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Son Y, Kim B, Kim P, Min J, Park Y, Yang J, Kim W, Toyofuku M, Park W. Unexpected vulnerability of Enterococcus faecium to polymyxin B under anaerobic condition. Gut Microbes 2024; 16:2438465. [PMID: 39663231 DOI: 10.1080/19490976.2024.2438465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 10/14/2024] [Accepted: 11/26/2024] [Indexed: 12/13/2024] Open
Abstract
Gram-positive Enterococcus faecium exhibited higher susceptibility (>4-fold) to polymyxin B (PMB), the canonical antimicrobial peptide against Gram-negative bacteria, under anaerobic condition than aerobic condition. Anaerobically grown E. faecium exhibited high vulnerability to PMB, leading to alteration of cell surface and morphology, as observed based on their high dansyl-PMB affinity (>2.9-fold), a proportion (>8.5-fold) of propidium iodide-stained cells, and observation of scanning electron microscopy results. Interestingly, our transcriptomic and chemical analyses revealed that enterocin B, produced anaerobically, imposes a burden on the cellular envelope when cells are exposed to PMB. This scenario was also supported by PMB susceptibility tests and killing curves, which showed that ΔentB knockout mutant cells were more resistant to PMB (32 µg/mL) compared to wild-type cells (4 µg/mL) under anaerobic condition. Fluorescent D-amino acid and BOCILLIN™-fluorescent profiling of transpeptidase activities in ΔentB mutant cells under anaerobic condition revealed similar levels of activity to those observed in WT cells under aerobic condition. The high level of secreted bacteriocins in WT under anaerobic condition likely led to significant membrane depolarization and loosening of the peptidoglycan layer, making the cells more permeable to PMB. Overall, our findings suggest that anaerobically produced bacteriocins, in conjunction with PMB, contribute to the killing of E. faecium by destabilizing its cell envelope.
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Affiliation(s)
- Yongjun Son
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
- Institute of Life Science and Natural Resources, Korea University, Seoul, Republic of Korea
| | - Bitnara Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
| | - Pureun Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
| | - Jihyeon Min
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
| | - Yerim Park
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
| | - Jihye Yang
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
| | - Wonjae Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
- Institute of Life Science and Natural Resources, Korea University, Seoul, Republic of Korea
| | - Masanori Toyofuku
- Department of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Woojun Park
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
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2
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Galinier A, Delan-Forino C, Foulquier E, Lakhal H, Pompeo F. Recent Advances in Peptidoglycan Synthesis and Regulation in Bacteria. Biomolecules 2023; 13:biom13050720. [PMID: 37238589 DOI: 10.3390/biom13050720] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/17/2023] [Accepted: 04/21/2023] [Indexed: 05/28/2023] Open
Abstract
Bacteria must synthesize their cell wall and membrane during their cell cycle, with peptidoglycan being the primary component of the cell wall in most bacteria. Peptidoglycan is a three-dimensional polymer that enables bacteria to resist cytoplasmic osmotic pressure, maintain their cell shape and protect themselves from environmental threats. Numerous antibiotics that are currently used target enzymes involved in the synthesis of the cell wall, particularly peptidoglycan synthases. In this review, we highlight recent progress in our understanding of peptidoglycan synthesis, remodeling, repair, and regulation in two model bacteria: the Gram-negative Escherichia coli and the Gram-positive Bacillus subtilis. By summarizing the latest findings in this field, we hope to provide a comprehensive overview of peptidoglycan biology, which is critical for our understanding of bacterial adaptation and antibiotic resistance.
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Affiliation(s)
- Anne Galinier
- Laboratoire de Chimie Bactérienne, UMR 7283, Institut de Microbiologie de la Méditerranée, CNRS/Aix-Marseille Univ, 31 Chemin Joseph Aiguier, 13009 Marseille, France
| | - Clémentine Delan-Forino
- Laboratoire de Chimie Bactérienne, UMR 7283, Institut de Microbiologie de la Méditerranée, CNRS/Aix-Marseille Univ, 31 Chemin Joseph Aiguier, 13009 Marseille, France
| | - Elodie Foulquier
- Laboratoire de Chimie Bactérienne, UMR 7283, Institut de Microbiologie de la Méditerranée, CNRS/Aix-Marseille Univ, 31 Chemin Joseph Aiguier, 13009 Marseille, France
| | - Hakima Lakhal
- Laboratoire de Chimie Bactérienne, UMR 7283, Institut de Microbiologie de la Méditerranée, CNRS/Aix-Marseille Univ, 31 Chemin Joseph Aiguier, 13009 Marseille, France
| | - Frédérique Pompeo
- Laboratoire de Chimie Bactérienne, UMR 7283, Institut de Microbiologie de la Méditerranée, CNRS/Aix-Marseille Univ, 31 Chemin Joseph Aiguier, 13009 Marseille, France
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3
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Ignacio BJ, Bakkum T, Bonger KM, Martin NI, van Kasteren SI. Metabolic labeling probes for interrogation of the host-pathogen interaction. Org Biomol Chem 2021; 19:2856-2870. [PMID: 33725048 DOI: 10.1039/d0ob02517h] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Bacterial infections are still one of the leading causes of death worldwide; despite the near-ubiquitous availability of antibiotics. With antibiotic resistance on the rise, there is an urgent need for novel classes of antibiotic drugs. One particularly troublesome class of bacteria are those that have evolved highly efficacious mechanisms for surviving inside the host. These contribute to their virulence by immune evasion, and make them harder to treat with antibiotics due to their residence inside intracellular membrane-limited compartments. This has sparked the development of new chemical reporter molecules and bioorthogonal probes that can be metabolically incorporated into bacteria to provide insights into their activity status. In this review, we provide an overview of several classes of metabolic labeling probes capable of targeting either the peptidoglycan cell wall, the mycomembrane of mycobacteria and corynebacteria, or specific bacterial proteins. In addition, we highlight several important insights that have been made using these metabolic labeling probes.
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Affiliation(s)
- Bob J Ignacio
- Institute for Molecules and Materials, Radbout Universiteit, Nijmegen, Gelderland, Netherlands
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4
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Cantlay S, Sen BC, Flärdh K, McCormick JR. Influence of core divisome proteins on cell division in Streptomyces venezuelae ATCC 10712. MICROBIOLOGY-SGM 2021; 167. [PMID: 33400639 DOI: 10.1099/mic.0.001015] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The sporulating, filamentous soil bacterium Streptomyces venezuelae ATCC 10712 differentiates under submerged and surface growth conditions. In order to lay a solid foundation for the study of development-associated division for this organism, a congenic set of mutants was isolated, individually deleted for a gene encoding either a cytoplasmic (i.e. ftsZ) or core inner membrane (i.e. divIC, ftsL, ftsI, ftsQ, ftsW) component of the divisome. While ftsZ mutants are completely blocked for division, single mutants in the other core divisome genes resulted in partial, yet similar, blocks in sporulation septum formation. Double and triple mutants for core divisome membrane components displayed phenotypes that were similar to those of the single mutants, demonstrating that the phenotypes were not synergistic. Division in this organism is still partially functional without multiple core divisome proteins, suggesting that perhaps other unknown lineage-specific proteins perform redundant functions. In addition, by isolating an ftsZ2p mutant with an altered -10 region, the conserved developmentally controlled promoter was also shown to be required for sporulation-associated division. Finally, microscopic observation of FtsZ-YFP dynamics in the different mutant backgrounds led to the conclusion that the initial assembly of regular Z rings does not per se require the tested divisome membrane proteins, but the stability of Z rings is dependent on the divisome membrane components tested. The observation is consistent with the interpretation that Z ring instability likely results from and further contributes to the observed defects in sporulation septation in mutants lacking core divisome proteins.
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Affiliation(s)
- Stuart Cantlay
- Present address: Department of Biological Sciences, West Liberty University, West Liberty, WV 26074, USA
- Department of Biological Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | | | - Klas Flärdh
- Department of Biology, Lund University, 223 62 Lund, Sweden
| | - Joseph R McCormick
- Department of Biological Sciences, Duquesne University, Pittsburgh, PA 15282, USA
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5
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Cambré A, Aertsen A. Bacterial Vivisection: How Fluorescence-Based Imaging Techniques Shed a Light on the Inner Workings of Bacteria. Microbiol Mol Biol Rev 2020; 84:e00008-20. [PMID: 33115939 PMCID: PMC7599038 DOI: 10.1128/mmbr.00008-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The rise in fluorescence-based imaging techniques over the past 3 decades has improved the ability of researchers to scrutinize live cell biology at increased spatial and temporal resolution. In microbiology, these real-time vivisections structurally changed the view on the bacterial cell away from the "watery bag of enzymes" paradigm toward the perspective that these organisms are as complex as their eukaryotic counterparts. Capitalizing on the enormous potential of (time-lapse) fluorescence microscopy and the ever-extending pallet of corresponding probes, initial breakthroughs were made in unraveling the localization of proteins and monitoring real-time gene expression. However, later it became clear that the potential of this technique extends much further, paving the way for a focus-shift from observing single events within bacterial cells or populations to obtaining a more global picture at the intra- and intercellular level. In this review, we outline the current state of the art in fluorescence-based vivisection of bacteria and provide an overview of important case studies to exemplify how to use or combine different strategies to gain detailed information on the cell's physiology. The manuscript therefore consists of two separate (but interconnected) parts that can be read and consulted individually. The first part focuses on the fluorescent probe pallet and provides a perspective on modern methodologies for microscopy using these tools. The second section of the review takes the reader on a tour through the bacterial cell from cytoplasm to outer shell, describing strategies and methods to highlight architectural features and overall dynamics within cells.
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Affiliation(s)
- Alexander Cambré
- KU Leuven, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, Leuven, Belgium
| | - Abram Aertsen
- KU Leuven, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, Leuven, Belgium
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6
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Morales Angeles D, Macia-Valero A, Bohorquez LC, Scheffers DJ. The PASTA domains of Bacillus subtilis PBP2B strengthen the interaction of PBP2B with DivIB. MICROBIOLOGY (READING, ENGLAND) 2020; 166:826-836. [PMID: 32749956 PMCID: PMC7654742 DOI: 10.1099/mic.0.000957] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/13/2020] [Indexed: 12/15/2022]
Abstract
Bacterial cell division is mediated by a protein complex known as the divisome. Many protein-protein interactions in the divisome have been characterized. In this report, we analyse the role of the PASTA (Penicillin-binding protein And Serine Threonine kinase Associated) domains of Bacillus subtilis PBP2B. PBP2B itself is essential and cannot be deleted, but removing the PBP2B PASTA domains results in impaired cell division and a heat-sensitive phenotype. This resembles the deletion of divIB, a known interaction partner of PBP2B. Bacterial two-hybrid and co-immunoprecipitation analyses show that the interaction between PBP2B and DivIB is weakened when the PBP2B PASTA domains are removed. Combined, our results show that the PBP2B PASTA domains are required to strengthen the interaction between PBP2B and DivIB.
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Affiliation(s)
- Danae Morales Angeles
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
- Present address: Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, 1432 Ås, Norway
| | - Alicia Macia-Valero
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Laura C. Bohorquez
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
- Present address: BluSense Diagnostics ApS, Carrera 63 100-49, Bogota 111121, Colombia
| | - Dirk-Jan Scheffers
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
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7
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Zielińska A, Savietto A, de Sousa Borges A, Martinez D, Berbon M, Roelofsen JR, Hartman AM, de Boer R, Van der Klei IJ, Hirsch AKH, Habenstein B, Bramkamp M, Scheffers DJ. Flotillin-mediated membrane fluidity controls peptidoglycan synthesis and MreB movement. eLife 2020; 9:e57179. [PMID: 32662773 PMCID: PMC7360373 DOI: 10.7554/elife.57179] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 06/12/2020] [Indexed: 01/07/2023] Open
Abstract
The bacterial plasma membrane is an important cellular compartment. In recent years it has become obvious that protein complexes and lipids are not uniformly distributed within membranes. Current hypotheses suggest that flotillin proteins are required for the formation of complexes of membrane proteins including cell-wall synthetic proteins. We show here that bacterial flotillins are important factors for membrane fluidity homeostasis. Loss of flotillins leads to a decrease in membrane fluidity that in turn leads to alterations in MreB dynamics and, as a consequence, in peptidoglycan synthesis. These alterations are reverted when membrane fluidity is restored by a chemical fluidizer. In vitro, the addition of a flotillin increases membrane fluidity of liposomes. Our data support a model in which flotillins are required for direct control of membrane fluidity rather than for the formation of protein complexes via direct protein-protein interactions.
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Affiliation(s)
- Aleksandra Zielińska
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningenNetherlands
| | - Abigail Savietto
- Biozentrum, Ludwig-Maximilians-Universität MünchenMünchenGermany
- Institute for General Microbiology, Christian-Albrechts-UniversityKielGermany
| | - Anabela de Sousa Borges
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningenNetherlands
| | - Denis Martinez
- Institute of Chemistry & Biology of Membranes & Nanoobjects (UMR5248 CBMN), IECB, CNRS, Université Bordeaux, Institut Polytechnique BordeauxPessacFrance
| | - Melanie Berbon
- Institute of Chemistry & Biology of Membranes & Nanoobjects (UMR5248 CBMN), IECB, CNRS, Université Bordeaux, Institut Polytechnique BordeauxPessacFrance
| | - Joël R Roelofsen
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningenNetherlands
| | - Alwin M Hartman
- Department of Drug Design and Optimization (DDOP), Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI)SaarbrückenGermany
- Department of Pharmacy, Saarland UniversitySaarbrückenGermany
- Stratingh Institute for Chemistry, University of GroningenGroningenNetherlands
| | - Rinse de Boer
- Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningenNetherlands
| | - Ida J Van der Klei
- Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningenNetherlands
| | - Anna KH Hirsch
- Department of Drug Design and Optimization (DDOP), Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI)SaarbrückenGermany
- Department of Pharmacy, Saarland UniversitySaarbrückenGermany
- Stratingh Institute for Chemistry, University of GroningenGroningenNetherlands
| | - Birgit Habenstein
- Institute of Chemistry & Biology of Membranes & Nanoobjects (UMR5248 CBMN), IECB, CNRS, Université Bordeaux, Institut Polytechnique BordeauxPessacFrance
| | - Marc Bramkamp
- Biozentrum, Ludwig-Maximilians-Universität MünchenMünchenGermany
- Institute for General Microbiology, Christian-Albrechts-UniversityKielGermany
| | - Dirk-Jan Scheffers
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningenNetherlands
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8
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Sharifzadeh S, Dempwolff F, Kearns DB, Carlson EE. Harnessing β-Lactam Antibiotics for Illumination of the Activity of Penicillin-Binding Proteins in Bacillus subtilis. ACS Chem Biol 2020; 15:1242-1251. [PMID: 32155044 DOI: 10.1021/acschembio.9b00977] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Selective chemical probes enable individual investigation of penicillin-binding proteins (PBPs) and provide critical information about their enzymatic activity with spatial and temporal resolution. To identify scaffolds for novel probes to study peptidoglycan biosynthesis in Bacillus subtilis, we evaluated the PBP inhibition profiles of 21 β-lactam antibiotics from different structural subclasses using a fluorescence-based assay. Most compounds readily labeled PBP1, PBP2a, PBP2b, or PBP4. Almost all penicillin scaffolds were coselective for all or combinations of PBP2a, 2b, and 4. Cephalosporins, on the other hand, possessed the lowest IC50 values for PBP1 alone or along with PBP4 (ceftriaxone, cefoxitin) and 2b (cefotaxime) or 2a, 2b, and 4 (cephalothin). Overall, five selective inhibitors for PBP1 (aztreonam, faropenem, piperacillin, cefuroxime, and cefsulodin), one selective inhibitor for PBP5 (6-aminopenicillanic acid), and various coselective inhibitors for other PBPs in B. subtilis were discovered. Surprisingly, carbapenems strongly inhibited PBP3, formerly shown to have low affinity for β-lactams and speculated to be involved in β-lactam resistance in B. subtilis. To investigate the specific roles of PBP3, we developed activity-based probes based on the meropenem core and utilized them to monitor the activity of PBP3 in living cells. We showed that PBP3 activity localizes as patches in single cells and concentrates as a ring at the septum and the division site during the cell growth cycle. Our activity-based approach enabled spatial resolution of the transpeptidation activity of individual PBPs in this model microorganism, which was not possible with previous chemical and biological approaches.
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Affiliation(s)
| | - Felix Dempwolff
- Department of Biology, Indiana University, Bloomington, Indiana 47405, United States
| | - Daniel B. Kearns
- Department of Biology, Indiana University, Bloomington, Indiana 47405, United States
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9
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Fluorescent amino acids as versatile building blocks for chemical biology. Nat Rev Chem 2020; 4:275-290. [PMID: 37127957 DOI: 10.1038/s41570-020-0186-z] [Citation(s) in RCA: 108] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2020] [Indexed: 12/13/2022]
Abstract
Fluorophores have transformed the way we study biological systems, enabling non-invasive studies in cells and intact organisms, which increase our understanding of complex processes at the molecular level. Fluorescent amino acids have become an essential chemical tool because they can be used to construct fluorescent macromolecules, such as peptides and proteins, without disrupting their native biomolecular properties. Fluorescent and fluorogenic amino acids with unique photophysical properties have been designed for tracking protein-protein interactions in situ or imaging nanoscopic events in real time with high spatial resolution. In this Review, we discuss advances in the design and synthesis of fluorescent amino acids and how they have contributed to the field of chemical biology in the past 10 years. Important areas of research that we review include novel methodologies to synthesize building blocks with tunable spectral properties, their integration into peptide and protein scaffolds using site-specific genetic encoding and bioorthogonal approaches, and their application to design novel artificial proteins, as well as to investigate biological processes in cells by means of optical imaging.
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Kuru E, Radkov A, Meng X, Egan A, Alvarez L, Dowson A, Booher G, Breukink E, Roper DI, Cava F, Vollmer W, Brun Y, VanNieuwenhze MS. Mechanisms of Incorporation for D-Amino Acid Probes That Target Peptidoglycan Biosynthesis. ACS Chem Biol 2019; 14:2745-2756. [PMID: 31743648 PMCID: PMC6929685 DOI: 10.1021/acschembio.9b00664] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
![]()
Bacteria exhibit a myriad of different morphologies,
through the
synthesis and modification of their essential peptidoglycan (PG) cell
wall. Our discovery of a fluorescent D-amino acid (FDAA)-based PG labeling approach provided a powerful method
for observing how these morphological changes occur. Given that PG
is unique to bacterial cells and a common target for antibiotics,
understanding the precise mechanism(s) for incorporation of (F)DAA-based
probes is a crucial determinant in understanding the role of PG synthesis
in bacterial cell biology and could provide a valuable tool in the
development of new antimicrobials to treat drug-resistant antibacterial
infections. Here, we systematically investigate the mechanisms of
FDAA probe incorporation into PG using two model organisms Escherichia coli (Gram-negative) and Bacillus subtilis (Gram-positive). Our in vitro and in vivo data unequivocally demonstrate
that these bacteria incorporate FDAAs using two extracytoplasmic pathways:
through activity of their D,D-transpeptidases, and,
if present, by their L,D-transpeptidases and not
via cytoplasmic incorporation into a D-Ala-D-Ala
dipeptide precursor. Our data also revealed the unprecedented finding
that the DAA-drug, D-cycloserine, can be incorporated into
peptide stems by each of these transpeptidases, in addition to its
known inhibitory activity against D-alanine racemase and D-Ala-D-Ala ligase. These mechanistic findings enabled
development of a new, FDAA-based, in vitro labeling approach that
reports on subcellular distribution of muropeptides, an especially
important attribute to enable the study of bacteria with poorly defined
growth modes. An improved understanding of the incorporation mechanisms
utilized by DAA-based probes is essential when interpreting results
from high resolution experiments and highlights the antimicrobial
potential of synthetic DAAs.
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Affiliation(s)
- Erkin Kuru
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Atanas Radkov
- Department of Biochemistry and Biophysics, UCSF School of Medicine, San Francisco, California 94158, United States
| | - Xin Meng
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Alexander Egan
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4AX, United Kingdom
| | - Laura Alvarez
- Department of Molecular Biology, Umeå University, SE-901 87, Umeå, Sweden
| | - Amanda Dowson
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Garrett Booher
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Eefjan Breukink
- Department of Chemistry, Utrecht University, 3584 CH, Utrecht, Netherlands
| | - David I. Roper
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Felipe Cava
- Department of Molecular Biology, Umeå University, SE-901 87, Umeå, Sweden
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4AX, United Kingdom
| | - Yves Brun
- Department of Microbiology, Infectious Diseases, and Immunology, Faculty of Medicine, Université de Montréal, Montréal, Canada
| | - Michael S. VanNieuwenhze
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, United States
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Hsu YP, Booher G, Egan A, Vollmer W, VanNieuwenhze MS. d-Amino Acid Derivatives as in Situ Probes for Visualizing Bacterial Peptidoglycan Biosynthesis. Acc Chem Res 2019; 52:2713-2722. [PMID: 31419110 DOI: 10.1021/acs.accounts.9b00311] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The bacterial cell wall is composed of membrane layers and a rigid yet flexible scaffold called peptidoglycan (PG). PG provides mechanical strength to enable bacteria to resist damage from the environment and lysis due to high internal turgor. PG also has a critical role in dictating bacterial cell morphology. The essential nature of PG for bacterial propagation, as well as its value as an antibiotic target, has led to renewed interest in the study of peptidoglycan biosynthesis. However, significant knowledge gaps remain that must be addressed before a clear understanding of peptidoglycan synthesis and dynamics is realized. For example, the enzymes involved in the PG biosynthesis pathway have not been fully characterized. Our understanding of PG biosynthesis has been frequently revamped by the discovery of novel enzymes or newly characterized functions of known enzymes. In addition, we do not clearly know how the respective activities of these enzymes are coordinated with each other and how they control the spatial and temporal dynamics of PG synthesis. The emergence of molecular probes and imaging techniques has significantly advanced the study PG synthesis and modification. Prior efforts utilized the specificity of PG-targeting antibiotics and proteins to develop PG-specific probes, such as fluorescent vancomycin and fluorescent wheat germ agglutinin. However, these probes suffer from limitations due to toxic effects toward bacterial cells and poor membrane permeability. To address these issues, we designed and introduced a family of novel molecular probes, fluorescent d-amino acids (FDAAs), which are covalently incorporated into PG through the activities of endogenous bacterial transpeptidases. Their high biocompatibility and PG specificity have made them powerful tools for labeling peptidoglycan. In addition, their enzyme-mediated incorporation faithfully reflects the activity of PG synthases, providing a direct in situ method for studying PG formation during the bacterial life cycle. In this Account, we describe our efforts directed at the development of FDAAs and their derivatives. These probes have enabled for the first time the ability to visualize PG synthesis in live bacterial cells and in real time. We summarize experimental evidence for FDAA incorporation into PG and the enzyme-mediated incorporation pathway. We demonstrate various applications of FDAAs, including bacterial morphology analyses, PG growth model studies, investigation of PG-enzyme correlation, in vitro PG synthase activity assays, and antibiotic inhibition tests. Finally, we discuss the current limitations of the probes and our ongoing efforts to improve them. We are confident that these probes will prove to be valuable tools that will enable the discovery of new antibiotic targets and expand the available arsenal directed at the public health threat posed by antibiotic resistance.
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Affiliation(s)
- Yen-Pang Hsu
- Department of Molecular and Cellular Biochemistry, Indiana University Bloomington, Simon Hall 001, 212 South Hawthorne Drive, Bloomington, Indiana 47405, United States
| | - Garrett Booher
- Department of Molecular and Cellular Biochemistry, Indiana University Bloomington, Simon Hall 001, 212 South Hawthorne Drive, Bloomington, Indiana 47405, United States
| | - Alexander Egan
- The Centre for Bacterial Cell Biology, Newcastle University, Richardson Road, Newcastle upon Tyne NE2 4AX, United Kingdom
| | - Waldemar Vollmer
- The Centre for Bacterial Cell Biology, Newcastle University, Richardson Road, Newcastle upon Tyne NE2 4AX, United Kingdom
| | - Michael S. VanNieuwenhze
- Department of Molecular and Cellular Biochemistry, Indiana University Bloomington, Simon Hall 001, 212 South Hawthorne Drive, Bloomington, Indiana 47405, United States
- Department of Chemistry, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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12
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van der Aart LT, Spijksma GK, Harms A, Vollmer W, Hankemeier T, van Wezel GP. High-Resolution Analysis of the Peptidoglycan Composition in Streptomyces coelicolor. J Bacteriol 2018; 200:e00290-18. [PMID: 30061355 PMCID: PMC6153666 DOI: 10.1128/jb.00290-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 07/27/2018] [Indexed: 11/20/2022] Open
Abstract
The bacterial cell wall maintains cell shape and protects against bursting by turgor. A major constituent of the cell wall is peptidoglycan (PG), which is continuously modified to enable cell growth and differentiation through the concerted activity of biosynthetic and hydrolytic enzymes. Streptomycetes are Gram-positive bacteria with a complex multicellular life style alternating between mycelial growth and the formation of reproductive spores. This involves cell wall remodeling at apical sites of the hyphae during cell elongation and autolytic degradation of the vegetative mycelium during the onset of development and antibiotic production. Here, we show that there are distinct differences in the cross-linking and maturation of the PGs between exponentially growing vegetative hyphae and the aerial hyphae that undergo sporulation. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis identified over 80 different muropeptides, revealing that major PG hydrolysis takes place over the course of mycelial growth. Half of the dimers lacked one of the disaccharide units in transition-phase cells, most likely due to autolytic activity. The deacetylation of MurNAc to MurN was particularly pronounced in spores and strongly reduced in sporulation mutants with a deletion of bldD or whiG, suggesting that MurN is developmentally regulated. Altogether, our work highlights the dynamic and growth phase-dependent changes in the composition of the PG in StreptomycesIMPORTANCE Streptomycetes are bacteria with a complex lifestyle and are model organisms for bacterial multicellularity. From a single spore, a large multigenomic multicellular mycelium is formed, which differentiates to form spores. Programmed cell death is an important event during the onset of morphological differentiation. In this work, we provide new insights into the changes in the peptidoglycan composition and over time, highlighting changes over the course of development and between growing mycelia and spores. This revealed dynamic changes in the peptidoglycan when the mycelia aged, with extensive peptidoglycan hydrolysis and, in particular, an increase in the proportion of 3-3 cross-links. Additionally, we identified a muropeptide that accumulates predominantly in the spores and may provide clues toward spore development.
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Affiliation(s)
- Lizah T van der Aart
- Molecular Biotechnology, Institute of Biology, Leiden University, Leiden, The Netherlands
| | - Gerwin K Spijksma
- Division of Analytical Biosciences, Leiden Academic Center for Drug Research, Leiden University, Leiden, The Netherlands
| | - Amy Harms
- Division of Analytical Biosciences, Leiden Academic Center for Drug Research, Leiden University, Leiden, The Netherlands
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Thomas Hankemeier
- Division of Analytical Biosciences, Leiden Academic Center for Drug Research, Leiden University, Leiden, The Netherlands
| | - Gilles P van Wezel
- Molecular Biotechnology, Institute of Biology, Leiden University, Leiden, The Netherlands
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
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13
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Lambert A, Vanhecke A, Archetti A, Holden S, Schaber F, Pincus Z, Laub MT, Goley E, Manley S. Constriction Rate Modulation Can Drive Cell Size Control and Homeostasis in C. crescentus. iScience 2018; 4:180-189. [PMID: 30240739 PMCID: PMC6147026 DOI: 10.1016/j.isci.2018.05.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/04/2018] [Accepted: 05/24/2018] [Indexed: 11/24/2022] Open
Abstract
Rod-shaped bacteria typically grow first via sporadic and dispersed elongation along their lateral walls and then via a combination of zonal elongation and constriction at the division site to form the poles of daughter cells. Although constriction comprises up to half of the cell cycle, its impact on cell size control and homeostasis has rarely been considered. To reveal the roles of cell elongation and constriction in bacterial size regulation during cell division, we captured the shape dynamics of Caulobacter crescentus with time-lapse structured illumination microscopy and used molecular markers as cell-cycle landmarks. We perturbed the constriction rate using a hyperconstriction mutant or fosfomycin ([(2R,3S)-3-methyloxiran-2-yl]phosphonic acid) inhibition. We report that the constriction rate contributes to both size control and homeostasis, by determining elongation during constriction and by compensating for variation in pre-constriction elongation on a single-cell basis. Perturbing constriction rate changes cell length Faster constriction rate results in blunter cell poles Early constriction rate modulation balances elongation before and during constriction We propose that constriction rate is set by the accumulation of precursors during elongation
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Affiliation(s)
- Ambroise Lambert
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Aster Vanhecke
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Anna Archetti
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Seamus Holden
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
| | - Felix Schaber
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Zachary Pincus
- Department of Genetics, Washington University in St. Louis, St. Louis, MO 63110, USA; Department of Developmental Biology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Michael T Laub
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, MassachusettsInstitute of Technology, Cambridge, MA 02139, USA
| | - Erin Goley
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Suliana Manley
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
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14
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Abstract
Peptidoglycan is an essential component of the cell wall that protects bacteria from environmental stress. A carefully coordinated biosynthesis of peptidoglycan during cell elongation and division is required for cell viability. This biosynthesis involves sophisticated enzyme machineries that dynamically synthesize, remodel, and degrade peptidoglycan. However, when and where bacteria build peptidoglycan, and how this is coordinated with cell growth, have been long-standing questions in the field. The improvement of microscopy techniques has provided powerful approaches to study peptidoglycan biosynthesis with high spatiotemporal resolution. Recent development of molecular probes further accelerated the growth of the field, which has advanced our knowledge of peptidoglycan biosynthesis dynamics and mechanisms. Here, we review the technologies for imaging the bacterial cell wall and its biosynthesis activity. We focus on the applications of fluorescent d-amino acids, a newly developed type of probe, to visualize and study peptidoglycan synthesis and dynamics, and we provide direction for prospective research.
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Affiliation(s)
- Atanas D Radkov
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.,Current affiliation: Biophysics and Biochemistry Department, University of California, San Francisco, California 94158, USA;
| | - Yen-Pang Hsu
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA; , ,
| | - Garrett Booher
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA; , ,
| | - Michael S VanNieuwenhze
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.,Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA; , ,
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15
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Li K, Yuan XX, Sun HM, Zhao LS, Tang R, Chen ZH, Qin QL, Chen XL, Zhang YZ, Su HN. Atomic Force Microscopy of Side Wall and Septa Peptidoglycan From Bacillus subtilis Reveals an Architectural Remodeling During Growth. Front Microbiol 2018; 9:620. [PMID: 29651285 PMCID: PMC5884923 DOI: 10.3389/fmicb.2018.00620] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 03/16/2018] [Indexed: 02/02/2023] Open
Abstract
Peptidoglycan is the fundamental structural constituent of the bacterial cell wall. Despite many years of research, the architecture of peptidoglycan is still largely elusive. Here, we report the high-resolution architecture of peptidoglycan from the model Gram-positive bacterium Bacillus subtilis. We provide high-resolution evidence of peptidoglycan architecture remodeling at different growth stages. Side wall peptidoglycan from B. subtilis strain AS1.398 changed from an irregular architecture in exponential growth phase to an ordered cable-like architecture in stationary phase. Thickness of side wall peptidoglycan was found to be related with growth stages, with a slight increase after transition to stationary phase. Septal disks were synthesized progressively toward the center, while the surface features were less clear than those imaged with side walls. Compared with previous studies, our results revealed slight differences in architecture of peptidoglycan from different B. subtilis strains, expanding our knowledge about the architectural features of B. subtilis peptidoglycan.
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Affiliation(s)
- Kang Li
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China
| | - Xiao-Xue Yuan
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China
| | - He-Min Sun
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China
| | - Long-Sheng Zhao
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China
| | - Ruocong Tang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China
| | - Zhi-Hua Chen
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China
| | - Qi-Long Qin
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China
| | - Xiu-Lan Chen
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China
| | - Yu-Zhong Zhang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.,College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Hai-Nan Su
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Jinan, China.,College of Marine Life Sciences, Ocean University of China, Qingdao, China
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16
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Zhao H, Patel V, Helmann JD, Dörr T. Don't let sleeping dogmas lie: new views of peptidoglycan synthesis and its regulation. Mol Microbiol 2017; 106:847-860. [PMID: 28975672 DOI: 10.1111/mmi.13853] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2017] [Indexed: 12/24/2022]
Abstract
Bacterial cell wall synthesis is the target for some of our most powerful antibiotics and has thus been the subject of intense research focus for more than 50 years. Surprisingly, we still lack a fundamental understanding of how bacteria build, maintain and expand their cell wall. Due to technical limitations, directly testing hypotheses about the coordination and biochemistry of cell wall synthesis enzymes or architecture has been challenging, and interpretation of data has therefore often relied on circumstantial evidence and implicit assumptions. A number of recent papers have exploited new technologies, like single molecule tracking and real-time, high resolution temporal mapping of cell wall synthesis processes, to address fundamental questions of bacterial cell wall biogenesis. The results have challenged established dogmas and it is therefore timely to integrate new data and old observations into a new model of cell wall biogenesis in rod-shaped bacteria.
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Affiliation(s)
- Heng Zhao
- Department of Microbiology, Cornell University, Ithaca, NY 14853-8101, USA
| | - Vaidehi Patel
- Department of Microbiology, Cornell University, Ithaca, NY 14853-8101, USA
| | - John D Helmann
- Department of Microbiology, Cornell University, Ithaca, NY 14853-8101, USA
| | - Tobias Dörr
- Department of Microbiology, Cornell University, Ithaca, NY 14853-8101, USA.,Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
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17
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Hsu YP, Rittichier J, Kuru E, Yablonowski J, Pasciak E, Tekkam S, Hall E, Murphy B, Lee TK, Garner EC, Huang KC, Brun YV, VanNieuwenhze MS. Full color palette of fluorescent d-amino acids for in situ labeling of bacterial cell walls. Chem Sci 2017; 8:6313-6321. [PMID: 28989665 PMCID: PMC5628581 DOI: 10.1039/c7sc01800b] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Accepted: 07/06/2017] [Indexed: 01/01/2023] Open
Abstract
Fluorescent d-amino acids (FDAAs) enable efficient in situ labeling of peptidoglycan in diverse bacterial species. Conducted by enzymes involved in peptidoglycan biosynthesis, FDAA labeling allows specific probing of cell wall formation/remodeling activity, bacterial growth and cell morphology. Their broad application and high biocompatibility have made FDAAs an important and effective tool for studies of peptidoglycan synthesis and dynamics, which, in turn, has created a demand for the development of new FDAA probes. Here, we report the synthesis of new FDAAs, with emission wavelengths that span the entire visible spectrum. We also provide data to characterize their photochemical and physical properties, and we demonstrate their utility for visualizing peptidoglycan synthesis in Gram-negative and Gram-positive bacterial species. Finally, we show the permeability of FDAAs toward the outer-membrane of Gram-negative organisms, pinpointing the probes available for effective labeling in these species. This improved FDAA toolkit will enable numerous applications for the study of peptidoglycan biosynthesis and dynamics.
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Affiliation(s)
- Yen-Pang Hsu
- Department of Molecular and Cellular Biochemistry , Indiana University , Bloomington , IN 47405 , USA .
| | | | - Erkin Kuru
- Department of Molecular and Cellular Biochemistry , Indiana University , Bloomington , IN 47405 , USA .
| | - Jacob Yablonowski
- Department of Molecular and Cellular Biochemistry , Indiana University , Bloomington , IN 47405 , USA .
| | - Erick Pasciak
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA
| | - Srinivas Tekkam
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA
| | - Edward Hall
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA
| | - Brennan Murphy
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA
| | - Timothy K Lee
- Department of Bioengineering , Stanford University , Stanford , CA 94305 , USA
| | - Ethan C Garner
- Molecular and Cellular Biology (FAS) Center for Systems Biology , Harvard University , Cambridge , Massachusetts 02138 , USA
| | - Kerwyn Casey Huang
- Department of Bioengineering , Stanford University , Stanford , CA 94305 , USA
- Department of Microbiology and Immunology , Stanford University School of Medicine , Stanford , CA 94305 , USA
| | - Yves V Brun
- Department of Biology , Indiana University , Bloomington , IN 47405 , USA .
| | - Michael S VanNieuwenhze
- Department of Molecular and Cellular Biochemistry , Indiana University , Bloomington , IN 47405 , USA .
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA
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18
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Sassine J, Xu M, Sidiq KR, Emmins R, Errington J, Daniel RA. Functional redundancy of division specific penicillin-binding proteins in Bacillus subtilis. Mol Microbiol 2017; 106:304-318. [PMID: 28792086 PMCID: PMC5656894 DOI: 10.1111/mmi.13765] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2017] [Indexed: 12/30/2022]
Abstract
Bacterial cell division involves the dynamic assembly of a diverse set of proteins that coordinate the invagination of the cell membrane and synthesis of cell wall material to create the new cell poles of the separated daughter cells. Penicillin-binding protein PBP 2B is a key cell division protein in Bacillus subtilis proposed to have a specific catalytic role in septal wall synthesis. Unexpectedly, we find that a catalytically inactive mutant of PBP 2B supports cell division, but in this background the normally dispensable PBP 3 becomes essential. Phenotypic analysis of pbpC mutants (encoding PBP 3) shows that PBP 2B has a crucial structural role in assembly of the division complex, independent of catalysis, and that its biochemical activity in septum formation can be provided by PBP 3. Bioinformatic analysis revealed a close sequence relationship between PBP 3 and Staphylococcus aureus PBP 2A, which is responsible for methicillin resistance. These findings suggest that mechanisms for rescuing cell division when the biochemical activity of PBP 2B is perturbed evolved prior to the clinical use of β-lactams.
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Affiliation(s)
- Jad Sassine
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4AH, UK
| | - Meizhu Xu
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4AH, UK
| | - Karzan R Sidiq
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4AH, UK
| | - Robyn Emmins
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4AH, UK
| | - Jeff Errington
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4AH, UK
| | - Richard A Daniel
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4AH, UK
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19
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Sabulski MJ, Pidgeon SE, Pires MM. Immuno-targeting of Staphylococcus aureus via surface remodeling complexes. Chem Sci 2017; 8:6804-6809. [PMID: 29147504 PMCID: PMC5643955 DOI: 10.1039/c7sc02721d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 08/20/2017] [Indexed: 12/28/2022] Open
Abstract
Agents with novel mechanisms of action are needed to complement traditional antibiotics. Towards these goals, we have exploited the surface-homing properties of vancomycin to tag the surface of Gram-positive pathogens with immune cell attractants in two unique modes. First, vancomycin was conjugated to the small molecule hapten 2,4-dinitrophenol (DNP) to promote bacterial opsonization. Second, we built on these results by improving the tagging specificity and mechanism of incorporation by coupling it to a sortase A substrate peptide. We demonstrated, for the first time, that the surface of Staphylococcus aureus (S. aureus) can be metabolically labeled in live Caenorhabditis elegans hosts. These constructs represent a class of promising narrow-spectrum agents that target S. aureus for opsonization and establish a new surface labeling modality in live host organisms, which should be a powerful tool in dissecting features of host-pathogen interactions.
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Affiliation(s)
- Mary J Sabulski
- Department of Chemistry , Lehigh University , 6 E Packer Ave. , Bethlehem , PA 18015 , USA .
| | - Sean E Pidgeon
- Department of Chemistry , Lehigh University , 6 E Packer Ave. , Bethlehem , PA 18015 , USA .
| | - Marcos M Pires
- Department of Chemistry , Lehigh University , 6 E Packer Ave. , Bethlehem , PA 18015 , USA .
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