1
|
Boutillon A, Banavar SP, Campàs O. Conserved physical mechanisms of cell and tissue elongation. Development 2024; 151:dev202687. [PMID: 38767601 PMCID: PMC11190436 DOI: 10.1242/dev.202687] [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] [Indexed: 05/22/2024]
Abstract
Living organisms have the ability to self-shape into complex structures appropriate for their function. The genetic and molecular mechanisms that enable cells to do this have been extensively studied in several model and non-model organisms. In contrast, the physical mechanisms that shape cells and tissues have only recently started to emerge, in part thanks to new quantitative in vivo measurements of the physical quantities guiding morphogenesis. These data, combined with indirect inferences of physical characteristics, are starting to reveal similarities in the physical mechanisms underlying morphogenesis across different organisms. Here, we review how physics contributes to shape cells and tissues in a simple, yet ubiquitous, morphogenetic transformation: elongation. Drawing from observed similarities across species, we propose the existence of conserved physical mechanisms of morphogenesis.
Collapse
Affiliation(s)
- Arthur Boutillon
- Cluster of Excellence Physics of Life, TU Dresden, 01062 Dresden, Germany
| | - Samhita P. Banavar
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08540, USA
| | - Otger Campàs
- Cluster of Excellence Physics of Life, TU Dresden, 01062 Dresden, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
- Center for Systems Biology Dresden, 01307 Dresden, Germany
| |
Collapse
|
2
|
Nieto C, Täuber S, Blöbaum L, Vahdat Z, Grünberger A, Singh A. Coupling Cell Size Regulation and Proliferation Dynamics of C. glutamicum Reveals Cell Division Based on Surface Area. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.26.573217. [PMID: 38234762 PMCID: PMC10793411 DOI: 10.1101/2023.12.26.573217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Single cells actively coordinate growth and division to regulate their size, yet how this size homeostasis at the single-cell level propagates over multiple generations to impact clonal expansion remains fundamentally unexplored. Classical timer models for cell proliferation (where the duration of the cell cycle is an independent variable) predict that the stochastic variation in colony size will increase monotonically over time. In stark contrast, implementing size control according to adder strategy (where on average a fixed size added from cell birth to division) leads to colony size variations that eventually decay to zero. While these results assume a fixed size of the colony-initiating progenitor cell, further analysis reveals that the magnitude of the intercolony variation in population number is sensitive to heterogeneity in the initial cell size. We validate these predictions by tracking the growth of isogenic microcolonies of Corynebacterium glutamicum in microfluidic chambers. Approximating their cell shape to a capsule, we observe that the degree of random variability in cell size is different depending on whether the cell size is quantified as per length, surface area, or volume, but size control remains an adder regardless of these size metrics. A comparison of the observed variability in the colony population with the predictions suggests that proliferation matches better with a cell division based on the cell surface. In summary, our integrated mathematical-experimental approach bridges the paradigms of single-cell size regulation and clonal expansion at the population levels. This innovative approach provides elucidation of the mechanisms of size homeostasis from the stochastic dynamics of colony size for rod-shaped microbes.
Collapse
Affiliation(s)
- César Nieto
- Department of Electrical and Computing Engineering, University of Delaware. Newark, DE 19716, USA
| | - Sarah Täuber
- CeBiTec, Bielefeld University. Bielefeld, Germany
- Multiscale Bioengineering, Technical Faculty, Bielefeld University. Bielefeld, Germany
| | - Luisa Blöbaum
- CeBiTec, Bielefeld University. Bielefeld, Germany
- Multiscale Bioengineering, Technical Faculty, Bielefeld University. Bielefeld, Germany
| | - Zahra Vahdat
- Department of Electrical and Computing Engineering, University of Delaware. Newark, DE 19716, USA
| | - Alexander Grünberger
- CeBiTec, Bielefeld University. Bielefeld, Germany
- Multiscale Bioengineering, Technical Faculty, Bielefeld University. Bielefeld, Germany
- Institute of Process Engineering in Life Sciences: Microsystems in Bioprocess Engineering, Karlsruhe Institute of Technology. Karlsruhe, Germany
| | - Abhyudai Singh
- Department of Electrical and Computing Engineering, University of Delaware. Newark, DE 19716, USA
- Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE 19716 USA
| |
Collapse
|
3
|
Avila‐Cobian LF, Hoshino H, Horsman ME, Nguyen VT, Qian Y, Feltzer R, Kim C, Hu DD, Champion MM, Fisher JF, Mobashery S. Amber-codon suppression for spatial localization and in vivo photoaffinity capture of the interactome of the Pseudomonas aeruginosa rare lipoprotein A lytic transglycosylase. Protein Sci 2023; 32:e4781. [PMID: 37703013 PMCID: PMC10536563 DOI: 10.1002/pro.4781] [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: 07/27/2023] [Revised: 09/06/2023] [Accepted: 09/11/2023] [Indexed: 09/14/2023]
Abstract
The 11 lytic transglycosylases of Pseudomonas aeruginosa have overlapping activities in the turnover of the cell-wall peptidoglycan. Rare lipoprotein A (RlpA) is distinct among the 11 by its use of only peptidoglycan lacking peptide stems. The spatial localization of RlpA and its interactome within P. aeruginosa are unknown. We employed suppression of introduced amber codons at sites in the rlpA gene for the introduction of the unnatural-amino-acids Νζ -[(2-azidoethoxy)carbonyl]-l-lysine (compound 1) and Nζ -[[[3-(3-methyl-3H-diazirin-3-yl)propyl]amino]carbonyl]-l-lysine (compound 2). In live P. aeruginosa, full-length RlpA incorporating compound 1 into its sequence was fluorescently tagged using strained-promoted alkyne-azide cycloaddition and examined by fluorescence microscopy. RlpA is present at low levels along the sidewall length of the bacterium, and at higher levels at the nascent septa of replicating bacteria. In intact P. aeruginosa, UV photolysis of full-length RlpA having compound 2 within its sequence generated a transient reactive carbene, which engaged in photoaffinity capture of neighboring proteins. Thirteen proteins were identified. Three of these proteins-PBP1a, PBP5, and MreB-are members of the bacterial divisome. The use of the complementary methodologies of non-canonical amino-acid incorporation, photoaffinity proximity analysis, and fluorescent microscopy confirm a dominant septal location for the RlpA enzyme of P. aeruginosa, as a divisome-associated activity. This accomplishment adds to the emerging recognition of the value of these methodologies for identification of the intracellular localization of bacterial proteins.
Collapse
Affiliation(s)
- Luis F. Avila‐Cobian
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Hidekazu Hoshino
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Mark E. Horsman
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Van T. Nguyen
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Yuanyuan Qian
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Rhona Feltzer
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Choon Kim
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Daniel D. Hu
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Matthew M. Champion
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Jed F. Fisher
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Shahriar Mobashery
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| |
Collapse
|
4
|
Gómez-Arrebola C, Hernandez SB, Culp EJ, Wright GD, Solano C, Cava F, Lasa I. Staphylococcus aureus susceptibility to complestatin and corbomycin depends on the VraSR two-component system. Microbiol Spectr 2023; 11:e0037023. [PMID: 37646518 PMCID: PMC10581084 DOI: 10.1128/spectrum.00370-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 06/30/2023] [Indexed: 09/01/2023] Open
Abstract
The overuse of antibiotics in humans and livestock has driven the emergence and spread of antimicrobial resistance and has therefore prompted research on the discovery of novel antibiotics. Complestatin (Cm) and corbomycin (Cb) are glycopeptide antibiotics with an unprecedented mechanism of action that is active even against methicillin-resistant and daptomycin-resistant Staphylococcus aureus. They bind to peptidoglycan and block the activity of peptidoglycan hydrolases required for remodeling the cell wall during growth. Bacterial signaling through two-component transduction systems (TCSs) has been associated with the development of S. aureus antimicrobial resistance. However, the role of TCSs in S. aureus susceptibility to Cm and Cb has not been previously addressed. In this study, we determined that, among all 16 S. aureus TCSs, VraSR is the only one controlling the susceptibility to Cm and Cb. Deletion of vraSR increased bacterial susceptibility to both antibiotics. Epistasis analysis with members of the vraSR regulon revealed that deletion of spdC, which encodes a membrane protein that scaffolds SagB for cleavage of peptidoglycan strands to achieve physiological length, in the vraSR mutant restored Cm and Cb susceptibility to wild-type levels. Moreover, deletion of either spdC or sagB in the wild-type strain increased resistance to both antibiotics. Further analyses revealed a significant rise in the relative amount of peptidoglycan and its total degree of cross-linkage in ΔspdC and ΔsagB mutants compared to the wild-type strain, suggesting that these changes in the cell wall provide resistance to the damaging effect of Cm and Cb. IMPORTANCE Although Staphylococcus aureus is a common colonizer of the skin and digestive tract of humans and many animals, it is also a versatile pathogen responsible for causing a wide variety and number of infections. Treatment of these infections requires the bacteria to be constantly exposed to antibiotic treatment, which facilitates the selection of antibiotic-resistant strains. The development of new antibiotics is, therefore, urgently needed. In this paper, we investigated the role of the sensory system of S. aureus in susceptibility to two new antibiotics: corbomycin and complestatin. The results shed light on the cell-wall synthesis processes that are affected by the presence of the antibiotic and the sensory system responsible for coordinating their activity.
Collapse
Affiliation(s)
- Carmen Gómez-Arrebola
- Laboratory of Microbial Pathogenesis, Navarrabiomed, Hospital Universitario de Navarra (HUN), Universidad Pública de Navarra (UPNA), IdiSNA, Pamplona, Spain
| | - Sara B. Hernandez
- Department of Molecular Biology, Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Elizabeth J. Culp
- Department of Biochemistry and Biomedical Sciences, M. G. DeGroote Institute for Infectious Disease Research, David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, Ontario, Canada
| | - Gerard D. Wright
- Department of Biochemistry and Biomedical Sciences, M. G. DeGroote Institute for Infectious Disease Research, David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, Ontario, Canada
| | - Cristina Solano
- Laboratory of Microbial Pathogenesis, Navarrabiomed, Hospital Universitario de Navarra (HUN), Universidad Pública de Navarra (UPNA), IdiSNA, Pamplona, Spain
| | - Felipe Cava
- Department of Molecular Biology, Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Iñigo Lasa
- Laboratory of Microbial Pathogenesis, Navarrabiomed, Hospital Universitario de Navarra (HUN), Universidad Pública de Navarra (UPNA), IdiSNA, Pamplona, Spain
| |
Collapse
|
5
|
Nygaard R, Graham CLB, Belcher Dufrisne M, Colburn JD, Pepe J, Hydorn MA, Corradi S, Brown CM, Ashraf KU, Vickery ON, Briggs NS, Deering JJ, Kloss B, Botta B, Clarke OB, Columbus L, Dworkin J, Stansfeld PJ, Roper DI, Mancia F. Structural basis of peptidoglycan synthesis by E. coli RodA-PBP2 complex. Nat Commun 2023; 14:5151. [PMID: 37620344 PMCID: PMC10449877 DOI: 10.1038/s41467-023-40483-8] [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: 11/11/2022] [Accepted: 07/31/2023] [Indexed: 08/26/2023] Open
Abstract
Peptidoglycan (PG) is an essential structural component of the bacterial cell wall that is synthetized during cell division and elongation. PG forms an extracellular polymer crucial for cellular viability, the synthesis of which is the target of many antibiotics. PG assembly requires a glycosyltransferase (GT) to generate a glycan polymer using a Lipid II substrate, which is then crosslinked to the existing PG via a transpeptidase (TP) reaction. A Shape, Elongation, Division and Sporulation (SEDS) GT enzyme and a Class B Penicillin Binding Protein (PBP) form the core of the multi-protein complex required for PG assembly. Here we used single particle cryo-electron microscopy to determine the structure of a cell elongation-specific E. coli RodA-PBP2 complex. We combine this information with biochemical, genetic, spectroscopic, and computational analyses to identify the Lipid II binding sites and propose a mechanism for Lipid II polymerization. Our data suggest a hypothesis for the movement of the glycan strand from the Lipid II polymerization site of RodA towards the TP site of PBP2, functionally linking these two central enzymatic activities required for cell wall peptidoglycan biosynthesis.
Collapse
Affiliation(s)
- Rie Nygaard
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Chris L B Graham
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Meagan Belcher Dufrisne
- Department of Chemistry and Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, 22904, USA
| | - Jonathan D Colburn
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
| | - Joseph Pepe
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Molly A Hydorn
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Silvia Corradi
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, NY, 10032, USA
- Faculty of Pharmacy and Medicine, Sapienza University of Rome, Rome, Italy
| | - Chelsea M Brown
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
| | - Khuram U Ashraf
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Owen N Vickery
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
| | - Nicholas S Briggs
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - John J Deering
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Brian Kloss
- New York Consortium on Membrane Protein Structure, New York Structural Biology Center, 89 Convent Avenue, New York, NY, 10027, USA
| | - Bruno Botta
- Faculty of Pharmacy and Medicine, Sapienza University of Rome, Rome, Italy
| | - Oliver B Clarke
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, NY, 10032, USA
- Department of Anesthesiology, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Linda Columbus
- Department of Chemistry and Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, 22904, USA.
| | - Jonathan Dworkin
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, 10032, USA.
| | - Phillip J Stansfeld
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK.
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK.
| | - David I Roper
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK.
| | - Filippo Mancia
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, NY, 10032, USA.
| |
Collapse
|
6
|
Lee J, Cox JV, Ouellette SP. The Unique N-Terminal Domain of Chlamydial Bactofilin Mediates Its Membrane Localization and Ring-Forming Properties. J Bacteriol 2023; 205:e0009223. [PMID: 37191556 PMCID: PMC10294636 DOI: 10.1128/jb.00092-23] [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: 03/10/2023] [Accepted: 05/01/2023] [Indexed: 05/17/2023] Open
Abstract
Chlamydia trachomatis is an obligate intracellular bacterial pathogen. In evolving to the intracellular niche, Chlamydia has reduced its genome size compared to other bacteria and, as a consequence, has a number of unique features. For example, Chlamydia engages the actin-like protein MreB, rather than the tubulin-like protein FtsZ, to direct peptidoglycan (PG) synthesis exclusively at the septum of cells undergoing polarized cell division. Interestingly, Chlamydia possesses another cytoskeletal element-a bactofilin ortholog, BacA. Recently, we reported BacA is a cell size-determining protein that forms dynamic membrane-associated ring structures in Chlamydia that have not been observed in other bacteria with bactofilins. Chlamydial BacA possesses a unique N-terminal domain, and we hypothesized this domain imparts the membrane-binding and ring-forming properties of BacA. We show that different truncations of the N terminus result in distinct phenotypes: removal of the first 50 amino acids (ΔN50) results in large ring structures at the membrane whereas removal of the first 81 amino acids (ΔN81) results in an inability to form filaments and rings and a loss of membrane association. Overexpression of the ΔN50 isoform altered cell size, similar to loss of BacA, suggesting that the dynamic properties of BacA are essential for the regulation of cell size. We further show that the region from amino acid 51 to 81 imparts membrane association as appending it to green fluorescent protein (GFP) resulted in the relocalization of GFP from the cytosol to the membrane. Overall, our findings suggest two important functions for the unique N-terminal domain of BacA and help explain its role as a cell size determinant. IMPORTANCE Bacteria use a variety of filament-forming cytoskeletal proteins to regulate and control various aspects of their physiology. For example, the tubulin-like FtsZ recruits division proteins to the septum whereas the actin-like MreB recruits peptidoglycan (PG) synthases to generate the cell wall in rod-shaped bacteria. Recently, a third class of cytoskeletal protein has been identified in bacteria-bactofilins. These proteins have been primarily linked to spatially localized PG synthesis. Interestingly, Chlamydia, an obligate intracellular bacterium, does not have PG in its cell wall and yet possesses a bactofilin ortholog. In this study, we characterize a unique N-terminal domain of chlamydial bactofilin and show that this domain controls two important functions that affect cell size: its ring-forming and membrane-associating properties.
Collapse
Affiliation(s)
- Junghoon Lee
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - John V. Cox
- Department of Microbiology, Immunology, and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Scot P. Ouellette
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA
| |
Collapse
|
7
|
Trotta KL, Hayes BM, Schneider JP, Wang J, Todor H, Rockefeller Grimes P, Zhao Z, Hatleberg WL, Silvis MR, Kim R, Koo BM, Basler M, Chou S. Lipopolysaccharide transport regulates bacterial sensitivity to a cell wall-degrading intermicrobial toxin. PLoS Pathog 2023; 19:e1011454. [PMID: 37363922 PMCID: PMC10328246 DOI: 10.1371/journal.ppat.1011454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 07/07/2023] [Accepted: 06/01/2023] [Indexed: 06/28/2023] Open
Abstract
Gram-negative bacteria can antagonize neighboring microbes using a type VI secretion system (T6SS) to deliver toxins that target different essential cellular features. Despite the conserved nature of these targets, T6SS potency can vary across recipient species. To understand the functional basis of intrinsic T6SS susceptibility, we screened for essential Escherichia coli (Eco) genes that affect its survival when antagonized by a cell wall-degrading T6SS toxin from Pseudomonas aeruginosa, Tae1. We revealed genes associated with both the cell wall and a separate layer of the cell envelope, lipopolysaccharide, that modulate Tae1 toxicity in vivo. Disruption of genes in early lipopolysaccharide biosynthesis provided Eco with novel resistance to Tae1, despite significant cell wall degradation. These data suggest that Tae1 toxicity is determined not only by direct substrate damage, but also by indirect cell envelope homeostasis activities. We also found that Tae1-resistant Eco exhibited reduced cell wall synthesis and overall slowed growth, suggesting that reactive cell envelope maintenance pathways could promote, not prevent, self-lysis. Together, our study reveals the complex functional underpinnings of susceptibility to Tae1 and T6SS which regulate the impact of toxin-substrate interactions in vivo.
Collapse
Affiliation(s)
- Kristine L. Trotta
- Department of Biochemistry & Biophysics, University of California–San Francisco, San Francisco, California, United States of America
| | - Beth M. Hayes
- Department of Biochemistry & Biophysics, University of California–San Francisco, San Francisco, California, United States of America
| | | | - Jing Wang
- Biozentrum, University of Basel, Basel, Switzerland
| | - Horia Todor
- Department of Cell and Tissue Biology, University of California–San Francisco, San Francisco, California, United States of America
| | - Patrick Rockefeller Grimes
- Department of Biochemistry & Biophysics, University of California–San Francisco, San Francisco, California, United States of America
| | - Ziyi Zhao
- Department of Biochemistry & Biophysics, University of California–San Francisco, San Francisco, California, United States of America
| | | | - Melanie R. Silvis
- Department of Cell and Tissue Biology, University of California–San Francisco, San Francisco, California, United States of America
| | - Rachel Kim
- Department of Biochemistry & Biophysics, University of California–San Francisco, San Francisco, California, United States of America
| | - Byoung Mo Koo
- Department of Cell and Tissue Biology, University of California–San Francisco, San Francisco, California, United States of America
| | - Marek Basler
- Biozentrum, University of Basel, Basel, Switzerland
| | - Seemay Chou
- Department of Biochemistry & Biophysics, University of California–San Francisco, San Francisco, California, United States of America
| |
Collapse
|
8
|
Trotta KL, Hayes BM, Schneider JP, Wang J, Todor H, Grimes PR, Zhao Z, Hatleberg WL, Silvis MR, Kim R, Koo BM, Basler M, Chou S. Lipopolysaccharide integrity primes bacterial sensitivity to a cell wall-degrading intermicrobial toxin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.20.524922. [PMID: 36747731 PMCID: PMC9900751 DOI: 10.1101/2023.01.20.524922] [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: 01/22/2023]
Abstract
Gram-negative bacteria can antagonize neighboring microbes using a type VI secretion system (T6SS) to deliver toxins that target different essential cellular features. Despite the conserved nature of these targets, T6SS potency can vary across recipient species. To understand the molecular basis of intrinsic T6SS susceptibility, we screened for essential Escherichia coli genes that affect its survival when antagonized by a cell wall-degrading T6SS toxin from Pseudomonas aeruginosa , Tae1. We revealed genes associated with both the cell wall and a separate layer of the cell envelope, surface lipopolysaccharide, that modulate Tae1 toxicity in vivo . Disruption of lipopolysaccharide synthesis provided Escherichia coli (Eco) with novel resistance to Tae1, despite significant cell wall degradation. These data suggest that Tae1 toxicity is determined not only by direct substrate damage, but also by indirect cell envelope homeostasis activities. We also found that Tae1-resistant Eco exhibited reduced cell wall synthesis and overall slowed growth, suggesting that reactive cell envelope maintenance pathways could promote, not prevent, self-lysis. Together, our study highlights the consequences of co-regulating essential pathways on recipient fitness during interbacterial competition, and how antibacterial toxins leverage cellular vulnerabilities that are both direct and indirect to their specific targets in vivo .
Collapse
Affiliation(s)
- Kristine L Trotta
- Department of Biochemistry & Biophysics, University of California – San Francisco, San Francisco, CA, USA
| | - Beth M Hayes
- Department of Biochemistry & Biophysics, University of California – San Francisco, San Francisco, CA, USA
| | - Johannes P Schneider
- Focal Area Infection Biology, Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH - 4056 Basel, Switzerland
| | - Jing Wang
- Focal Area Infection Biology, Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH - 4056 Basel, Switzerland
| | - Horia Todor
- Department of Cell and Tissue Biology, University of California – San Francisco, San Francisco, CA, USA
| | - Patrick Rockefeller Grimes
- Department of Biochemistry & Biophysics, University of California – San Francisco, San Francisco, CA, USA
| | - Ziyi Zhao
- Department of Biochemistry & Biophysics, University of California – San Francisco, San Francisco, CA, USA
| | | | - Melanie R Silvis
- Department of Cell and Tissue Biology, University of California – San Francisco, San Francisco, CA, USA
| | - Rachel Kim
- Department of Biochemistry & Biophysics, University of California – San Francisco, San Francisco, CA, USA
| | - Byoung Mo Koo
- Department of Cell and Tissue Biology, University of California – San Francisco, San Francisco, CA, USA
| | - Marek Basler
- Focal Area Infection Biology, Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH - 4056 Basel, Switzerland
| | - Seemay Chou
- Department of Biochemistry & Biophysics, University of California – San Francisco, San Francisco, CA, USA
| |
Collapse
|
9
|
Hashmi HB, Farooq MA, Khan MH, Alshammari A, Aljasham AT, Rashid SA, Khan NR, Hashmi IB, Badar M, Mubarak MS. Collaterally Sensitive β-Lactam Drugs as an Effective Therapy against the Pre-Existing Methicillin Resistant Staphylococcus aureus (MRSA) Biofilms. Pharmaceuticals (Basel) 2023; 16:ph16050687. [PMID: 37242471 DOI: 10.3390/ph16050687] [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: 03/07/2023] [Revised: 04/01/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is among the leading causes of nosocomial infections and forms biofilms, which are difficult to eradicate because of their increasing resistance to antimicrobial agents. This is especially true for pre-existing biofilms. The current study focused on evaluating the efficacy of three β-lactam drugs, meropenem, piperacillin, and tazobactam, alone and in combination against the MRSA biofilms. When used individually, none of the drugs exhibited significant antibacterial activity against MRSA in a planktonic state. At the same time, the combination of meropenem, piperacillin, and tazobactam showed a 41.7 and 41.3% reduction in planktonic bacterial cell growth, respectively. These drugs were further assessed for biofilm inhibition and removal. The combination of meropenem, piperacillin, and tazobactam caused 44.3% biofilm inhibition, while the rest of the combinations did not show any significant effects. Results also revealed that piperacillin and tazobactam exhibited the best synergy against the pre-formed biofilm of MRSA, with 46% removal. However, adding meropenem to the piperacillin and tazobactam combination showed a slightly reduced activity towards the pre-formed biofilm of MRSA and removed 38.7% of it. Although the mechanism of synergism is not fully understood, our findings suggest that these three β-lactam drugs can be used in combination as very effective therapeutic agents for the treatment of pre-existing MRSA biofilms. The in vivo experiments on the antibiofilm activity of these drugs will pave the way for applying such synergistic combinations to clinics.
Collapse
Affiliation(s)
- Hamna Batool Hashmi
- Gomal Center of Biochemistry and Biotechnology, Gomal University, Dera Ismail Khan 29050, Pakistan
| | - Muhammad Asad Farooq
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, East China Normal University, Shanghai 200062, China
| | - Muhammad Hashim Khan
- Gomal Center of Biochemistry and Biotechnology, Gomal University, Dera Ismail Khan 29050, Pakistan
| | - Abdulrahman Alshammari
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Alanoud T Aljasham
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Sheikh Abdur Rashid
- Nanocarriers Research Laboratory, Gomal Centre of Pharmaceutical Sciences, Faculty of Pharmacy, Gomal University, Dera Ismail Khan 29050, Pakistan
| | - Nauman Rahim Khan
- Department of Pharmacy, Kohat University of Science and Technology, Kohat 26000, Pakistan
| | - Irum Batool Hashmi
- Department of Obstetrics and Gynecology, Gomal Medical College, Dera Ismail Khan 29050, Pakistan
| | - Muhammad Badar
- Gomal Center of Biochemistry and Biotechnology, Gomal University, Dera Ismail Khan 29050, Pakistan
| | - Mohammad S Mubarak
- Department of Chemistry, The University of Jordan, Amma 11942, Jordan
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| |
Collapse
|
10
|
Käshammer L, van den Ent F, Jeffery M, Jean NL, Hale VL, Löwe J. Cryo-EM structure of the bacterial divisome core complex and antibiotic target FtsWIQBL. Nat Microbiol 2023:10.1038/s41564-023-01368-0. [PMID: 37127704 DOI: 10.1038/s41564-023-01368-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 03/23/2023] [Indexed: 05/03/2023]
Abstract
In most bacteria, cell division relies on the synthesis of new cell wall material by the multiprotein divisome complex. Thus, at the core of the divisome are the transglycosylase FtsW, which synthesises peptidoglycan strands from its substrate Lipid II, and the transpeptidase FtsI that cross-links these strands to form a mesh, shaping and protecting the bacterial cell. The FtsQ-FtsB-FtsL trimeric complex interacts with the FtsWI complex and is involved in regulating its enzymatic activities; however, the structure of this pentameric complex is unknown. Here, we present the cryogenic electron microscopy structure of the FtsWIQBL complex from Pseudomonas aeruginosa at 3.7 Å resolution. Our work reveals intricate structural details, including an extended coiled coil formed by FtsL and FtsB and the periplasmic interaction site between FtsL and FtsI. Our structure explains the consequences of previously reported mutations and we postulate a possible activation mechanism involving a large conformational change in the periplasmic domain. As FtsWIQBL is central to the divisome, our structure is foundational for the design of future experiments elucidating the precise mechanism of bacterial cell division, an important antibiotic target.
Collapse
Affiliation(s)
- Lisa Käshammer
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Magnus Jeffery
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Nicolas L Jean
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Victoria L Hale
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Jan Löwe
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
| |
Collapse
|
11
|
Kunoh T, Yamamoto T, Ono E, Sugimoto S, Takabe K, Takeda M, Utada AS, Nomura N. Identification of lthB, a Gene Encoding a Putative Glycosyltransferase Family 8 Protein Required for Leptothrix Sheath Formation. Appl Environ Microbiol 2023; 89:e0191922. [PMID: 36951572 PMCID: PMC10132092 DOI: 10.1128/aem.01919-22] [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: 12/01/2022] [Accepted: 02/20/2023] [Indexed: 03/24/2023] Open
Abstract
The bacterium Leptothrix cholodnii generates cell chains encased in sheaths that are composed of woven nanofibrils. The nanofibrils are mainly composed of glycoconjugate repeats, and several glycosyltransferases (GTs) are required for its biosynthesis. However, only one GT (LthA) has been identified to date. In this study, we screened spontaneous variants of L. cholodnii SP6 to find those that form smooth colonies, which is one of the characteristics of sheathless variants. Genomic DNA sequencing of an isolated variant revealed an insertion in the locus Lcho_0972, which encodes a putative GT family 8 protein. We thus designated this protein LthB and characterized it using deletion mutants and antibodies. LthB localized adjacent to the cell envelope. ΔlthB cell chains were nanofibril free and thus sheathless, indicating that LthB is involved in nanofibril biosynthesis. Unlike the ΔlthA mutant and the wild-type strain, which often generate planktonic cells, most ΔlthB organisms presented as long cell chains under static conditions, resulting in deficient pellicle formation, which requires motile planktonic cells. These results imply that sheaths are not required for elongation of cell chains. Finally, calcium depletion, which induces cell chain breakage due to sheath loss, abrogated the expression of LthA, but not LthB, suggesting that these GTs cooperatively participate in glycoconjugate biosynthesis under different signaling controls. IMPORTANCE In recent years, the regulation of cell chain elongation of filamentous bacteria via extracellular signals has attracted attention as a potential strategy to prevent clogging of water distribution systems and filamentous bulking of activated sludge in industrial settings. However, a fundamental understanding of the ecology of filamentous bacteria remains elusive. Since sheath formation is associated with cell chain elongation in most of these bacteria, the molecular mechanisms underlying nanofibril sheath formation, including the intracellular signaling cascade in response to extracellular stimuli, must be elucidated. Here, we isolated a sheathless variant of L. cholodnii SP6 and thus identified a novel glycosyltransferase, LthB. Although mutants with deletions of lthA, encoding another GT, and lthB were both defective for nanofibril formation, they exhibited different phenotypes of cell chain elongation and pellicle formation. Moreover, LthA expression, but not LthB expression, was influenced by extracellular calcium, which is known to affect nanofibril formation, indicating the functional diversities of LthA and LthB. Such molecular insights are critical for a better understanding of ecology of filamentous bacteria, which, in turn, can be used to improve strategies to control filamentous bacteria in industrial facilities.
Collapse
Affiliation(s)
- Tatsuki Kunoh
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Tatsuya Yamamoto
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Erika Ono
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Shinya Sugimoto
- Department of Bacteriology, The Jikei University School of Medicine, Tokyo, Japan
- Jikei Center for Biofilm Science and Technology, The Jikei University School of Medicine, Tokyo, Japan
| | - Kyosuke Takabe
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Minoru Takeda
- Division of Materials Science and Chemical Engineering, Faculty of Engineering, Yokohama National University, Yokohama, Kanagawa, Japan
| | - Andrew S. Utada
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
- Microbiology Research Center for Sustainability, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Nobuhiko Nomura
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
- Microbiology Research Center for Sustainability, University of Tsukuba, Tsukuba, Ibaraki, Japan
| |
Collapse
|
12
|
Matta AJ, Zambrano DC, Martínez YC, Fernández FF. Point mutations in the glycosyltransferase domain of the pbp1a gene in amoxicillin-resistant Helicobacter pylori isolates. REVISTA DE GASTROENTEROLOGIA DE MEXICO (ENGLISH) 2023; 88:100-106. [PMID: 35661638 DOI: 10.1016/j.rgmxen.2021.05.015] [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: 08/09/2020] [Accepted: 05/14/2021] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Helicobacter pylori (H. pylori) eradication treatment includes a proton pump inhibitor and two antibiotics: amoxicillin and clarithromycin. The goal of that treatment is to eradicate the infection in at least 90% of the patients. Failure to eradicate the infection can have multiple causes, among which is the presence of point mutations in the antimicrobial target genes. OBJECTIVE To characterize the mutations present in the pbp1a gene and their possible association with resistance to amoxicillin in vitro. METHODOLOGY Susceptibility to amoxicillin was evaluated in 147 isolates of H. pylori from the Colombian municipality of Túquerres. PCR amplification and sequencing of the glycosyltransferase domain of the pbp1a gene were carried out on Túquerres isolates, and the association between mutations and resistance was evaluated. RESULTS A total of 5.4% (8/147) Túquerres isolates were resistant to amoxicillin in vitro. PCR amplification of the glycosyltransferase domain of the pbp1A gene was performed on 87.5% of the amoxicillin-resistant isolates in vitro, and in the DNA sequencing analysis, a total of 2 changes of amino acids from 3 DNA mutations that encoded the PBP1A-1 protein were observed. CONCLUSION The present study is the first report on pbp1a gene mutations in H. pylori isolates coming from a population in Túquerres. Mutations that have not been reported in previous studies were found.
Collapse
Affiliation(s)
- A J Matta
- Facultad de Ciencias de la Educación y el Deporte, Escuela Nacional del Deporte, Cali, Colombia
| | - D C Zambrano
- Facultad de Ciencias de la Educación y el Deporte, Escuela Nacional del Deporte, Cali, Colombia
| | - Y C Martínez
- Facultad de Salud, Escuela de Medicina, Corporación Universitaria Rafael Núñez, Cartagena de Indias, Colombia
| | - F F Fernández
- Facultad de Ciencias, Universidad San Buenaventura, Cali, Colombia.
| |
Collapse
|
13
|
Liang Y, Zhao Y, Kwan J, Wang Y, Qiao Y. Escherichia coli has robust regulatory mechanisms against elevated peptidoglycan cleavage by lytic transglycosylases. J Biol Chem 2023; 299:104615. [PMID: 36931392 PMCID: PMC10139938 DOI: 10.1016/j.jbc.2023.104615] [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: 12/19/2022] [Revised: 02/25/2023] [Accepted: 03/09/2023] [Indexed: 03/17/2023] Open
Abstract
Peptidoglycan (PG) is an essential and conserved exoskeletal component in all bacteria that protects cells from lysis. Gram-negative bacteria such as Escherichia coli encode multiple redundant lytic transglycosylases (LTs) that engage in PG cleavage, a potentially lethal activity requiring proper regulation to prevent autolysis. To elucidate the potential effects and cellular regulatory mechanisms of elevated LT activity, we individually cloned the periplasmic domains of two membrane-bound LTs, MltA and MltB under the control of the arabinose-inducible system for overexpression in the periplasmic space in E. coli. Interestingly, upon induction, the culture undergoes an initial period of cell lysis followed by robust growth restoration. The LT-overexpressing E. coli exhibits altered morphology with larger spherical cells, which is in line with the weakening of the PG layer due to aberrant LT activity. On the other hand, the restored cells display a similar rod shape and peptidoglycan profile that is indistinguishable from the uninduced control. Quantitative proteomics analysis of the restored cells identified significant protein enrichment in the regulator of capsule synthesis (Rcs) regulon, a two-component stress response known to be specifically activated by PG damage. We showed that LT-overexpressing E. coli with an inactivated Rcs system partially impairs the growth restoration process, supporting the involvement of the Rcs system in countering aberrant PG cleavage. Furthermore, we demonstrated that the elevated LT activity specifically potentiates β-lactam antibiotics against E. coli with a defective Rcs regulon, suggesting the dual effects of augmented PG cleavage and blocked PG synthesis as a potential antimicrobial strategy.
Collapse
Affiliation(s)
- Yaquan Liang
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technical University, Singapore 637371
| | - Yilin Zhao
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technical University, Singapore 637371
| | - JericMunChung Kwan
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technical University, Singapore 637371
| | - Yue Wang
- A*STAR Infectious Disease Labs, Singapore 138648
| | - Yuan Qiao
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technical University, Singapore 637371.
| |
Collapse
|
14
|
Tian D, Wang C, Liu Y, Zhang Y, Caliari A, Lu H, Xia Y, Xu B, Xu J, Yomo T. Cell Sorting-Directed Selection of Bacterial Cells in Bigger Sizes Analyzed by Imaging Flow Cytometry during Experimental Evolution. Int J Mol Sci 2023; 24:ijms24043243. [PMID: 36834655 PMCID: PMC9966196 DOI: 10.3390/ijms24043243] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/20/2023] [Accepted: 01/26/2023] [Indexed: 02/10/2023] Open
Abstract
Cell morphology is an essential and phenotypic trait that can be easily tracked during adaptation and evolution to environmental changes. Thanks to the rapid development of quantitative analytical techniques for large populations of cells based on their optical properties, morphology can be easily determined and tracked during experimental evolution. Furthermore, the directed evolution of new culturable morphological phenotypes can find use in synthetic biology to refine fermentation processes. It remains unknown whether and how fast we can obtain a stable mutant with distinct morphologies using fluorescence-activated cell sorting (FACS)-directed experimental evolution. Taking advantage of FACS and imaging flow cytometry (IFC), we direct the experimental evolution of the E. coli population undergoing continuous passage of sorted cells with specific optical properties. After ten rounds of sorting and culturing, a lineage with large cells resulting from incomplete closure of the division ring was obtained. Genome sequencing highlighted a stop-gain mutation in amiC, leading to a dysfunctional AmiC division protein. The combination of FACS-based selection with IFC analysis to track the evolution of the bacteria population in real-time holds promise to rapidly select and culture new morphologies and association tendencies with many potential applications.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Jian Xu
- Correspondence: (J.X.); (T.Y.); Tel.: +86-(21)-62233727 (J.X. & T.Y.)
| | - Tetsuya Yomo
- Correspondence: (J.X.); (T.Y.); Tel.: +86-(21)-62233727 (J.X. & T.Y.)
| |
Collapse
|
15
|
Nikolic P, Mudgil P. The Cell Wall, Cell Membrane and Virulence Factors of Staphylococcus aureus and Their Role in Antibiotic Resistance. Microorganisms 2023; 11:microorganisms11020259. [PMID: 36838224 PMCID: PMC9965861 DOI: 10.3390/microorganisms11020259] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023] Open
Abstract
Antibiotic resistant strains of bacteria are a serious threat to human health. With increasing antibiotic resistance in common human pathogens, fewer antibiotics remain effective against infectious diseases. Staphylococcus aureus is a pathogenic bacterium of particular concern to human health as it has developed resistance to many of the currently used antibiotics leaving very few remaining as effective treatment. Alternatives to conventional antibiotics are needed for treating resistant bacterial infections. A deeper understanding of the cellular characteristics of resistant bacteria beyond well characterized resistance mechanisms can allow for increased ability to properly treat them and to potentially identify targetable changes. This review looks at antibiotic resistance in S aureus in relation to its cellular components, the cell wall, cell membrane and virulence factors. Methicillin resistant S aureus bacteria are resistant to most antibiotics and some strains have even developed resistance to the last resort antibiotics vancomycin and daptomycin. Modifications in cell wall peptidoglycan and teichoic acids are noted in antibiotic resistant bacteria. Alterations in cell membrane lipids affect susceptibility to antibiotics through surface charge, permeability, fluidity, and stability of the bacterial membrane. Virulence factors such as adhesins, toxins and immunomodulators serve versatile pathogenic functions in S aureus. New antimicrobial strategies can target cell membrane lipids and virulence factors including anti-virulence treatment as an adjuvant to traditional antibiotic therapy.
Collapse
|
16
|
Zhang X, Huang Z, Zhong Z, Li Q, Bian F, Yang C. Metagenomic insights into the characteristics of soil microbial communities in the decomposing biomass of Moso bamboo forests under different management practices. Front Microbiol 2022; 13:1051721. [PMID: 36590390 PMCID: PMC9797724 DOI: 10.3389/fmicb.2022.1051721] [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: 09/23/2022] [Accepted: 11/22/2022] [Indexed: 12/23/2022] Open
Abstract
Introduction Considering the rapid growth and high biomass productivity, Moso bamboo (Phyllostachys edulis) has high carbon (C) sequestration potential, and different management practices can strongly modify its C pools. Soil microorganisms play an important role in C turnover through dead plant and microbial biomass degradation. To date, little is known about how different management practices affect microbial carbohydrate-active enzymes (CAZymes) and their responses to dead biomass degradation. Methods Based on metagenomics analysis, this study analyzed CAZymes in three comparable stands from each Moso bamboo plantation: undisturbed (M0), extensively managed (M1), and intensively managed (M2). Results The results showed that the number of CAZymes encoding plant-derived component degradation was higher than that encoding microbe-derived component degradation. Compared with the M0, the CAZyme families encoding plant-derived cellulose were significantly (p < 0.05) high in M2 and significantly (p < 0.05) low in M1. For microbe-derived components, the abundance of CAZymes involved in the bacterial-derived peptidoglycan was higher than that in fungal-derived components (chitin and glucans). Furthermore, M2 significantly increased the fungal-derived chitin and bacterial-derived peptidoglycan compared to M0, whereas M1 significantly decreased the fungal-derived glucans and significantly increased the bacterial-derived peptidoglycan. Four bacterial phyla (Acidobacteria, Actinobacteria, Proteobacteria, and Chloroflexi) mainly contributed to the degradation of C sources from the plant and microbial biomass. Redundancy analysis (RDA) and mantel test suggested the abundance of CAZyme encoding genes for plant and microbial biomass degradation are significantly correlated with soil pH, total P, and available K. Least Squares Path Modeling (PLS-PM) showed that management practices indirectly affect the CAZyme encoding genes associated with plant and microbial biomass degradation by regulating the soil pH and nutrients (total N and P), respectively. Discussion Our study established that M2 and M1 impact dead biomass decomposition and C turnover, contributing to decreased C accumulation and establishing that the bacterial community plays the main role in C turnover in bamboo plantations.
Collapse
Affiliation(s)
- Xiaoping Zhang
- Key Laboratory of Bamboo Forest Ecology and Resource Utilization of National Forestry and Grassland Administration, China National Bamboo Research Center, Zhejiang, China,National Long-term Observation and Research Station for Forest Ecosystem in Hangzhou-Jiaxing-Huzhou Plain, Zhejiang, China,Engineering Research Center of Biochar of Zhejiang Province, Zhejiang, China
| | - Zhiyuan Huang
- Key Laboratory of Bamboo Forest Ecology and Resource Utilization of National Forestry and Grassland Administration, China National Bamboo Research Center, Zhejiang, China,National Long-term Observation and Research Station for Forest Ecosystem in Hangzhou-Jiaxing-Huzhou Plain, Zhejiang, China
| | - Zheke Zhong
- Key Laboratory of Bamboo Forest Ecology and Resource Utilization of National Forestry and Grassland Administration, China National Bamboo Research Center, Zhejiang, China,National Long-term Observation and Research Station for Forest Ecosystem in Hangzhou-Jiaxing-Huzhou Plain, Zhejiang, China,*Correspondence: Zheke Zhong,
| | - Qiaoling Li
- Key Laboratory of Bamboo Forest Ecology and Resource Utilization of National Forestry and Grassland Administration, China National Bamboo Research Center, Zhejiang, China,National Long-term Observation and Research Station for Forest Ecosystem in Hangzhou-Jiaxing-Huzhou Plain, Zhejiang, China
| | - Fangyuan Bian
- Key Laboratory of Bamboo Forest Ecology and Resource Utilization of National Forestry and Grassland Administration, China National Bamboo Research Center, Zhejiang, China,National Long-term Observation and Research Station for Forest Ecosystem in Hangzhou-Jiaxing-Huzhou Plain, Zhejiang, China
| | - Chuanbao Yang
- Key Laboratory of Bamboo Forest Ecology and Resource Utilization of National Forestry and Grassland Administration, China National Bamboo Research Center, Zhejiang, China,National Long-term Observation and Research Station for Forest Ecosystem in Hangzhou-Jiaxing-Huzhou Plain, Zhejiang, China
| |
Collapse
|
17
|
The Staphylococcus aureus cell division protein, DivIC, interacts with the cell wall and controls its biosynthesis. Commun Biol 2022; 5:1228. [DOI: 10.1038/s42003-022-04161-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 10/24/2022] [Indexed: 11/13/2022] Open
Abstract
AbstractBacterial cell division is a complex, dynamic process that requires multiple protein components to orchestrate its progression. Many division proteins are highly conserved across bacterial species alluding to a common, basic mechanism. Central to division is a transmembrane trimeric complex involving DivIB, DivIC and FtsL in Gram-positives. Here, we show a distinct, essential role for DivIC in division and survival of Staphylococcus aureus. DivIC spatially regulates peptidoglycan synthesis, and consequently cell wall architecture, by influencing the recruitment to the division septum of the major peptidoglycan synthetases PBP2 and FtsW. Both the function of DivIC and its recruitment to the division site depend on its extracellular domain, which interacts with the cell wall via binding to wall teichoic acids. DivIC facilitates the spatial and temporal coordination of peptidoglycan synthesis with the developing architecture of the septum during cell division. A better understanding of the cell division mechanisms in S. aureus and other pathogenic microorganisms can provide possibilities for the development of new, more effective treatments for bacterial infections.
Collapse
|
18
|
López‐Escarpa D, Castanheira S, García‐del Portillo F. OmpR and Prc contribute to switch the Salmonella morphogenetic program in response to phagosome cues. Mol Microbiol 2022; 118:477-493. [PMID: 36115022 PMCID: PMC9827838 DOI: 10.1111/mmi.14982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 09/08/2022] [Accepted: 09/13/2022] [Indexed: 01/12/2023]
Abstract
Salmonella enterica serovar Typhimurium infects eukaryotic cells residing within membrane-bound phagosomes. In this compartment, the pathogen replaces the morphogenetic penicillin-binding proteins 2 and 3 (PBP2/PBP3) with PBP2SAL /PBP3SAL , two proteins absent in Escherichia coli. The basis for this switch is unknown. Here, we show that PBP3 protein levels drop drastically when S. Typhimurium senses acidity, high osmolarity and nutrient scarcity, cues that activate virulence functions required for intra-phagosomal survival and proliferation. The protease Prc and the transcriptional regulator OmpR contribute to lower PBP3 levels whereas OmpR stimulates PBP2SAL /PBP3SAL production. Surprisingly, despite being essential for division in E. coli, PBP3 levels also drop in non-pathogenic and pathogenic E. coli exposed to phagosome cues. Such exposure alters E. coli morphology resulting in very long bent and twisted filaments indicative of failure in the cell division and elongation machineries. None of these aberrant shapes are detected in S. Typhimurium. Expression of PBP3SAL restores cell division in E. coli exposed to phagosome cues although the cells retain elongation defects in the longitudinal axis. By switching the morphogenetic program, OmpR and Prc allow S. Typhimurium to properly divide and elongate inside acidic phagosomes maintaining its cellular dimensions and the rod shape.
Collapse
Affiliation(s)
- David López‐Escarpa
- Laboratory of Intracellular Bacterial PathogensNational Centre for Biotechnology (CNB‐CSIC)MadridSpain
| | - Sónia Castanheira
- Laboratory of Intracellular Bacterial PathogensNational Centre for Biotechnology (CNB‐CSIC)MadridSpain
| | | |
Collapse
|
19
|
Guan S, Yu H, Xiang H, Wang L, Liu J, Wu A, Zheng J, Dong H, Wang L, Wang D. WYBQ-4: a New Bactericidal Agent against Methicillin-Resistant Staphylococcus aureus. Microbiol Spectr 2022; 10:e0054722. [PMID: 36098533 PMCID: PMC9603521 DOI: 10.1128/spectrum.00547-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 08/25/2022] [Indexed: 12/30/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug-resistant pathogen that currently poses a serious threat to global health. Novel antimicrobial agents against MRSA are urgently being developed. In this study, we investigated WYBQ-4, which is an effective antibacterial agent with potent bactericidal activity and bactericidal efficiency against MRSA USA300 and clinical isolate strains. In addition, WYBQ-4 exhibited low cytotoxicity without hemolytic activity according to a safety evaluation. Importantly, WYBQ-4 showed potent in vivo efficacy in an MRSA-induced mouse pneumonia model, systemic infection model, and intramuscular infection model. The efficacy of this new cephalosporin against MRSA was associated with a high affinity for penicillin-binding proteins (PBP1, PBP2, PBP3, PBP4, PBP2a) evaluated in a competition assay using bocillin as a reporter. In conclusion, WYBQ-4 has a significant bactericidal effect in vitro and in vivo, indicating that it is a promising compound to control MRSA infection. IMPORTANCE Antibiotic resistance is spreading faster than the introduction of new compounds into clinical practice, causing a public health crisis. Novel antimicrobial agents against MRSA are urgently being developed. In this study, we investigated WYBQ-4, which is an effective antibacterial agent with potent bacteriostatic activity and bactericidal efficiency against MRSA USA300 and clinical isolate strains. WYBQ-4 showed potent in vivo efficacy in MRSA-induced mouse models. Subsequently, we further revealed its antibacterial mechanism. In conclusion, WYBQ-4 has a significant bactericidal effect in vitro and in vivo, indicating that it is a promising compound to control MRSA infection.
Collapse
Affiliation(s)
- Shuhan Guan
- College of Animal Science, Jilin University, Changchun, China
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun, China
| | - Hangqian Yu
- College of Animal Science, Jilin University, Changchun, China
| | - Hua Xiang
- College of Animal Medicine, Jilin Agricultural University, Changchun, China
| | - Li Wang
- College of Animal Science, Jilin University, Changchun, China
- Changchun University of Chinese Medicine, Changchun, China
| | - Jingyu Liu
- College of Animal Science, Jilin University, Changchun, China
| | - Anfang Wu
- College of Animal Science, Jilin University, Changchun, China
| | - Jianze Zheng
- College of Animal Science, Jilin University, Changchun, China
| | - Hongbo Dong
- School of Pharmacy, Chengdu University, Chengdu, China
| | - Lin Wang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun, China
| | - Dacheng Wang
- College of Animal Science, Jilin University, Changchun, China
| |
Collapse
|
20
|
Jalalvand F, Su YC, Manat G, Chernobrovkin A, Kadari M, Jonsson S, Janousková M, Rutishauser D, Semsey S, Løbner-Olesen A, Sandblad L, Flärdh K, Mengin-Lecreulx D, Zubarev RA, Riesbeck K. Protein domain-dependent vesiculation of Lipoprotein A, a protein that is important in cell wall synthesis and fitness of the human respiratory pathogen Haemophilus influenzae. Front Cell Infect Microbiol 2022; 12:984955. [PMID: 36275016 PMCID: PMC9585305 DOI: 10.3389/fcimb.2022.984955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 09/15/2022] [Indexed: 11/13/2022] Open
Abstract
The human pathogen Haemophilus influenzae causes respiratory tract infections and is commonly associated with prolonged carriage in patients with chronic obstructive pulmonary disease. Production of outer membrane vesicles (OMVs) is a ubiquitous phenomenon observed in Gram-negative bacteria including H. influenzae. OMVs play an important role in various interactions with the human host; from neutralization of antibodies and complement activation to spread of antimicrobial resistance. Upon vesiculation certain proteins are found in OMVs and some proteins are retained at the cell membrane. The mechanism for this phenomenon is not fully elucidated. We employed mass spectrometry to study vesiculation and the fate of proteins in the outer membrane. Functional groups of proteins were differentially distributed on the cell surface and in OMVs. Despite its supposedly periplasmic and outer membrane location, we found that the peptidoglycan synthase-activator Lipoprotein A (LpoA) was accumulated in OMVs relative to membrane fractions. A mutant devoid of LpoA lost its fitness as revealed by growth and electron microscopy. Furthermore, high-pressure liquid chromatography disclosed a lower concentration (55%) of peptidoglycan in the LpoA-deficient H. influenzae compared to the parent wild type bacterium. Using an LpoA-mNeonGreen fusion protein and fluorescence microscopy, we observed that LpoA was enriched in “foci” in the cell envelope, and further located in the septum during cell division. To define the fate of LpoA, C-terminally truncated LpoA-variants were constructed, and we found that the LpoA C-terminal domain promoted optimal transportation to the OMVs as revealed by flow cytometry. Taken together, our study highlights the importance of LpoA for H. influenzae peptidoglycan biogenesis and provides novel insights into cell wall integrity and OMV production.
Collapse
Affiliation(s)
- Farshid Jalalvand
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Yu-Ching Su
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Guillaume Manat
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Alexey Chernobrovkin
- Physiological Chemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Mahendar Kadari
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Sandra Jonsson
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Martina Janousková
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Dorothea Rutishauser
- Physiological Chemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Szabolcs Semsey
- Centre for Bacterial Stress Response and Persistence, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Anders Løbner-Olesen
- Centre for Bacterial Stress Response and Persistence, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | | | - Klas Flärdh
- Department of Biology, Lund University, Lund, Sweden
| | - Dominique Mengin-Lecreulx
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Roman A. Zubarev
- Physiological Chemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Kristian Riesbeck
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
- *Correspondence: Kristian Riesbeck,
| |
Collapse
|
21
|
Combination with a FtsZ inhibitor potentiates the in vivo efficacy of oxacillin against methicillin-resistant Staphylococcus aureus. Med Chem Res 2022; 31:1705-1715. [PMID: 37065467 PMCID: PMC10104549 DOI: 10.1007/s00044-022-02960-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Oxacillin is a first-line antibiotic for the treatment of methicillin-sensitive Staphylococcus aureus (MSSA) infections but is ineffective against methicillin-resistant S. aureus (MRSA) due to resistance. Here we present results showing that co-administering oxacillin with the FtsZ-targeting prodrug TXA709 renders oxacillin efficacious against MRSA. The combination of oxacillin and the active product of TXA709 (TXA707) is associated with synergistic bactericidal activity against clinical isolates of MRSA that are resistant to current standard-of-care antibiotics. We show that MRSA cells treated with oxacillin in combination with TXA707 exhibit morphological characteristics and PBP2 mislocalization behavior similar to that exhibited by MSSA cells treated with oxacillin alone. Co-administration with TXA709 renders oxacillin efficacious in mouse models of both systemic and tissue infection with MRSA, with this efficacy being observed at human-equivalent doses of oxacillin well below that recommended for daily adult use. Pharmacokinetic evaluations in mice reveal that co-administration with TXA709 also increases total exposure to oxacillin. Viewed as a whole, our results highlight the clinical potential of repurposing oxacillin to treat MRSA infections through combination with a FtsZ inhibitor.
Collapse
|
22
|
Xu Y, Hernández-Rocamora VM, Lorent JH, Cox R, Wang X, Bao X, Stel M, Vos G, van den Bos RM, Pieters RJ, Gray J, Vollmer W, Breukink E. Metabolic labeling of the bacterial peptidoglycan by functionalized glucosamine. iScience 2022; 25:104753. [PMID: 35942089 PMCID: PMC9356107 DOI: 10.1016/j.isci.2022.104753] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/09/2022] [Accepted: 07/08/2022] [Indexed: 11/28/2022] Open
Abstract
N-Acetylglucosamine (GlcNAc) is an essential monosaccharide required in almost all organisms. Fluorescent labeling of the peptidoglycan (PG) on N-acetylglucosamine has been poorly explored. Here, we report on the labeling of the PG with a bioorthogonal handle on the GlcNAc. We developed a facile one-step synthesis of uridine diphosphate N-azidoacetylglucosamine (UDP-GlcNAz) using the glycosyltransferase OleD, followed by in vitro incorporation of GlcNAz into the peptidoglycan precursor Lipid II and fluorescent labeling of the azido group via click chemistry. In a PG synthesis assay, fluorescent GlcNAz-labeled Lipid II was incorporated into peptidoglycan by the DD-transpeptidase activity of bifunctional class A penicillin-binding proteins. We further demonstrate the incorporation of GlcNAz into the PG layer of OleD-expressed bacteria by feeding with 2-chloro-4-nitrophenyl GlcNAz (GlcNAz-CNP). Hence, our labeling method using the heterologous expression of OleD is useful to study PG synthesis and possibly other biological processes involving GlcNAc metabolism in vivo. Peptidoglycan consists of N-acetylglucosamine, N-acetylmuramic acid, and amino acids We developed a one-step synthesis of azide-labeled UDP-N-acetylglucosamine In vivo generated azide-labeled UDP-N-acetylglucosamine gets incorporated into peptidoglycan Bacteria were fluorescently labeled on N-acetylglucosamine of peptidoglycan
Collapse
Affiliation(s)
- Yang Xu
- Membrane Biochemistry and Biophysics, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Utrecht University, Padualaan 8, 3584 Utrecht, the Netherlands
| | | | - Joseph H. Lorent
- Membrane Biochemistry and Biophysics, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Utrecht University, Padualaan 8, 3584 Utrecht, the Netherlands
| | - Ruud Cox
- Membrane Biochemistry and Biophysics, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Utrecht University, Padualaan 8, 3584 Utrecht, the Netherlands
| | - Xiaoqi Wang
- Membrane Biochemistry and Biophysics, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Utrecht University, Padualaan 8, 3584 Utrecht, the Netherlands
| | - Xue Bao
- Membrane Biochemistry and Biophysics, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Utrecht University, Padualaan 8, 3584 Utrecht, the Netherlands
| | - Marjon Stel
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Universiteitsweg 99, 3584 Utrecht, the Netherlands
| | - Gaël Vos
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Universiteitsweg 99, 3584 Utrecht, the Netherlands
| | - Ramon M. van den Bos
- Membrane Biochemistry and Biophysics, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Utrecht University, Padualaan 8, 3584 Utrecht, the Netherlands
| | - Roland J. Pieters
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Universiteitsweg 99, 3584 Utrecht, the Netherlands
| | - Joe Gray
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Eefjan Breukink
- Membrane Biochemistry and Biophysics, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Utrecht University, Padualaan 8, 3584 Utrecht, the Netherlands
- Corresponding author
| |
Collapse
|
23
|
Wang M, Buist G, van Dijl JM. Staphylococcus aureus cell wall maintenance - the multifaceted roles of peptidoglycan hydrolases in bacterial growth, fitness, and virulence. FEMS Microbiol Rev 2022; 46:6604383. [PMID: 35675307 PMCID: PMC9616470 DOI: 10.1093/femsre/fuac025] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 04/22/2022] [Accepted: 05/25/2022] [Indexed: 01/07/2023] Open
Abstract
Staphylococcus aureus is an important human and livestock pathogen that is well-protected against environmental insults by a thick cell wall. Accordingly, the wall is a major target of present-day antimicrobial therapy. Unfortunately, S. aureus has mastered the art of antimicrobial resistance, as underscored by the global spread of methicillin-resistant S. aureus (MRSA). The major cell wall component is peptidoglycan. Importantly, the peptidoglycan network is not only vital for cell wall function, but it also represents a bacterial Achilles' heel. In particular, this network is continuously opened by no less than 18 different peptidoglycan hydrolases (PGHs) encoded by the S. aureus core genome, which facilitate bacterial growth and division. This focuses attention on the specific functions executed by these enzymes, their subcellular localization, their control at the transcriptional and post-transcriptional levels, their contributions to staphylococcal virulence and their overall importance in bacterial homeostasis. As highlighted in the present review, our understanding of the different aspects of PGH function in S. aureus has been substantially increased over recent years. This is important because it opens up new possibilities to exploit PGHs as innovative targets for next-generation antimicrobials, passive or active immunization strategies, or even to engineer them into effective antimicrobial agents.
Collapse
Affiliation(s)
- Min Wang
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, PO Box 30001, 9700 RB Groningen, the Netherlands
| | | | - Jan Maarten van Dijl
- Corresponding author: Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, P.O. box 30001, HPC EB80, 9700 RB Groningen, the Netherlands, Tel. +31-50-3615187; Fax. +31-50-3619105; E-mail:
| |
Collapse
|
24
|
Induction of AmpC-Mediated β-Lactam Resistance Requires a Single Lytic Transglycosylase in Agrobacterium tumefaciens. Appl Environ Microbiol 2022; 88:e0033322. [PMID: 35638841 PMCID: PMC9238390 DOI: 10.1128/aem.00333-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The remarkable ability of Agrobacterium tumefaciens to transfer DNA to plant cells has allowed the generation of important transgenic crops. One challenge of A. tumefaciens-mediated transformation is eliminating the bacteria after plant transformation to prevent detrimental effects to plants and the release of engineered bacteria to the environment. Here, we use a reverse-genetics approach to identify genes involved in ampicillin resistance, with the goal of utilizing these antibiotic-sensitive strains for plant transformations. We show that treating A. tumefaciens C58 with ampicillin led to increased β-lactamase production, a response dependent on the broad-spectrum β-lactamase AmpC and its transcription factor, AmpR. Loss of the putative ampD orthologue atu2113 led to constitutive production of AmpC-dependent β-lactamase activity and ampicillin resistance. Finally, one cell wall remodeling enzyme, MltB3, was necessary for the AmpC-dependent β-lactamase activity, and its loss elicited ampicillin and carbenicillin sensitivity in the A. tumefaciens C58 and GV3101 strains. Furthermore, GV3101 ΔmltB3 transforms plants with efficiency comparable to that of the wild type but can be cleared with sublethal concentrations of ampicillin. The functional characterization of the genes involved in the inducible ampicillin resistance pathway of A. tumefaciens constitutes a major step forward in efforts to reduce the intrinsic antibiotic resistance of this bacterium. IMPORTANCE Agrobacterium tumefaciens, a significant biotechnological tool for production of transgenic plant lines, is highly resistant to a wide variety of antibiotics, posing challenges for various applications. One challenge is the efficient elimination of A. tumefaciens from transformed plant tissue without using levels of antibiotics that are toxic to the plants. Here, we present the functional characterization of genes involved in β-lactam resistance in A. tumefaciens. Knowledge about proteins that promote or inhibit β-lactam resistance will enable the development of strains to improve the efficiency of Agrobacterium-mediated plant genetic transformations. Effective removal of Agrobacterium from transformed plant tissue has the potential to maximize crop yield and food production, improving the outlook for global food security.
Collapse
|
25
|
Selim S, Faried OA, Almuhayawi MS, Mohammed OA, Saleh FM, Warrad M. Dynamic Gene Clusters Mediating Carbapenem-Resistant Acinetobacter baumannii Clinical Isolates. Antibiotics (Basel) 2022; 11:antibiotics11020168. [PMID: 35203771 PMCID: PMC8868416 DOI: 10.3390/antibiotics11020168] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 02/04/2023] Open
Abstract
Acinetobacter baumanni (A. baumannii), a nonfermenting Gram-negative bacterium, has recently been associated with a broad range of nosocomial infections. To gain more meaningful insight into the problem of nosocomial illnesses caused by the multidrug-resistant (MDR) A. baumannii, as well as the factors that increase the risk of catching these infections, this investigation included a total of 86 clinical A. baumannii infections. Repetitive extragenic palindromic (REP)-PCR was used to investigate imipenem-resistant A. baumannii isolates for dynamic gene clusters causing carbapenem resistance. Four distinct A. baumannii lineages were found in the REP-PCR-DNA fingerprints of all isolates, with 95% of the samples coming from two dominant lineages. Imipenem, amikacin, and ciprofloxacin were less effective against genotype (A) isolates because of enhanced antibiotic tolerance. Lastly, to gain more insight into the mode of action of imipenem, we explored the binding affinity of imipenem toward different Acinetobacter baumannii OXA beta-lactamase class enzymes.
Collapse
Affiliation(s)
- Samy Selim
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Sakaka 72341, Saudi Arabia
- Correspondence:
| | - Osama Ahmed Faried
- Medical Microbiology and Immunology Department, Faculty of Medicine, Beni-Suef University, Beni-Suef 62513, Egypt;
| | - Mohamed S. Almuhayawi
- Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
| | - Osama A. Mohammed
- Department of Clinical Pharmacology, Faculty of Medicine, Ain Shams University, Cairo 11566, Egypt;
- Department of Clinical Pharmacology, Faculty of Medicine, Bisha University, Bisha 61922, Saudi Arabia
| | - Fayez M. Saleh
- Department of Medical Microbiology, Faculty of Medicine, University of Tabuk, Tabuk 71491, Saudi Arabia;
| | - Mona Warrad
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences at Al-Quriat, Jouf University, Al-Quriat 77454, Saudi Arabia;
| |
Collapse
|
26
|
Designing a novel in-silico multi-epitope vaccine against penicillin-binding protein 2A in Staphylococcus aureus. INFORMATICS IN MEDICINE UNLOCKED 2022. [DOI: 10.1016/j.imu.2022.101080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
27
|
Bright R, Fernandes D, Wood J, Palms D, Burzava A, Ninan N, Brown T, Barker D, Vasilev K. Long-term antibacterial properties of a nanostructured titanium alloy surface: An in vitro study. Mater Today Bio 2021; 13:100176. [PMID: 34938990 DOI: 10.1016/j.mtbio.2021.100176] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/18/2021] [Accepted: 12/01/2021] [Indexed: 12/31/2022] Open
Abstract
The demand for joint replacement and other orthopedic surgeries involving titanium implants is continuously increasing; however, 1%-2% of surgeries result in costly and devastating implant associated infections (IAIs). Pseudomonas aeruginosa and Staphylococcus aureus are two common pathogens known to colonise implants, leading to serious complications. Bioinspired surfaces with spike-like nanotopography have previously been shown to kill bacteria upon contact; however, the longer-term potential of such surfaces to prevent or delay biofilm formation is unclear. Hence, we monitored biofilm formation on control and nanostructured titanium disc surfaces over 21 days following inoculation with Pseudomonas aeruginosa and Staphylococcus aureus. We found a consistent 2-log or higher reduction in live bacteria throughout the time course for both bacteria. The biovolume on nanostructured discs was also significantly lower than control discs at all time points for both bacteria. Analysis of the biovolume revealed that for the nanostructured surface, bacteria was killed not just on the surface, but at locations above the surface. Interestingly, pockets of bacterial regrowth on top of the biomass occurred in both bacterial species, however this was more pronounced for S. aureus cultures after 21 days. We found that the nanostructured surface showed antibacterial properties throughout this longitudinal study. To our knowledge this is the first in vitro study to show reduction in the viability of bacterial colonisation on a nanostructured surface over a clinically relevant time frame, providing potential to reduce the likelihood of implant associated infections.
Collapse
Affiliation(s)
- Richard Bright
- Academic Unit of STEM, University of South Australia, Mawson Lakes, Adelaide, 5095, South Australia, Australia
| | - Daniel Fernandes
- Academic Unit of STEM, University of South Australia, Mawson Lakes, Adelaide, 5095, South Australia, Australia
| | - Jonathan Wood
- Academic Unit of STEM, University of South Australia, Mawson Lakes, Adelaide, 5095, South Australia, Australia
| | - Dennis Palms
- Academic Unit of STEM, University of South Australia, Mawson Lakes, Adelaide, 5095, South Australia, Australia
| | - Anouck Burzava
- Academic Unit of STEM, University of South Australia, Mawson Lakes, Adelaide, 5095, South Australia, Australia
| | - Neethu Ninan
- Academic Unit of STEM, University of South Australia, Mawson Lakes, Adelaide, 5095, South Australia, Australia
| | - Toby Brown
- Corin Australia, Pymble, NSW 2073, Australia
| | - Dan Barker
- Corin Australia, Pymble, NSW 2073, Australia
| | - Krasimir Vasilev
- Academic Unit of STEM, University of South Australia, Mawson Lakes, Adelaide, 5095, South Australia, Australia
| |
Collapse
|
28
|
Graham CLB, Newman H, Gillett FN, Smart K, Briggs N, Banzhaf M, Roper DI. A Dynamic Network of Proteins Facilitate Cell Envelope Biogenesis in Gram-Negative Bacteria. Int J Mol Sci 2021; 22:12831. [PMID: 34884635 PMCID: PMC8657477 DOI: 10.3390/ijms222312831] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 01/01/2023] Open
Abstract
Bacteria must maintain the ability to modify and repair the peptidoglycan layer without jeopardising its essential functions in cell shape, cellular integrity and intermolecular interactions. A range of new experimental techniques is bringing an advanced understanding of how bacteria regulate and achieve peptidoglycan synthesis, particularly in respect of the central role played by complexes of Sporulation, Elongation or Division (SEDs) and class B penicillin-binding proteins required for cell division, growth and shape. In this review we highlight relationships implicated by a bioinformatic approach between the outer membrane, cytoskeletal components, periplasmic control proteins, and cell elongation/division proteins to provide further perspective on the interactions of these cell division, growth and shape complexes. We detail the network of protein interactions that assist in the formation of peptidoglycan and highlight the increasingly dynamic and connected set of protein machinery and macrostructures that assist in creating the cell envelope layers in Gram-negative bacteria.
Collapse
Affiliation(s)
- Chris L. B. Graham
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK; (C.L.B.G.); (H.N.); (F.N.G.); (K.S.); (N.B.)
| | - Hector Newman
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK; (C.L.B.G.); (H.N.); (F.N.G.); (K.S.); (N.B.)
| | - Francesca N. Gillett
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK; (C.L.B.G.); (H.N.); (F.N.G.); (K.S.); (N.B.)
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK;
| | - Katie Smart
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK; (C.L.B.G.); (H.N.); (F.N.G.); (K.S.); (N.B.)
| | - Nicholas Briggs
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK; (C.L.B.G.); (H.N.); (F.N.G.); (K.S.); (N.B.)
| | - Manuel Banzhaf
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK;
| | - David I. Roper
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK; (C.L.B.G.); (H.N.); (F.N.G.); (K.S.); (N.B.)
| |
Collapse
|
29
|
Tripathi AK, Thakur P, Saxena P, Rauniyar S, Gopalakrishnan V, Singh RN, Gadhamshetty V, Gnimpieba EZ, Jasthi BK, Sani RK. Gene Sets and Mechanisms of Sulfate-Reducing Bacteria Biofilm Formation and Quorum Sensing With Impact on Corrosion. Front Microbiol 2021; 12:754140. [PMID: 34777309 PMCID: PMC8586430 DOI: 10.3389/fmicb.2021.754140] [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: 08/06/2021] [Accepted: 09/24/2021] [Indexed: 01/02/2023] Open
Abstract
Sulfate-reducing bacteria (SRB) have a unique ability to respire under anaerobic conditions using sulfate as a terminal electron acceptor, reducing it to hydrogen sulfide. SRB thrives in many natural environments (freshwater sediments and salty marshes), deep subsurface environments (oil wells and hydrothermal vents), and processing facilities in an industrial setting. Owing to their ability to alter the physicochemical properties of underlying metals, SRB can induce fouling, corrosion, and pipeline clogging challenges. Indigenous SRB causes oil souring and associated product loss and, subsequently, the abandonment of impacted oil wells. The sessile cells in biofilms are 1,000 times more resistant to biocides and induce 100-fold greater corrosion than their planktonic counterparts. To effectively combat the challenges posed by SRB, it is essential to understand their molecular mechanisms of biofilm formation and corrosion. Here, we examine the critical genes involved in biofilm formation and microbiologically influenced corrosion and categorize them into various functional categories. The current effort also discusses chemical and biological methods for controlling the SRB biofilms. Finally, we highlight the importance of surface engineering approaches for controlling biofilm formation on underlying metal surfaces.
Collapse
Affiliation(s)
- Abhilash Kumar Tripathi
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States.,2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD, United States
| | - Payal Thakur
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD, United States
| | - Priya Saxena
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD, United States
| | - Shailabh Rauniyar
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States.,2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD, United States
| | - Vinoj Gopalakrishnan
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD, United States
| | - Ram Nageena Singh
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States.,2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD, United States
| | - Venkataramana Gadhamshetty
- 2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD, United States.,BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Department of Civil and Environmental Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States
| | - Etienne Z Gnimpieba
- 2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Biomedical Engineering Program, University of South Dakota, Sioux Falls, SD, United States
| | - Bharat K Jasthi
- 2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Department of Materials and Metallurgical Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States
| | - Rajesh Kumar Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States.,2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, SD, United States.,BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD, United States.,Composite and Nanocomposite Advanced Manufacturing Centre-Biomaterials, Rapid City, SD, United States
| |
Collapse
|
30
|
Looks can be deceiving: Bacterial enzymes work through unanticipated mechanism. Proc Natl Acad Sci U S A 2021; 118:2114568118. [PMID: 34526405 DOI: 10.1073/pnas.2114568118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2021] [Indexed: 11/18/2022] Open
|
31
|
A modified approach for high-quality RNA extraction of spore-forming Bacillus subtilis at varied physiological stages. Mol Biol Rep 2021; 48:6757-6768. [PMID: 34455533 DOI: 10.1007/s11033-021-06673-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/18/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND High quality RNA is required for the molecular study. Sample preparation of the spore-forming, Gram-positive bacteria like Bacillus sp., remains challenging although several methods have been proposed. Those techniques were simply developed using cell samples at certain growth stages despite some molecular studies like transcriptomic analyses require RNA samples from different physiological stages. METHODS AND RESULTS We developed the rapid, simple yet effective cell-lysis technique with limit use of harsh reagents by modifying the kit-based protocols. Appropriate lysozyme loading (20 mg/mL), incubation time (30 min), and temperature (37 °C) enabled cell lysis and enhanced RNA extraction from both vegetative cells and endospores of Bacillus subtilis TL7-3. High RNA Integrity Numbers and ratios of A260/A280 and A260/A230 of all RNA products collected during the batch cultivation confirmed that invert mixing with absolute ethanol prevented RNA damage during protein denaturation. With the process modification of the major steps in cell lysis and RNA extraction compared with the kit-based protocols that are typically used in laboratory work, interestingly, our modified protocol, simple-yet-effective, yielded higher concentration, purity, and integrity of RNA products from all cell samples collected at different physiological stages. While the kit-based protocols either failed to provide high RNA concentration or RNA purity and integrity for all cell samples particularly during the late-log, stationary, or sporulation. CONCLUSIONS Therefore, we can claim the significance of this modified protocol to be applicable for RNA extraction to those spore-forming Gram-positive bacteria not limited to B. subtilis growing at varied physiological stages.
Collapse
|
32
|
Schätzle H, Arévalo S, Flores E, Schleiff E. A TonB-Like Protein, SjdR, Is Involved in the Structural Definition of the Intercellular Septa in the Heterocyst-Forming Cyanobacterium Anabaena. mBio 2021; 12:e0048321. [PMID: 34101487 PMCID: PMC8262864 DOI: 10.1128/mbio.00483-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 05/04/2021] [Indexed: 12/11/2022] Open
Abstract
Cyanobacteria are photosynthetic organisms with a Gram-negative envelope structure. Certain filamentous species such as Anabaena sp. strain PCC 7120 can fix dinitrogen upon depletion of combined nitrogen. Because the nitrogen-fixing enzyme, nitrogenase, is oxygen sensitive, photosynthesis and nitrogen fixation are spatially separated in Anabaena. Nitrogen fixation takes place in specialized cells called heterocysts, which differentiate from vegetative cells. During heterocyst differentiation, a microoxic environment is created by dismantling photosystem II and restructuring the cell wall. Moreover, solute exchange between the different cell types is regulated to limit oxygen influx into the heterocyst. The septal zone containing nanopores for solute exchange is constricted between heterocysts and vegetative cells, and cyanophycin plugs are located at the heterocyst poles. We identified a protein previously annotated as TonB1 that is largely conserved among cyanobacteria. A mutant of the encoding gene formed heterocysts but was impaired in diazotrophic growth. Mutant heterocysts appeared elongated and exhibited abnormal morphological features, including a reduced cyanophycin plug, an enhanced septum size, and a restricted nanopore zone in the septum. In spite of this, the intercellular transfer velocity of the fluorescent marker calcein was increased in the mutant compared to the wild type. Thus, the protein is required for proper formation of septal structures, expanding our emerging understanding of Anabaena peptidoglycan plasticity and intercellular solute exchange, and is therefore renamed SjdR (septal junction disk regulator). Notably, calcium supplementation compensated for the impaired diazotrophic growth and alterations in septal peptidoglycan in the sjdR mutant, emphasizing the importance of calcium for cell wall structure. IMPORTANCE Multicellularity in bacteria confers an improved adaptive capacity to environmental conditions and stresses. This includes an enhanced capability of resource utilization through a distribution of biochemical processes between constituent cells. This specialization results in a mutual dependency of different cell types, as is the case for nitrogen-fixing heterocysts and photosynthetically active vegetative cells in Anabaena. In this cyanobacterium, intercellular solute exchange is facilitated through nanopores in the peptidoglycan between adjacent cells. To ensure functionality of the specialized cells, septal size as well as the position, size, and frequency of nanopores in the septum need to be tightly established. The novel septal junction disk regulator SjdR characterized here is conserved in the cyanobacterial phylum. It influences septal size and septal nanopore distribution. Consequently, its absence severely affects the intercellular communication and the strains' growth capacity under nitrogen depletion. Thus, SjdR is involved in septal structure remodeling in cyanobacteria.
Collapse
Affiliation(s)
- Hannah Schätzle
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
- FIERCE, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Sergio Arévalo
- Instituto de Bioquímica Vegetal y Fotosíntesis, CSIC and Universidad de Sevilla, Seville, Spain
| | - Enrique Flores
- Instituto de Bioquímica Vegetal y Fotosíntesis, CSIC and Universidad de Sevilla, Seville, Spain
| | - Enrico Schleiff
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
- FIERCE, Goethe University Frankfurt, Frankfurt am Main, Germany
- Buchmann Institute for Molecular Life Sciences, Frankfurt am Main, Germany
- Frankfurt Institute for Advanced Studies, Frankfurt am Main, Germany
| |
Collapse
|
33
|
Bhat SV, Price JDW, Dahms TES. AFM-Based Correlative Microscopy Illuminates Human Pathogens. Front Cell Infect Microbiol 2021; 11:655501. [PMID: 34026660 PMCID: PMC8138568 DOI: 10.3389/fcimb.2021.655501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 04/08/2021] [Indexed: 12/25/2022] Open
Abstract
Microbes have an arsenal of virulence factors that contribute to their pathogenicity. A number of challenges remain to fully understand disease transmission, fitness landscape, antimicrobial resistance and host heterogeneity. A variety of tools have been used to address diverse aspects of pathogenicity, from molecular host-pathogen interactions to the mechanisms of disease acquisition and transmission. Current gaps in our knowledge include a more direct understanding of host-pathogen interactions, including signaling at interfaces, and direct phenotypic confirmation of pathogenicity. Correlative microscopy has been gaining traction to address the many challenges currently faced in biomedicine, in particular the combination of optical and atomic force microscopy (AFM). AFM, generates high-resolution surface topographical images, and quantifies mechanical properties at the pN scale under physiologically relevant conditions. When combined with optical microscopy, AFM probes pathogen surfaces and their physical and molecular interaction with host cells, while the various modes of optical microscopy view internal cellular responses of the pathogen and host. Here we review the most recent advances in our understanding of pathogens, recent applications of AFM to the field, how correlative AFM-optical microspectroscopy and microscopy have been used to illuminate pathogenicity and how these methods can reach their full potential for studying host-pathogen interactions.
Collapse
Affiliation(s)
- Supriya V Bhat
- Department of Chemistry and Biochemistry, University of Regina, Regina, SK, Canada
| | - Jared D W Price
- Department of Chemistry and Biochemistry, University of Regina, Regina, SK, Canada
| | - Tanya E S Dahms
- Department of Chemistry and Biochemistry, University of Regina, Regina, SK, Canada
| |
Collapse
|
34
|
Martínez B, Rodríguez A, Kulakauskas S, Chapot-Chartier MP. Cell wall homeostasis in lactic acid bacteria: threats and defences. FEMS Microbiol Rev 2021; 44:538-564. [PMID: 32495833 PMCID: PMC7476776 DOI: 10.1093/femsre/fuaa021] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 06/03/2020] [Indexed: 12/16/2022] Open
Abstract
Lactic acid bacteria (LAB) encompasses industrially relevant bacteria involved in food fermentations as well as health-promoting members of our autochthonous microbiota. In the last years, we have witnessed major progresses in the knowledge of the biology of their cell wall, the outermost macrostructure of a Gram-positive cell, which is crucial for survival. Sophisticated biochemical analyses combined with mutation strategies have been applied to unravel biosynthetic routes that sustain the inter- and intra-species cell wall diversity within LAB. Interplay with global cell metabolism has been deciphered that improved our fundamental understanding of the plasticity of the cell wall during growth. The cell wall is also decisive for the antimicrobial activity of many bacteriocins, for bacteriophage infection and for the interactions with the external environment. Therefore, genetic circuits involved in monitoring cell wall damage have been described in LAB, together with a plethora of defence mechanisms that help them to cope with external threats and adapt to harsh conditions. Since the cell wall plays a pivotal role in several technological and health-promoting traits of LAB, we anticipate that this knowledge will pave the way for the future development and extended applications of LAB.
Collapse
Affiliation(s)
- Beatriz Martínez
- DairySafe research group. Department of Technology and Biotechnology of Dairy Products. Instituto de Productos Lácteos de Asturias, IPLA-CSIC. Paseo Río Linares s/n. 33300 Villaviciosa, Spain
| | - Ana Rodríguez
- DairySafe research group. Department of Technology and Biotechnology of Dairy Products. Instituto de Productos Lácteos de Asturias, IPLA-CSIC. Paseo Río Linares s/n. 33300 Villaviciosa, Spain
| | - Saulius Kulakauskas
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
| | | |
Collapse
|
35
|
Liu ZX, Huang SL, Hou J, Guo XP, Wang FS, Sheng JZ. Cell-based high-throughput screening of polysaccharide biosynthesis hosts. Microb Cell Fact 2021; 20:62. [PMID: 33663495 PMCID: PMC7934428 DOI: 10.1186/s12934-021-01555-w] [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: 06/23/2020] [Accepted: 02/26/2021] [Indexed: 02/05/2023] Open
Abstract
Valuable polysaccharides are usually produced using wild-type or metabolically-engineered host microbial strains through fermentation. These hosts act as cell factories that convert carbohydrates, such as monosaccharides or starch, into bioactive polysaccharides. It is desirable to develop effective in vivo high-throughput approaches to screen cells that display high-level synthesis of the desired polysaccharides. Uses of single or dual fluorophore labeling, fluorescence quenching, or biosensors are effective strategies for cell sorting of a library that can be applied during the domestication of industrial engineered strains and metabolic pathway optimization of polysaccharide synthesis in engineered cells. Meanwhile, high-throughput screening strategies using each individual whole cell as a sorting section are playing growing roles in the discovery and directed evolution of enzymes involved in polysaccharide biosynthesis, such as glycosyltransferases. These enzymes and their mutants are in high demand as tool catalysts for synthesis of saccharides in vitro and in vivo. This review provides an introduction to the methodologies of using cell-based high-throughput screening for desired polysaccharide-biosynthesizing cells, followed by a brief discussion of potential applications of these approaches in glycoengineering.
Collapse
Affiliation(s)
- Zi-Xu Liu
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China
| | - Si-Ling Huang
- Bloomage BioTechnology Corp., Ltd., Jinan, 250010, China
| | - Jin Hou
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, China
| | - Xue-Ping Guo
- Bloomage BioTechnology Corp., Ltd., Jinan, 250010, China
| | - Feng-Shan Wang
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China. .,National Glycoengineering Research Center, Shandong University, Jinan, 250012, China.
| | - Ju-Zheng Sheng
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China. .,National Glycoengineering Research Center, Shandong University, Jinan, 250012, China.
| |
Collapse
|
36
|
Hernández-Rocamora VM, Baranova N, Peters K, Breukink E, Loose M, Vollmer W. Real-time monitoring of peptidoglycan synthesis by membrane-reconstituted penicillin-binding proteins. eLife 2021; 10:61525. [PMID: 33625355 PMCID: PMC7943195 DOI: 10.7554/elife.61525] [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: 07/28/2020] [Accepted: 02/23/2021] [Indexed: 11/13/2022] Open
Abstract
Peptidoglycan is an essential component of the bacterial cell envelope that surrounds the cytoplasmic membrane to protect the cell from osmotic lysis. Important antibiotics such as β-lactams and glycopeptides target peptidoglycan biosynthesis. Class A penicillin-binding proteins (PBPs) are bifunctional membrane-bound peptidoglycan synthases that polymerize glycan chains and connect adjacent stem peptides by transpeptidation. How these enzymes work in their physiological membrane environment is poorly understood. Here, we developed a novel Förster resonance energy transfer-based assay to follow in real time both reactions of class A PBPs reconstituted in liposomes or supported lipid bilayers and applied this assay with PBP1B homologues from Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii in the presence or absence of their cognate lipoprotein activator. Our assay will allow unravelling the mechanisms of peptidoglycan synthesis in a lipid-bilayer environment and can be further developed to be used for high-throughput screening for new antimicrobials.
Collapse
Affiliation(s)
- Víctor M Hernández-Rocamora
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Natalia Baranova
- Institute for Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | - Katharina Peters
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Eefjan Breukink
- Membrane Biochemistry and Biophysics, Bijvoet Centre for Biomolecular Research, University of Utrecht, Utrecht, Netherlands
| | - Martin Loose
- Institute for Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| |
Collapse
|
37
|
Szczepaniak J, Press C, Kleanthous C. The multifarious roles of Tol-Pal in Gram-negative bacteria. FEMS Microbiol Rev 2021; 44:490-506. [PMID: 32472934 PMCID: PMC7391070 DOI: 10.1093/femsre/fuaa018] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 05/28/2020] [Indexed: 12/15/2022] Open
Abstract
In the 1960s several groups reported the isolation and preliminary genetic mapping of
Escherichia coli strains tolerant towards the
action of colicins. These pioneering studies kick-started two new fields in bacteriology;
one centred on how bacteriocins like colicins exploit the Tol (or more commonly Tol-Pal)
system to kill bacteria, the other on the physiological role of this cell
envelope-spanning assembly. The following half century has seen significant advances in
the first of these fields whereas the second has remained elusive, until recently. Here,
we review work that begins to shed light on Tol-Pal function in Gram-negative bacteria.
What emerges from these studies is that Tol-Pal is an energised system with fundamental,
interlinked roles in cell division – coordinating the re-structuring of peptidoglycan at
division sites and stabilising the connection between the outer membrane and underlying
cell wall. This latter role is achieved by Tol-Pal exploiting the proton motive force to
catalyse the accumulation of the outer membrane peptidoglycan associated lipoprotein Pal
at division sites while simultaneously mobilising Pal molecules from around the cell.
These studies begin to explain the diverse phenotypic outcomes of tol-pal
mutations, point to other cell envelope roles Tol-Pal may have and raise many new
questions.
Collapse
Affiliation(s)
- Joanna Szczepaniak
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford OX1 3QU, UK
| | - Cara Press
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford OX1 3QU, UK
| | - Colin Kleanthous
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford OX1 3QU, UK
| |
Collapse
|
38
|
Ducret A, Grangeasse C. Recent progress in our understanding of peptidoglycan assembly in Firmicutes. Curr Opin Microbiol 2021; 60:44-50. [PMID: 33588129 DOI: 10.1016/j.mib.2021.01.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 01/13/2021] [Accepted: 01/27/2021] [Indexed: 02/06/2023]
Abstract
Years of intense research have shown that the assembly of peptidoglycan, the extracellular mesh-like polymer surrounding the bacterial cell, is incredibly complex. It requires a suite of reactions catalyzed by dynamic macromolecular protein complexes whose localization and activity should be finely regulated in space and time. In this review, we focus on the main developments reported over the last five years for the assembly of peptidoglycan in Firmicutes, a bacterial phylum that comprises monoderm bacteria and that encompasses well studied bacterial models with different cell shapes and lifestyles.
Collapse
Affiliation(s)
- Adrien Ducret
- Molecular Microbiology and Structural Biochemistry, CNRS UMR 5086, Université de Lyon, 7 passage du Vercors, 69367 Lyon, France
| | - Christophe Grangeasse
- Molecular Microbiology and Structural Biochemistry, CNRS UMR 5086, Université de Lyon, 7 passage du Vercors, 69367 Lyon, France.
| |
Collapse
|
39
|
Yin J, Zhang T, Cai J, Lou J, Cheng D, Zhou W, Xu C, Liu Y, Gao H, Yu Z. PBP1a glycosyltransferase and transpeptidase activities are both required for maintaining cell morphology and envelope integrity in Shewanella oneidensis. FEMS Microbiol Lett 2021; 367:5731804. [PMID: 32037461 DOI: 10.1093/femsle/fnaa026] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 02/07/2020] [Indexed: 12/29/2022] Open
Abstract
In rod-shaped Gram-negative bacteria, penicillin binding protein 1a (PBP1a) and 1b (PBP1b) form peptidoglycan-synthesizing complexes with the outer membrane lipoprotein LpoA and LpoB, respectively. Escherichia coli mutants lacking PBP1b/LpoB are sicker than those lacking PBP1a/LpoA. However, we previously found that mutants lacking PBP1a/LpoA but not PBP1b/LpoB are deleterious in Shewanella oneidensis. Here, we show that S. oneidensis PBP1a (SoPBP1a) contains conserved signature motifs with its E. coli counterpart, EcPBP1a. Although EcPBP1a play a less prominent role in E. coli, it is capable of substituting for the SoPBP1a in a manner dependent on SoLpoA. In S. oneidensis, expression of PBP1b is lower than PBP1a, and therefore the additional expression of SoPBP1b at low levels can functionally compensate for the absence of SoPBP1a. Importantly, S. oneidensis PBP1a variants lacking either glycosyltransferase (GTase) or transpeptidase (TPase) activity fail to maintain normal morphology and cell envelope integrity. Similarly, SoPBP1b variants also fail to compensate for the loss of SoPBP1a. Furthermore, overproduction of variants of SoPBP1a, but not SoPBP1b, has detrimental effects on cell morphology in S. oneidensis wild type cells. Overall, our results indicate that the combined enzymatic activities of SoPBP1a are essential for cell wall homeostasis.
Collapse
Affiliation(s)
- Jianhua Yin
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, Zhejiang Province, China
| | - Ting Zhang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, Zhejiang Province, China
| | - Jingxiao Cai
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, Zhejiang Province, China
| | - Jie Lou
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, Zhejiang Province, China
| | - Dan Cheng
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, Zhejiang Province, China
| | - Weifeng Zhou
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, Zhejiang Province, China
| | - Chaoyi Xu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, Zhejiang Province, China
| | - Yanqiu Liu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, Zhejiang Province, China
| | - Haichun Gao
- College of Life sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, Zhejiang Province, China
| | - Zhiliang Yu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, Zhejiang Province, China
| |
Collapse
|
40
|
Geerlings NMJ, Geelhoed JS, Vasquez-Cardenas D, Kienhuis MVM, Hidalgo-Martinez S, Boschker HTS, Middelburg JJ, Meysman FJR, Polerecky L. Cell Cycle, Filament Growth and Synchronized Cell Division in Multicellular Cable Bacteria. Front Microbiol 2021; 12:620807. [PMID: 33584623 PMCID: PMC7873302 DOI: 10.3389/fmicb.2021.620807] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 01/06/2021] [Indexed: 11/13/2022] Open
Abstract
Cable bacteria are multicellular, Gram-negative filamentous bacteria that display a unique division of metabolic labor between cells. Cells in deeper sediment layers are oxidizing sulfide, while cells in the surface layers of the sediment are reducing oxygen. The electrical coupling of these two redox half reactions is ensured via long-distance electron transport through a network of conductive fibers that run in the shared cell envelope of the centimeter-long filament. Here we investigate how this unique electrogenic metabolism is linked to filament growth and cell division. Combining dual-label stable isotope probing (13C and 15N), nanoscale secondary ion mass spectrometry, fluorescence microscopy and genome analysis, we find that the cell cycle of cable bacteria cells is highly comparable to that of other, single-celled Gram-negative bacteria. However, the timing of cell growth and division appears to be tightly and uniquely controlled by long-distance electron transport, as cell division within an individual filament shows a remarkable synchronicity that extends over a millimeter length scale. To explain this, we propose the "oxygen pacemaker" model in which a filament only grows when performing long-distance transport, and the latter is only possible when a filament has access to oxygen so it can discharge electrons from its internal electrical network.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Filip J. R. Meysman
- Department of Biology, University of Antwerp, Antwerp, Belgium
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
| | - Lubos Polerecky
- Department of Earth Sciences, Utrecht University, Utrecht, Netherlands
| |
Collapse
|
41
|
Stable inheritance of Sinorhizobium meliloti cell growth polarity requires an FtsN-like protein and an amidase. Nat Commun 2021; 12:545. [PMID: 33483499 PMCID: PMC7822825 DOI: 10.1038/s41467-020-20739-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 12/17/2020] [Indexed: 12/12/2022] Open
Abstract
In Rhizobiales bacteria, such as Sinorhizobium meliloti, cell elongation takes place only at new cell poles, generated by cell division. Here, we show that the role of the FtsN-like protein RgsS in S. meliloti extends beyond cell division. RgsS contains a conserved SPOR domain known to bind amidase-processed peptidoglycan. This part of RgsS and peptidoglycan amidase AmiC are crucial for reliable selection of the new cell pole as cell elongation zone. Absence of these components increases mobility of RgsS molecules, as well as abnormal RgsS accumulation and positioning of the growth zone at the old cell pole in about one third of the cells. These cells with inverted growth polarity are able to complete the cell cycle but show partially impaired chromosome segregation. We propose that amidase-processed peptidoglycan provides a landmark for RgsS to generate cell polarity in unipolarly growing Rhizobiales. In Sinorhizobium bacteria, cell elongation takes place only at new cell poles, generated by cell division. Here, Krol et al. show that an FtsN-like protein and a peptidoglycan amidase are crucial for reliable selection of the new cell pole as cell elongation zone.
Collapse
|
42
|
Iwata Y, Sakai N, Yoneda I, Senda Y, Sakai-Takemori Y, Oshima M, Nakagawa-Yoneda S, Ogura H, Sato K, Minami T, Kitajima S, Toyama T, Yamamura Y, Miyagawa T, Hara A, Shimizu M, Furuichi K, Matsushima K, Wada T. D-Serine inhibits the attachment and biofilm formation of methicillin-resistant Staphylococcus aureus. Biochem Biophys Res Commun 2021; 537:50-56. [PMID: 33385805 DOI: 10.1016/j.bbrc.2020.12.078] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 12/22/2020] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Although therapeutic agents for methicillin-resistant Staphylococcus aureus (MRSA) are clinically available, MRSA infection is still a life-threatening disease. Bacterial attachment and biofilm formation contribute significantly to the initiation of MRSA infection. Controlling MRSA's attachment and biofilm formation might reduce the frequency of MRSA infection. According to recent data, some amino acids can reduce MRSA's attachment on plates; however, their precise inhibitory mechanisms remain unclear. Therefore, we explored the effect of the amino acids on bacterial adhesion and biofilm formation in vitro and in vivo MRSA infection models. METHODS We tested the inhibitory effect of amino acids on MRSA and Escherichia coli (E. coli) in the attachment assay. Moreover, we evaluated the therapeutic potential of amino acids on the in vivo catheter infection model. RESULTS Among the amino acids, D-Serine (D-Ser) was found to reduce MRSA's ability to attach on plate assay. The proliferation of MRSA was not affected by the addition of D-Ser; thus, D-Ser likely only played a role in preventing attachment and biofilm formation. Then, we analyzed the expression of genes related to attachment and biofilm formation. D-Ser was found to reduce the expressions of AgrA, SarS, IcaA, DltD, and SdrD. Moreover, the polyvinyl chloride catheters treated with D-Ser had fewer MRSA colonies. D-Ser treatment also reduced the severity of infection in the catheter-induced peritonitis model. Moreover, D-Ser reduced the attachment ability of E. coli. CONCLUSION D-Ser inhibits the attachment and biofilm formation of MRSA by reducing the expression of the related genes. Also, the administration of D-Ser reduces the severity of catheter infection in the mouse model. Therefore, D-Ser may be a promising therapeutic option for MRSA as well as E. coli infection.
Collapse
Affiliation(s)
- Yasunori Iwata
- Division of Infection Control, Japan; Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan.
| | - Norihiko Sakai
- Division of Blood Purification, Kanazawa University Hospital, Japan; Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Ikuko Yoneda
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | | | | | - Megumi Oshima
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | | | - Hisayuki Ogura
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Koichi Sato
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Taichiro Minami
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Shinji Kitajima
- Division of Blood Purification, Kanazawa University Hospital, Japan; Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Tadashi Toyama
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Yuta Yamamura
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Taro Miyagawa
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Akinori Hara
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Miho Shimizu
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| | - Kengo Furuichi
- Division of Nephrology, Kanazawa Medical University School of Medicine, Ishikawa, Japan
| | - Kouji Matsushima
- Department of Molecular Preventive Medicine, University of Tokyo, Tokyo, Japan; Division of Molecular Regulation of Inflammatory and Immune Diseases, Research Institute of Biomedical Sciences, Tokyo University of Science, Chiba, Japan
| | - Takashi Wada
- Department of Nephrology and Laboratory Medicine, Kanazawa University, Japan
| |
Collapse
|
43
|
Brown NW, Shirley JD, Marshall AP, Carlson EE. Comparison of Bioorthogonal β-Lactone Activity-Based Probes for Selective Labeling of Penicillin-Binding Proteins. Chembiochem 2021; 22:193-202. [PMID: 32964667 PMCID: PMC7790944 DOI: 10.1002/cbic.202000556] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/21/2020] [Indexed: 01/20/2023]
Abstract
Penicillin-binding proteins (PBPs) are a family of bacterial enzymes that are key components of cell-wall biosynthesis and the target of β-lactam antibiotics. Most microbial pathogens contain multiple structurally homologous PBP isoforms, making it difficult to target individual PBPs. To study the roles and regulation of specific PBP isoforms, a panel of bioorthogonal β-lactone probes was synthesized and compared. Fluorescent labeling confirmed selectivity, and PBPs were selectively enriched from Streptococcus pneumoniae lysates. Comparisons between fluorescent labeling of probes revealed that the accessibility of bioorthogonal reporter molecules to the bound probe in the native protein environment exerts a more significant effect on labeling intensity than the bioorthogonal reaction used, observations that are likely applicable beyond this class of probes or proteins. Selective, bioorthogonal activity-based probes for PBPs will facilitate the activity-based determination of the roles and regulation of specific PBP isoforms, a key gap in knowledge that has yet to be filled.
Collapse
Affiliation(s)
- Nathaniel W Brown
- Department of Chemistry, University of Minnesota-Twin Cities 139 Smith Hall, Pleasant Street SE, Minneapolis, MN, 55455, USA
| | - Joshua D Shirley
- Department of Medicinal Chemistry, University of Minnesota-Twin Cities, 308 Harvard Street SE, Minneapolis, MN, 55455, USA
| | - Andrew P Marshall
- Department of Chemistry, University of Minnesota-Twin Cities 139 Smith Hall, Pleasant Street SE, Minneapolis, MN, 55455, USA
| | - Erin E Carlson
- Department of Chemistry, University of Minnesota-Twin Cities 139 Smith Hall, Pleasant Street SE, Minneapolis, MN, 55455, USA
- Department of Medicinal Chemistry, University of Minnesota-Twin Cities, 308 Harvard Street SE, Minneapolis, MN, 55455, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota-Twin Cities, 321 Church Street SE, Minneapolis, MN, 55455, USA
| |
Collapse
|
44
|
A dynamic, ring-forming MucB / RseB-like protein influences spore shape in Bacillus subtilis. PLoS Genet 2020; 16:e1009246. [PMID: 33315869 PMCID: PMC7769602 DOI: 10.1371/journal.pgen.1009246] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 12/28/2020] [Accepted: 11/03/2020] [Indexed: 01/17/2023] Open
Abstract
How organisms develop into specific shapes is a central question in biology. The maintenance of bacterial shape is connected to the assembly and remodelling of the cell envelope. In endospore-forming bacteria, the pre-spore compartment (the forespore) undergoes morphological changes that result in a spore of defined shape, with a complex, multi-layered cell envelope. However, the mechanisms that govern spore shape remain poorly understood. Here, using a combination of fluorescence microscopy, quantitative image analysis, molecular genetics and transmission electron microscopy, we show that SsdC (formerly YdcC), a poorly-characterized new member of the MucB / RseB family of proteins that bind lipopolysaccharide in diderm bacteria, influences spore shape in the monoderm Bacillus subtilis. Sporulating cells lacking SsdC fail to adopt the typical oblong shape of wild-type forespores and are instead rounder. 2D and 3D-fluorescence microscopy suggest that SsdC forms a discontinuous, dynamic ring-like structure in the peripheral membrane of the mother cell, near the mother cell proximal pole of the forespore. A synthetic sporulation screen identified genetic relationships between ssdC and genes involved in the assembly of the spore coat. Phenotypic characterization of these mutants revealed that spore shape, and SsdC localization, depend on the coat basement layer proteins SpoVM and SpoIVA, the encasement protein SpoVID and the inner coat protein SafA. Importantly, we found that the ΔssdC mutant produces spores with an abnormal-looking cortex, and abolishing cortex synthesis in the mutant largely suppresses its shape defects. Thus, SsdC appears to play a role in the proper assembly of the spore cortex, through connections to the spore coat. Collectively, our data suggest functional diversification of the MucB / RseB protein domain between diderm and monoderm bacteria and identify SsdC as an important factor in spore shape development. Cell shape is an important cellular attribute linked to cellular function and environmental adaptation. Bacterial endospores are one of the toughest cell types on Earth, with a defined shape and complex, highly-resistant, multi-layered cell envelope. Although decades of research have focused on defining the composition and assembly of the multi-layered spore envelope, little is known about how these layers contribute to spore shape. Here, we identify SsdC, a poorly-characterized new member of the MucB / RseB family of proteins that bind lipopolysaccharide in diderm bacteria. We show that SsdC is an important factor in spore shape development in the monoderm, model organism Bacillus subtilis. Our data suggest that SsdC influences the assembly of the spore cortex, through connections to the spore coat, by forming an intriguing, dynamic ring-like structure adjacent to the developing spore. Furthermore, our identification of SsdC suggests evolutionary diversification of the MucB /RseB protein domain between diderm and monoderm bacteria.
Collapse
|
45
|
Qiao W, Qiao Y, Liu F, Zhang Y, Li R, Wu Z, Xu H, Saris PEJ, Qiao M. Engineering Lactococcus lactis as a multi-stress tolerant biosynthetic chassis by deleting the prophage-related fragment. Microb Cell Fact 2020; 19:225. [PMID: 33298073 PMCID: PMC7727215 DOI: 10.1186/s12934-020-01487-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/28/2020] [Indexed: 01/02/2023] Open
Abstract
Background In bioengineering, growth of microorganisms is limited because of environmental and industrial stresses during fermentation. This study aimed to construct a nisin-producing chassis Lactococcus lactis strain with genome-streamlined, low metabolic burden, and multi-stress tolerance characteristics. Results The Cre-loxP recombination system was applied to reduce the genome and obtain the target chassis strain. A prophage-related fragment (PRF; 19,739 bp) in the L. lactis N8 genome was deleted, and the mutant strain L. lactis N8-1 was chosen for multi-stress tolerance studies. Nisin immunity of L. lactis N8-1 was increased to 6500 IU/mL, which was 44.44% higher than that of the wild-type L. lactis N8 (4500 IU/mL). The survival rates of L. lactis N8-1 treated with lysozyme for 2 h and lactic acid for 1 h were 1000- and 10,000-fold higher than that of the wild-type strain, respectively. At 39 ℃, the L. lactis N8-1 could still maintain its growth, whereas the growth of the wild-type strain dramatically dropped. Scanning electron microscopy showed that the cell wall integrity of L. lactis N8-1 was well maintained after lysozyme treatment. Tandem mass tags labeled quantitative proteomics revealed that 33 and 9 proteins were significantly upregulated and downregulated, respectively, in L. lactis N8-1. These differential proteins were involved in carbohydrate and energy transport/metabolism, biosynthesis of cell wall and cell surface proteins. Conclusions PRF deletion was proven to be an efficient strategy to achieve multi-stress tolerance and nisin immunity in L. lactis, thereby providing a new perspective for industrially obtaining engineered strains with multi-stress tolerance and expanding the application of lactic acid bacteria in biotechnology and synthetic biology. Besides, the importance of PRF, which can confer vital phenotypes to bacteria, was established.
Collapse
Affiliation(s)
- Wanjin Qiao
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, No.94 Weijin Road, Nankai District, Tianjin, 300071, China.,Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Yu Qiao
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, No.94 Weijin Road, Nankai District, Tianjin, 300071, China
| | - Fulu Liu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, No.94 Weijin Road, Nankai District, Tianjin, 300071, China
| | - Yating Zhang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, No.94 Weijin Road, Nankai District, Tianjin, 300071, China
| | - Ran Li
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Zhenzhou Wu
- State Key Laboratory of Medicinal Chemical Biology & Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin, China
| | - Haijin Xu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, No.94 Weijin Road, Nankai District, Tianjin, 300071, China.
| | - Per Erik Joakim Saris
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Mingqiang Qiao
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, No.94 Weijin Road, Nankai District, Tianjin, 300071, China.
| |
Collapse
|
46
|
García-Del Portillo F. Building peptidoglycan inside eukaryotic cells: A view from symbiotic and pathogenic bacteria. Mol Microbiol 2020; 113:613-626. [PMID: 32185832 PMCID: PMC7154730 DOI: 10.1111/mmi.14452] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/08/2019] [Accepted: 01/09/2020] [Indexed: 12/13/2022]
Abstract
The peptidoglycan (PG), as the exoskeleton of most prokaryotes, maintains a defined shape and ensures cell integrity against the high internal turgor pressure. These important roles have attracted researchers to target PG metabolism in order to control bacterial infections. Most studies, however, have been performed in bacteria grown under laboratory conditions, leading to only a partial view on how the PG is synthetized in natural environments. As a case in point, PG metabolism and its regulation remain poorly understood in symbiotic and pathogenic bacteria living inside eukaryotic cells. This review focuses on the PG metabolism of intracellular bacteria, emphasizing the necessity of more in vivo studies involving the analysis of enzymes produced in the intracellular niche and the isolation of PG from bacteria residing within eukaryotic cells. The review also points to persistent infections caused by some intracellular bacterial pathogens and the extent at which the PG could contribute to establish such physiological state. Based on recent evidences, I speculate on the idea that certain structural features of the PG may facilitate attenuation of intracellular growth. Lastly, I discuss recent findings in endosymbionts supporting a cooperation between host and bacterial enzymes to assemble a mature PG.
Collapse
|
47
|
Wood TE, Howard SA, Förster A, Nolan LM, Manoli E, Bullen NP, Yau HCL, Hachani A, Hayward RD, Whitney JC, Vollmer W, Freemont PS, Filloux A. The Pseudomonas aeruginosa T6SS Delivers a Periplasmic Toxin that Disrupts Bacterial Cell Morphology. Cell Rep 2020; 29:187-201.e7. [PMID: 31577948 PMCID: PMC6899460 DOI: 10.1016/j.celrep.2019.08.094] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 07/02/2019] [Accepted: 08/27/2019] [Indexed: 01/10/2023] Open
Abstract
The type VI secretion system (T6SS) is crucial in interbacterial competition and is a virulence determinant of many Gram-negative bacteria. Several T6SS effectors are covalently fused to secreted T6SS structural components such as the VgrG spike for delivery into target cells. In Pseudomonas aeruginosa, the VgrG2b effector was previously proposed to mediate bacterial internalization into eukaryotic cells. In this work, we find that the VgrG2b C-terminal domain (VgrG2bC-ter) elicits toxicity in the bacterial periplasm, counteracted by a cognate immunity protein. We resolve the structure of VgrG2bC-ter and confirm it is a member of the zinc-metallopeptidase family of enzymes. We show that this effector causes membrane blebbing at midcell, which suggests a distinct type of T6SS-mediated growth inhibition through interference with cell division, mimicking the impact of β-lactam antibiotics. Our study introduces a further effector family to the T6SS arsenal and demonstrates that VgrG2b can target both prokaryotic and eukaryotic cells. The structure of the VgrG2b C-terminal domain presents a metallopeptidase fold VgrG2b exerts antibacterial activity in the periplasmic space Toxicity of VgrG2b is counteracted by a cognate periplasmic immunity protein VgrG2bC-ter-intoxicated prey cells bleb at the midcell and lyse
Collapse
Affiliation(s)
- Thomas E Wood
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Sophie A Howard
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Andreas Förster
- Section of Structural Biology, Department of Medicine, Imperial College London, London SW7 2AZ, UK
| | - Laura M Nolan
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Eleni Manoli
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Nathan P Bullen
- Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON L8S 4K1, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Hamish C L Yau
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Abderrahman Hachani
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Richard D Hayward
- Division of Microbiology and Parasitology, Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK
| | - John C Whitney
- Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON L8S 4K1, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Paul S Freemont
- Section of Structural Biology, Department of Medicine, Imperial College London, London SW7 2AZ, UK
| | - Alain Filloux
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
| |
Collapse
|
48
|
Lin L, Wu Q, Song J, Du Y, Gao J, Song Y, Wang W, Yang C. Revealing the in vivo growth and division patterns of mouse gut bacteria. SCIENCE ADVANCES 2020; 6:6/36/eabb2531. [PMID: 32917613 PMCID: PMC7473744 DOI: 10.1126/sciadv.abb2531] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 07/13/2020] [Indexed: 06/11/2023]
Abstract
Current techniques for studying gut microbiota are unable to answer some important microbiology questions, like how different bacteria grow and divide in the gut. We propose a method that integrates the use of sequential d-amino acid-based in vivo metabolic labeling with fluorescence in situ hybridization (FISH), for characterizing the growth and division patterns of gut bacteria. After sequentially administering two d-amino acid-based probes containing different fluorophores to mice by gavage, the resulting dual-labeled peptidoglycans provide temporal information on cell wall synthesis of gut bacteria. Following taxonomic identification with FISH probes, the growth and division patterns of the corresponding bacterial taxa, including species that cannot be cultured separately in vitro, are revealed. Our method offers a facile yet powerful tool for investigating the in vivo growth dynamics of the bacterial gut microbiota, which will advance our understanding of bacterial cytology and facilitate elucidation of the basic microbiology of this gut "dark matter."
Collapse
Affiliation(s)
- Liyuan Lin
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China
| | - Qiuyue Wu
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China
- The MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, Key Laboratory for Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jia Song
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China
| | - Yahui Du
- The MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, Key Laboratory for Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Juan Gao
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China
| | - Yanling Song
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China
- The MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, Key Laboratory for Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Wei Wang
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
| | - Chaoyong Yang
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
- The MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, Key Laboratory for Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| |
Collapse
|
49
|
Wu LJ, Lee S, Park S, Eland LE, Wipat A, Holden S, Errington J. Geometric principles underlying the proliferation of a model cell system. Nat Commun 2020; 11:4149. [PMID: 32811832 PMCID: PMC7434903 DOI: 10.1038/s41467-020-17988-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 07/24/2020] [Indexed: 02/07/2023] Open
Abstract
Many bacteria can form wall-deficient variants, or L-forms, that divide by a simple mechanism that does not require the FtsZ-based cell division machinery. Here, we use microfluidic systems to probe the growth, chromosome cycle and division mechanism of Bacillus subtilis L-forms. We find that forcing cells into a narrow linear configuration greatly improves the efficiency of cell growth and chromosome segregation. This reinforces the view that L-form division is driven by an excess accumulation of surface area over volume. Cell geometry also plays a dominant role in controlling the relative positions and movement of segregating chromosomes. Furthermore, the presence of the nucleoid appears to influence division both via a cell volume effect and by nucleoid occlusion, even in the absence of FtsZ. Our results emphasise the importance of geometric effects for a range of crucial cell functions, and are of relevance for efforts to develop artificial or minimal cell systems.
Collapse
Affiliation(s)
- Ling Juan Wu
- Centre for Bacterial Cell Biology, Biosciences Institute, Medical School, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK.
| | - Seoungjun Lee
- grid.1006.70000 0001 0462 7212Centre for Bacterial Cell Biology, Biosciences Institute, Medical School, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX UK ,grid.13097.3c0000 0001 2322 6764Present Address: Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, SE5 9RX UK
| | - Sungshic Park
- grid.1006.70000 0001 0462 7212Centre for Bacterial Cell Biology, Biosciences Institute, Medical School, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX UK ,grid.1006.70000 0001 0462 7212Interdisciplinary Computing and Complex BioSystems research group, School of Computing, Newcastle University, Newcastle upon Tyne, NE4 5TG UK
| | - Lucy E. Eland
- grid.1006.70000 0001 0462 7212Centre for Bacterial Cell Biology, Biosciences Institute, Medical School, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX UK ,grid.1006.70000 0001 0462 7212Interdisciplinary Computing and Complex BioSystems research group, School of Computing, Newcastle University, Newcastle upon Tyne, NE4 5TG UK
| | - Anil Wipat
- grid.1006.70000 0001 0462 7212Centre for Bacterial Cell Biology, Biosciences Institute, Medical School, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX UK ,grid.1006.70000 0001 0462 7212Interdisciplinary Computing and Complex BioSystems research group, School of Computing, Newcastle University, Newcastle upon Tyne, NE4 5TG UK
| | - Séamus Holden
- grid.1006.70000 0001 0462 7212Centre for Bacterial Cell Biology, Biosciences Institute, Medical School, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX UK
| | - Jeff Errington
- Centre for Bacterial Cell Biology, Biosciences Institute, Medical School, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK.
| |
Collapse
|
50
|
Ramachandran B, Jeyakanthan J, Lopes BS. Molecular docking, dynamics and free energy analyses of Acinetobacter baumannii OXA class enzymes with carbapenems investigating their hydrolytic mechanisms. J Med Microbiol 2020; 69:1062-1078. [PMID: 32773005 DOI: 10.1099/jmm.0.001233] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Introduction. Acinetobacter baumannii is a critical priority pathogen listed by the World Health Organization due to increasing levels of resistance to carbapenem classes of antibiotics. It causes wound and other nosocomial infections, which can be life-threatening. Hence, there is an urgent need for the development of new classes of antibiotics.Aim. To study the interaction of carabapenems with class D beta-lactamases (oxacillinases) and analyse drug resistance by studying enzyme-substrate complexes using modelling approaches as a means of establishing correlations with the phenotypic data.Methodology. The three-dimensional structures of carbapenems (doripenem, ertapenem, imipenem and meropenem) were obtained from DrugBank and screened against class D beta-lactamases. Further, the study was extended with their variants. The variants' structure was homology-modelled using the Schrödinger Prime module (Schrödinger LLC, NY, USA).Results. The first discovered intrinsic beta-lactamase of Acinetobacter baumannii, OXA-51, had a binding energy value of -40.984 kcal mol-1, whereas other OXA-51 variants, such as OXA-64, OXA-110 and OXA-111, have values of -60.638, -66.756 and -67.751 kcal mol-1, respectively. The free energy values of OXA-51 variants produced better results than those of other groups.Conclusions. Imipenem and meropenem showed MIC values of 2 and 8 µg ml-1, respectively against OXA-51 in earlier studies, indicating that these are the most effective drugs for treatment of A. baumannii infection. According to our results, OXA-51 is an active enzyme that shows better interactions and is capable of hydrolyzing carbapenems. When correlating the hydrogen-bonding interaction with MIC values, the predicted results are in good agreement and might provide initial insights into performing similar studies related to OXA variants or other antibiotic-enzyme-based studies.
Collapse
Affiliation(s)
- Balajee Ramachandran
- Structural Biology and Bio-computing Lab, Department of Bioinformatics, Alagappa University, Karaikudi - 630 004, Tamil Nadu, India
| | - Jeyaraman Jeyakanthan
- Structural Biology and Bio-computing Lab, Department of Bioinformatics, Alagappa University, Karaikudi - 630 004, Tamil Nadu, India
| | - Bruno S Lopes
- School of Medicine, Medical Sciences and Nutrition, 0:025 Polwarth building, Foresterhill, Aberdeen AB25 2ZD, UK
| |
Collapse
|