-energized M. smegmatis cells was faster in the deletion mutant. Our results unambiguously show that elevated drug susceptibility in the deletion mutant is caused by increased drug influx through a defective mycobacterial cell envelope and not by drug efflux mediated by Rv1410.
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Affiliation(s)
- Michael Hohl
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Sille Remm
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Haig A Eskandarian
- Global Health Institute, École polytechnique fédérale de Lausanne, EPFL, Lausanne, Switzerland
| | - Michael Dal Molin
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Fabian M Arnold
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Lea M Hürlimann
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Andri Krügel
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Georg E Fantner
- Interfaculty Institute for Bioengineering, École polytechnique fédérale de Lausanne, EPFL, Lausanne, Switzerland
| | - Peter Sander
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland.,National Center for Mycobacteria, Zurich, Switzerland
| | - Markus A Seeger
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
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42
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Abstract
Spatial organization is a hallmark of all living systems. Even bacteria, the smallest forms of cellular life, display defined shapes and complex internal organization, showcasing a highly structured genome, cytoskeletal filaments, localized scaffolding structures, dynamic spatial patterns, active transport, and occasionally, intracellular organelles. Spatial order is required for faithful and efficient cellular replication and offers a powerful means for the development of unique biological properties. Here, we discuss organizational features of bacterial cells and highlight how bacteria have evolved diverse spatial mechanisms to overcome challenges cells face as self-replicating entities.
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43
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Murphy KC, Nelson SJ, Nambi S, Papavinasasundaram K, Baer CE, Sassetti CM. ORBIT: a New Paradigm for Genetic Engineering of Mycobacterial Chromosomes. mBio 2018; 9:e01467-18. [PMID: 30538179 PMCID: PMC6299477 DOI: 10.1128/mbio.01467-18] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/19/2018] [Indexed: 11/20/2022] Open
Abstract
Two efficient recombination systems were combined to produce a versatile method for chromosomal engineering that obviates the need to prepare double-stranded DNA (dsDNA) recombination substrates. A synthetic "targeting oligonucleotide" is incorporated into the chromosome via homologous recombination mediated by the phage Che9c RecT annealase. This oligonucleotide contains a site-specific recombination site for the directional Bxb1 integrase (Int), which allows the simultaneous integration of a "payload plasmid" that contains a cognate recombination site and a selectable marker. The targeting oligonucleotide and payload plasmid are cotransformed into a RecT- and Int-expressing strain, and drug-resistant homologous recombinants are selected in a single step. A library of reusable target-independent payload plasmids is available to generate gene knockouts, promoter replacements, or C-terminal tags. This new system is called ORBIT (for "oligonucleotide-mediated recombineering followed by Bxb1 integrase targeting") and is ideally suited for the creation of libraries consisting of large numbers of deletions, insertions, or fusions in a bacterial chromosome. We demonstrate the utility of this "drag and drop" strategy by the construction of insertions or deletions in over 100 genes in Mycobacteriumtuberculosis and M. smegmatisIMPORTANCE We sought to develop a system that could increase the usefulness of oligonucleotide-mediated recombineering of bacterial chromosomes by expanding the types of modifications generated by an oligonucleotide (i.e., insertions and deletions) and by making recombinant formation a selectable event. This paper describes such a system for use in M. smegmatis and M. tuberculosis By incorporating a single-stranded DNA (ssDNA) version of the phage Bxb1 attP site into the oligonucleotide and coelectroporating it with a nonreplicative plasmid that carries an attB site and a drug selection marker, we show both formation of a chromosomal attP site and integration of the plasmid in a single transformation. No target-specific dsDNA substrates are required. This system will allow investigators studying mycobacterial diseases, including tuberculosis, to easily generate multiple mutants for analysis of virulence factors, identification of new drug targets, and development of new vaccines.
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Affiliation(s)
- Kenan C Murphy
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Samantha J Nelson
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Subhalaxmi Nambi
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Kadamba Papavinasasundaram
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Christina E Baer
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Christopher M Sassetti
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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44
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Melzer ES, Sein CE, Chambers JJ, Siegrist MS. DivIVA concentrates mycobacterial cell envelope assembly for initiation and stabilization of polar growth. Cytoskeleton (Hoboken) 2018; 75:498-507. [PMID: 30160378 PMCID: PMC6644302 DOI: 10.1002/cm.21490] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 06/07/2018] [Accepted: 06/27/2018] [Indexed: 12/31/2022]
Abstract
In many model organisms, diffuse patterning of cell wall peptidoglycan synthesis by the actin homolog MreB enables the bacteria to maintain their characteristic rod shape. In Caulobacter crescentus and Escherichia coli, MreB is also required to sculpt this morphology de novo. Mycobacteria are rod-shaped but expand their cell wall from discrete polar or subpolar zones. In this genus, the tropomyosin-like protein DivIVA is required for the maintenance of cell morphology. DivIVA has also been proposed to direct peptidoglycan synthesis to the tips of the mycobacterial cell. The precise nature of this regulation is unclear, as is its role in creating rod shape from scratch. We find that DivIVA localizes nascent cell wall and covalently associated mycomembrane but is dispensable for the assembly process itself. Mycobacterium smegmatis rendered spherical by peptidoglycan digestion or by DivIVA depletion are able to regain rod shape at the population level in the presence of DivIVA. At the single cell level, there is a close spatiotemporal correlation between DivIVA foci, rod extrusion and concentrated cell wall synthesis. Thus, although the precise mechanistic details differ from other organisms, M. smegmatis also establish and propagate rod shape by cytoskeleton-controlled patterning of peptidoglycan. Our data further support the emerging notion that morphology is a hardwired trait of bacterial cells.
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Affiliation(s)
- Emily S Melzer
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts
| | - Caralyn E Sein
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts
| | - James J Chambers
- Institute for Applied Life Sciences, University of Massachusetts, Amherst, Massachusetts
| | - M Sloan Siegrist
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts.,Molecular and Cellular Biology, University of Massachusetts, Amherst, Massachusetts
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45
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Trojanowski D, Hołówka J, Zakrzewska-Czerwińska J. Where and When Bacterial Chromosome Replication Starts: A Single Cell Perspective. Front Microbiol 2018; 9:2819. [PMID: 30534115 PMCID: PMC6275241 DOI: 10.3389/fmicb.2018.02819] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Accepted: 11/02/2018] [Indexed: 12/18/2022] Open
Abstract
Bacterial chromosomes have a single, unique replication origin (named oriC), from which DNA synthesis starts. This study describes methods of visualizing oriC regions and the chromosome replication in single living bacterial cells in real-time. This review also discusses the impact of live cell imaging techniques on understanding of chromosome replication dynamics, particularly at the initiation step, in different species of bacteria.
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Affiliation(s)
- Damian Trojanowski
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
| | - Joanna Hołówka
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
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46
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Gorla P, Plocinska R, Sarva K, Satsangi AT, Pandeeti E, Donnelly R, Dziadek J, Rajagopalan M, Madiraju MV. MtrA Response Regulator Controls Cell Division and Cell Wall Metabolism and Affects Susceptibility of Mycobacteria to the First Line Antituberculosis Drugs. Front Microbiol 2018; 9:2839. [PMID: 30532747 PMCID: PMC6265350 DOI: 10.3389/fmicb.2018.02839] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 11/05/2018] [Indexed: 11/25/2022] Open
Abstract
The biological processes regulated by the essential response regulator MtrA and the growth conditions promoting its activation in Mycobacterium tuberculosis, a slow grower and pathogen, are largely unknown. Here, using a gain-of-function mutant, MtrAY 102C, which functions in the absence of the cognate MtrB sensor kinase, we show that the MtrA regulon includes several genes involved in the processes of cell division and cell wall metabolism. The expression of selected MtrA targets and intracellular MtrA levels were compromised under replication arrest induced by genetic manipulation and under stress conditions caused by toxic radicals. The loss of the mtrA gene in M. smegmatis, a rapid grower and non-pathogen, produced filamentous cells with branches and bulges, indicating defects in cell division and cell shape. The ΔmtrA mutant was sensitized to rifampicin and vancomycin and became more resistant to isoniazid, the first line antituberculosis drug. Our data are consistent with the proposal that MtrA controls the optimal cell division, cell wall integrity, and susceptibility to some antimycobacterial drugs.
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Affiliation(s)
- Purushotham Gorla
- Biomedical Research, The University of Texas Health Science Center, Tyler, TX, United States
| | - Renata Plocinska
- Institute of Medical Biology, Polish Academy of Sciences, Lodz, Poland
| | - Krishna Sarva
- Biomedical Research, The University of Texas Health Science Center, Tyler, TX, United States
| | - Akash T Satsangi
- Biomedical Research, The University of Texas Health Science Center, Tyler, TX, United States
| | - Emmanuel Pandeeti
- Biomedical Research, The University of Texas Health Science Center, Tyler, TX, United States
| | - Robert Donnelly
- Department of Pathology and Laboratory Medicine, Rutgers New Jersey Medical School, Newark, NJ, United States
| | - Jaroslaw Dziadek
- Institute of Medical Biology, Polish Academy of Sciences, Lodz, Poland
| | - Malini Rajagopalan
- Biomedical Research, The University of Texas Health Science Center, Tyler, TX, United States
| | - Murty V Madiraju
- Biomedical Research, The University of Texas Health Science Center, Tyler, TX, United States
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47
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Sommer R, Neres J, Piton J, Dhar N, van der Sar A, Mukherjee R, Laroche T, Dyson PJ, McKinney JD, Bitter W, Makarov V, Cole ST. Fluorescent Benzothiazinone Analogues Efficiently and Selectively Label Dpre1 in Mycobacteria and Actinobacteria. ACS Chem Biol 2018; 13:3184-3192. [PMID: 30289689 DOI: 10.1021/acschembio.8b00790] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Benzothiazinones (BTZ) are highly potent bactericidal inhibitors of mycobacteria and the lead compound, BTZ043, and the optimized drug candidate, PBTZ169, have potential for the treatment of tuberculosis. Here, we exploited the tractability of the BTZ scaffold by attaching a range of fluorophores to the 2-substituent of the BTZ ring via short linkers. We show by means of fluorescence imaging that the most advanced derivative, JN108, is capable of efficiently labeling its target, the essential flavoenzyme DprE1, both in cell-free extracts and after purification as well as in growing cells of different actinobacterial species. DprE1 displays a polar localization in Mycobacterium tuberculosis, M. marinum, M. smegmatis, and Nocardia farcinica but not in Corynebacterium glutamicum. Finally, mutation of the cysteine residue in DprE1 in these species, to which BTZ covalently binds, abolishes completely the interaction with JN108, thereby highlighting the specificity of this fluorescent probe.
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Affiliation(s)
- Raphael Sommer
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | - João Neres
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
- More Medicines for Tuberculosis (MM4TB) Consortium (www.mm4tb.org), EPFL, 1015 Lausanne, Switzerland
| | - Jérémie Piton
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
- More Medicines for Tuberculosis (MM4TB) Consortium (www.mm4tb.org), EPFL, 1015 Lausanne, Switzerland
| | - Neeraj Dhar
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
- More Medicines for Tuberculosis (MM4TB) Consortium (www.mm4tb.org), EPFL, 1015 Lausanne, Switzerland
| | - Astrid van der Sar
- Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Raju Mukherjee
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
- More Medicines for Tuberculosis (MM4TB) Consortium (www.mm4tb.org), EPFL, 1015 Lausanne, Switzerland
| | - Thierry Laroche
- Faculty of Life Sciences (SV), BioImaging and Optics Platform (BIOP), Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 15, 1015, Lausanne, Switzerland
| | - Paul J. Dyson
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, 1015, Switzerland
| | - John D. McKinney
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
- More Medicines for Tuberculosis (MM4TB) Consortium (www.mm4tb.org), EPFL, 1015 Lausanne, Switzerland
| | - Wilbert Bitter
- Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Vadim Makarov
- Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia
| | - Stewart T. Cole
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
- More Medicines for Tuberculosis (MM4TB) Consortium (www.mm4tb.org), EPFL, 1015 Lausanne, Switzerland
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48
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Pióro M, Małecki T, Portas M, Magierowska I, Trojanowski D, Sherratt D, Zakrzewska-Czerwińska J, Ginda K, Jakimowicz D. Competition between DivIVA and the nucleoid for ParA binding promotes segrosome separation and modulates mycobacterial cell elongation. Mol Microbiol 2018; 111:204-220. [PMID: 30318635 PMCID: PMC7379644 DOI: 10.1111/mmi.14149] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/09/2018] [Indexed: 01/03/2023]
Abstract
Although mycobacteria are rod shaped and divide by simple binary fission, their cell cycle exhibits unusual features: unequal cell division producing daughter cells that elongate with different velocities, as well as asymmetric chromosome segregation and positioning throughout the cell cycle. As in other bacteria, mycobacterial chromosomes are segregated by pair of proteins, ParA and ParB. ParA is an ATPase that interacts with nucleoprotein ParB complexes – segrosomes and non‐specifically binds the nucleoid. Uniquely in mycobacteria, ParA interacts with a polar protein DivIVA (Wag31), responsible for asymmetric cell elongation, however the biological role of this interaction remained unknown. We hypothesised that this interaction plays a critical role in coordinating chromosome segregation with cell elongation. Using a set of ParA mutants, we determined that disruption of ParA‐DNA binding enhanced the interaction between ParA and DivIVA, indicating a competition between the nucleoid and DivIVA for ParA binding. Having identified the ParA mutation that disrupts its recruitment to DivIVA, we found that it led to inefficient segrosomes separation and increased the cell elongation rate. Our results suggest that ParA modulates DivIVA activity. Thus, we demonstrate that the ParA‐DivIVA interaction facilitates chromosome segregation and modulates cell elongation.
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Affiliation(s)
- Monika Pióro
- Laboratory of Molecular Biology of Microorganisms, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Tomasz Małecki
- Faculty of Biotechnology, Department of Molecular Microbiology, University of Wrocław, Wrocław, Poland
| | - Magda Portas
- Faculty of Biotechnology, Department of Molecular Microbiology, University of Wrocław, Wrocław, Poland
| | - Izabela Magierowska
- Faculty of Biotechnology, Department of Molecular Microbiology, University of Wrocław, Wrocław, Poland
| | - Damian Trojanowski
- Faculty of Biotechnology, Department of Molecular Microbiology, University of Wrocław, Wrocław, Poland
| | - David Sherratt
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Jolanta Zakrzewska-Czerwińska
- Laboratory of Molecular Biology of Microorganisms, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.,Faculty of Biotechnology, Department of Molecular Microbiology, University of Wrocław, Wrocław, Poland
| | - Katarzyna Ginda
- Faculty of Biotechnology, Department of Molecular Microbiology, University of Wrocław, Wrocław, Poland.,Department of Biochemistry, University of Oxford, Oxford, UK
| | - Dagmara Jakimowicz
- Laboratory of Molecular Biology of Microorganisms, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.,Faculty of Biotechnology, Department of Molecular Microbiology, University of Wrocław, Wrocław, Poland
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49
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Baranowski C, Welsh MA, Sham LT, Eskandarian HA, Lim HC, Kieser KJ, Wagner JC, McKinney JD, Fantner GE, Ioerger TR, Walker S, Bernhardt TG, Rubin EJ, Rego EH. Maturing Mycobacterium smegmatis peptidoglycan requires non-canonical crosslinks to maintain shape. eLife 2018; 7:37516. [PMID: 30324906 PMCID: PMC6231781 DOI: 10.7554/elife.37516] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 10/11/2018] [Indexed: 01/06/2023] Open
Abstract
In most well-studied rod-shaped bacteria, peptidoglycan is primarily crosslinked by penicillin-binding proteins (PBPs). However, in mycobacteria, crosslinks formed by L,D-transpeptidases (LDTs) are highly abundant. To elucidate the role of these unusual crosslinks, we characterized Mycobacterium smegmatis cells lacking all LDTs. We find that crosslinks generate by LDTs are required for rod shape maintenance specifically at sites of aging cell wall, a byproduct of polar elongation. Asymmetric polar growth leads to a non-uniform distribution of these two types of crosslinks in a single cell. Consequently, in the absence of LDT-mediated crosslinks, PBP-catalyzed crosslinks become more important. Because of this, Mycobacterium tuberculosis (Mtb) is more rapidly killed using a combination of drugs capable of PBP- and LDT- inhibition. Thus, knowledge about the spatial and genetic relationship between drug targets can be exploited to more effectively treat this pathogen. Most bacteria have a cell wall that protects them and maintains their shape. Many of these organisms make their cell walls from fibers of proteins and sugars, called peptidoglycan. As bacteria grow, peptidoglycan is constantly broken down and reassembled, and in many species, new units of peptidoglycan are added into the sidewall. However, in a group of bacteria called mycobacteria, which cause tuberculosis and other diseases, the units are added at the tips. The peptidoglycan layer is often a successful target for antibiotic treatments. But, drugs that treat tuberculosis do not attack this layer, partly because we know very little about the cell walls of mycobacteria. Here, Baranowski et al. used genetic manipulation and microscopy to study how mycobacteria build their cell wall. The results showed that these bacteria link peptidoglycan units together in an unusual way. In most bacteria, peptidoglycan units are connected by chemical links known as 4-3 crosslinks. This is initially the same in mycobacteria, but as the cell grows and the cell wall expands, these bonds break and so-called 3-3 crosslinks form. In genetically modified bacteria that could not form these 3-3 bonds, the cell wall became brittle and weak, and the bacteria eventually died. These findings could be important for developing new drugs that treat infections caused by mycobacteria. Baranowski et al. demonstrate that a combination of drugs blocking both 4-3 and 3-3 crosslinks is particularly effective at killing the bacterium that causes tuberculosis.
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Affiliation(s)
- Catherine Baranowski
- Department of Immunology and Infectious Disease, Harvard TH Chan School of Public Health, Boston, United States
| | - Michael A Welsh
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
| | - Lok-To Sham
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States.,Department of Microbiology and Immunology, National University of Singapore, Singapore, Singapore
| | - Haig A Eskandarian
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland.,School of Engineering, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland
| | - Hoong Chuin Lim
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
| | - Karen J Kieser
- Department of Immunology and Infectious Disease, Harvard TH Chan School of Public Health, Boston, United States
| | - Jeffrey C Wagner
- Department of Immunology and Infectious Disease, Harvard TH Chan School of Public Health, Boston, United States
| | - John D McKinney
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland
| | - Georg E Fantner
- School of Engineering, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland
| | - Thomas R Ioerger
- Department of Computer Science and Engineering, Texas A&M University, Texas, United States
| | - Suzanne Walker
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
| | - Thomas G Bernhardt
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
| | - Eric J Rubin
- Department of Immunology and Infectious Disease, Harvard TH Chan School of Public Health, Boston, United States.,Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
| | - E Hesper Rego
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, United States
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Raghavendra T, Patil S, Mukherjee R. Peptidoglycan in Mycobacteria: chemistry, biology and intervention. Glycoconj J 2018; 35:421-432. [DOI: 10.1007/s10719-018-9842-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/20/2018] [Accepted: 09/05/2018] [Indexed: 01/07/2023]
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