1
|
Bechtel TD, Hershelman J, Ghoshal M, McLandsborough L, Gibbons JG. Chemical mutagenesis of Listeria monocytogenes for increased tolerance to benzalkonium chloride shows independent genetic underpinnings and off-target antibiotic resistance. PLoS One 2024; 19:e0305663. [PMID: 39028728 PMCID: PMC11259264 DOI: 10.1371/journal.pone.0305663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 06/02/2024] [Indexed: 07/21/2024] Open
Abstract
Listeria monocytogenes, a potentially fatal foodborne pathogen commonly found in food processing facilities, creates a significant economic burden that totals more than $2 billion annually in the United States due to outbreaks. Quaternary ammonium compounds (QACs), including benzalkonium chloride (BAC), are among the most widely used sanitizers to inhibit the growth and spread of L. monocytogenes from food processing facilities. However, resistance to QACs has been increasing in L. monocytogenes and different genetic mechanisms conferring resistance have been discovered. Here, we used ethyl methanesulfonate (EMS) to chemically mutagenize the BAC-susceptible strain, L. monocytogenes FSL-N1-304. We isolated two mutants with increased tolerance to BAC compared to the parental strain. Next, we assessed the off-target effect of increased tolerance to BAC by measuring the minimum inhibitory concentrations (MICs) of a diverse set of antibiotics, revealing that mut-1 and mut-2 displayed significantly increased resistance to fluoroquinolone antibiotics compared to the parental strain. A hemolysis assay was then used to investigate a potential correlation between BAC tolerance and virulence. Interestingly, mut-1 and mut-2 both exhibited significantly higher hemolysis percentage than the parental strain. We then sequenced the genomes of the parental strain and both mutants to identify mutations that may be involved in the increased resistance to BAC. We identified 3 and 29 mutations in mut-1 and mut-2, respectively. mut-1 contained nonsynonymous mutations in dagK (a diacylglycerol kinase), lmo2768 (a permease-encoding gene), and lmo0186 (resuscitation promoting factor). mut-2 contained a nonsense mutation in the nucleotide excision repair enzyme UvrABC system protein B encoding gene, uvrB, which likely accounts for the higher number of mutations observed. Transcriptome analysis in the presence of BAC revealed that genes related to the phosphotransferase system and internalins were up-regulated in both mutants, suggesting their significance in the BAC stress response. These two mutants provide insights into alternative mechanisms for increased BAC tolerance and could further our understanding of how L. monocytogenes persists in the food processing environment.
Collapse
Affiliation(s)
- Tyler D. Bechtel
- Department of Food Science, University of Massachusetts, Amherst, MA, United States of America
| | - Julia Hershelman
- Department of Food Science, University of Massachusetts, Amherst, MA, United States of America
- Department of Microbiology, University of Massachusetts, Amherst, MA, United States of America
| | - Mrinalini Ghoshal
- Department of Food Science, University of Massachusetts, Amherst, MA, United States of America
- Department of Microbiology, University of Massachusetts, Amherst, MA, United States of America
| | - Lynne McLandsborough
- Department of Microbiology, University of Massachusetts, Amherst, MA, United States of America
| | - John G. Gibbons
- Department of Food Science, University of Massachusetts, Amherst, MA, United States of America
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA, United States of America
- Organismic & Evolutionary Biology Graduate Program, University of Massachusetts, Amherst, MA, United States of America
| |
Collapse
|
2
|
Baran A, Ertaş E, Baran MF, Eftekhari A, Gunes Z, Keskin C, Usanov SA, Khalilov R. Green-Synthesized Characterization, Antioxidant and Antibacterial Applications of CtAC/MNPs-Ag Nanocomposites. Pharmaceuticals (Basel) 2024; 17:772. [PMID: 38931439 PMCID: PMC11206647 DOI: 10.3390/ph17060772] [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: 05/09/2024] [Revised: 06/04/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024] Open
Abstract
The emergence of antibiotic resistance, caused by the improper use of antibiotics, is a significant challenge in combating infectious diseases, leading to millions of annual fatalities. The occurrence of antimicrobial side effects catalyzes the investigation of novel antimicrobial compounds and sources of drugs. Consequently, the research on biological activity that is conducted on plants, plant extracts, and compounds that are produced from plant components is of utmost significance. In this study, CtAC/MNPs were obtained by the reaction of activated carbon (AC) obtained from the fruits of the Celtis tournefortii (Ct) plant and magnetic nanoparticles (MNPs), and a CtAC/MNPs-Ag nanocomposite was synthesized by the reduction in silver ions added to the reaction. The synthesized CtAC/MNPs and CtAC/MNPs-Ag nanocomposites were analyzed spectroscopically (FTIR, XRD), microscopically (SEM, EDX), optically (DLS), electrochemically (zeta potential) and magnetically (VSM). The antibacterial activities of CtAC/MNPs and CtAC/MNPs-Ag nanocomposites against S. aureus and E. coli were investigated by microdilution method using minimal inhibitory concentration (MIC) and disk diffusion methods. Antioxidant activity study, including total phenolic content and DPPH and cuprac assays, revealed the remarkable effect of the CtAC/MNPs-Ag nanocomposite. This study has the advantages of obtaining CtAC/MNPs and CtAC/MNPs-Ag nanocomposites in a short time without requiring energy, and most importantly, the reaction takes place without using any toxic substances. In addition, according to the data obtained in the study, the CtAC/MNPs-Ag nanocomposite is thought to shed light on biomedical research.
Collapse
Affiliation(s)
- Ayşe Baran
- Department of Biology, Graduate Education Institute, Mardin Artuklu University, Mardin 47200, Turkey;
| | - Erdal Ertaş
- Department of Food Technology, Vocational School of Technical Sciences, Batman University, Batman 72000, Turkey; (E.E.); (M.F.B.)
| | - Mehmet Fırat Baran
- Department of Food Technology, Vocational School of Technical Sciences, Batman University, Batman 72000, Turkey; (E.E.); (M.F.B.)
| | - Aziz Eftekhari
- Department of Biochemistry, Faculty of Science, Ege University, Izmir 35040, Turkey
- Department of Life Sciences, Western Caspian University, Baku AZ1072, Azerbaijan
| | - Zübeyir Gunes
- Department of Crops and Animal Production, Mardin Artuklu University, Mardin 47200, Turkey;
| | - Cumali Keskin
- Department of Medical Services, Vocational School of Health Services, Mardin Artuklu University, Mardin 47200, Turkey;
| | - Sergey A. Usanov
- Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus, 220141 Minsk, Belarus
| | - Rovshan Khalilov
- Department of Biophysics and Biochemistry, Baku State University, Baku AZ1148, Azerbaijan
- Institute of Radiation Problems, Ministry of Science and Education Republic of Azerbaijan, Baku AZ1143, Azerbaijan
| |
Collapse
|
3
|
Li Y, Luo L, Wang W, Hong B, Ma Y, Wang J. Characterization of a cell wall hydrolase with high activity against vegetative cells, spores and biofilm of Bacillus cereus. Int J Food Microbiol 2024; 414:110617. [PMID: 38335884 DOI: 10.1016/j.ijfoodmicro.2024.110617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 12/17/2023] [Accepted: 02/04/2024] [Indexed: 02/12/2024]
Abstract
Bacillus cereus is a prevalent foodborne pathogen that induces food poisoning symptoms such as vomiting and diarrhea. Its capacity to form spores and biofilm enables it to withstand disinfectants and antimicrobials, leading to persistent contamination during food processing. Consequently, it is necessary to develop novel and efficient antimicrobial agents to control B. cereus, its spores, and biofilms. Peptidoglycan hydrolases have emerged as a promising and eco-friendly alternative owing to their specific lytic activity against pathogenic bacteria. Here, we identified and characterized a Lysozyme-like cell wall hydrolase Lys14579, from the genome of B. cereus ATCC 14579. Recombinant Lys14579 specifically lysed B. cereus without affecting other bacteria. Lys14579 exhibited strong lytic activity against B. cereus, effectively lysing B. cereus cell within 20 min at low concentration (10 μg/mL). It also inhibited the germination of B. cereus spores and prevented biofilm formation at 12.5 μg/mL. Moreover, Lys14579 displayed good antimicrobial stability with negligible hemolysis in mouse red blood cells and no cytotoxicity against RAW264.7 cells. Notably, Lys14579 effectively inhibited B. cereus in boiled rice and minced meat in a dose-dependent manner. Furthermore, bioinformatics analysis and point mutagenesis experiments revealed that Glu-47 was the catalytic site, and Asp-57, Gln-60, Ser-61 and Glu-63 were active-site residues related with the cell wall lytic activity. Taken together, Lys14579 could be a promising biocontrol agent against vegetative cells, spores, and biofilm of B. cereus in food industry.
Collapse
Affiliation(s)
- Yanmei Li
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China
| | - Lun Luo
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China
| | - Wenhai Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China
| | - Bin Hong
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China
| | - Yi Ma
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Jufang Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China.
| |
Collapse
|
4
|
Hillman A, Hyland SN, Wodzanowski KA, Moore DL, Ratna S, Jemas A, Sandles LMD, Chaya T, Ghosh A, Fox JM, Grimes CL. Minimalist Tetrazine N-Acetyl Muramic Acid Probes for Rapid and Efficient Labeling of Commensal and Pathogenic Peptidoglycans in Living Bacterial Culture and During Macrophage Invasion. J Am Chem Soc 2024; 146:6817-6829. [PMID: 38427023 PMCID: PMC10941766 DOI: 10.1021/jacs.3c13644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 03/02/2024]
Abstract
N-Acetyl muramic acid (NAM) probes containing alkyne or azide groups are commonly used to investigate aspects of cell wall synthesis because of their small size and ability to incorporate into bacterial peptidoglycan (PG). However, copper-catalyzed alkyne-azide cycloaddition (CuAAC) reactions are not compatible with live cells, and strain-promoted alkyne-azide cycloaddition (SPAAC) reaction rates are modest and, therefore, not as desirable for tracking the temporal alterations of bacterial cell growth, remodeling, and division. Alternatively, the tetrazine-trans-cyclooctene ligation (Tz-TCO), which is the fastest known bioorthogonal reaction and not cytotoxic, allows for rapid live-cell labeling of PG at biologically relevant time scales and concentrations. Previous work to increase reaction kinetics on the PG surface by using tetrazine probes was limited because of low incorporation of the probe. Described here are new approaches to construct a minimalist tetrazine (Tz)-NAM probe utilizing recent advancements in asymmetric tetrazine synthesis. This minimalist Tz-NAM probe was successfully incorporated into pathogenic and commensal bacterial PG where fixed and rapid live-cell, no-wash labeling was successful in both free bacterial cultures and in coculture with human macrophages. Overall, this probe allows for expeditious labeling of bacterial PG, thereby making it an exceptional tool for monitoring PG biosynthesis for the development of new antibiotic screens. The versatility and selectivity of this probe will allow for real-time interrogation of the interactions of bacterial pathogens in a human host and will serve a broader utility for studying glycans in multiple complex biological systems.
Collapse
Affiliation(s)
- Ashlyn
S. Hillman
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Stephen N. Hyland
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Kimberly A. Wodzanowski
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - DeVonte L. Moore
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Sushanta Ratna
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Andrew Jemas
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Liam-Michael D. Sandles
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Timothy Chaya
- Department
of Plant and Soil Sciences, University of
Delaware, Newark, Delaware 19716, United States
| | - Arit Ghosh
- Delaware
Biotechnology Institute, UDEL Flow Cytometry Core, University of Delaware, Newark, Delaware 19716, United States
| | - Joseph M. Fox
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
- Department
of Materials Science and Engineering, University
of Delaware, Newark, Delaware 19716, United States
| | - Catherine L. Grimes
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
- Department
of Biological Sciences, University of Delaware, Newark, Delaware 19716, United States
| |
Collapse
|
5
|
Koatale P, Welling MM, Ndlovu H, Kgatle M, Mdanda S, Mdlophane A, Okem A, Takyi-Williams J, Sathekge MM, Ebenhan T. Insights into Peptidoglycan-Targeting Radiotracers for Imaging Bacterial Infections: Updates, Challenges, and Future Perspectives. ACS Infect Dis 2024; 10:270-286. [PMID: 38290525 PMCID: PMC10862554 DOI: 10.1021/acsinfecdis.3c00443] [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: 08/28/2023] [Revised: 12/16/2023] [Accepted: 12/18/2023] [Indexed: 02/01/2024]
Abstract
The unique structural architecture of the peptidoglycan allows for the stratification of bacteria as either Gram-negative or Gram-positive, which makes bacterial cells distinguishable from mammalian cells. This classification has received attention as a potential target for diagnostic and therapeutic purposes. Bacteria's ability to metabolically integrate peptidoglycan precursors during cell wall biosynthesis and recycling offers an opportunity to target and image pathogens in their biological state. This Review explores the peptidoglycan biosynthesis for bacteria-specific targeting for infection imaging. Current and potential radiolabeled peptidoglycan precursors for bacterial infection imaging, their development status, and their performance in vitro and/or in vivo are highlighted. We conclude by providing our thoughts on how to shape this area of research for future clinical translation.
Collapse
Affiliation(s)
- Palesa
C. Koatale
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Mick M. Welling
- Interventional
Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Honest Ndlovu
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Mankgopo Kgatle
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Sipho Mdanda
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Amanda Mdlophane
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Ambrose Okem
- Department
of Anaesthesia, School of Clinical Medicine, University of Witwatersrand, 2050 Johannesburg, South Africa
| | - John Takyi-Williams
- Pharmacokinetic
and Mass Spectrometry Core, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Mike M. Sathekge
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
| | - Thomas Ebenhan
- Department
of Nuclear Medicine, University of Pretoria, 0001 Pretoria, South Africa
- Nuclear
Medicine Research Infrastructure (NuMeRI) NPC, 0001 Pretoria, South Africa
- DSI/NWU Pre-clinical
Drug Development Platform, North West University, 2520 Potchefstroom, South Africa
| |
Collapse
|
6
|
Wilson SA, Tank RKJ, Hobbs JK, Foster SJ, Garner EC. An exhaustive multiple knockout approach to understanding cell wall hydrolase function in Bacillus subtilis. mBio 2023; 14:e0176023. [PMID: 37768080 PMCID: PMC10653849 DOI: 10.1128/mbio.01760-23] [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: 07/12/2023] [Accepted: 08/03/2023] [Indexed: 09/29/2023] Open
Abstract
IMPORTANCE In order to grow, bacterial cells must both create and break down their cell wall. The enzymes that are responsible for these processes are the target of some of our best antibiotics. Our understanding of the proteins that break down the wall- cell wall hydrolases-has been limited by redundancy among the large number of hydrolases many bacteria contain. To solve this problem, we identified 42 cell wall hydrolases in Bacillus subtilis and created a strain lacking 40 of them. We show that cells can survive using only a single cell wall hydrolase; this means that to understand the growth of B. subtilis in standard laboratory conditions, it is only necessary to study a very limited number of proteins, simplifying the problem substantially. We additionally show that the ∆40 strain is a research tool to characterize hydrolases, using it to identify three "helper" hydrolases that act in certain stress conditions.
Collapse
Affiliation(s)
- Sean A. Wilson
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts, USA
- Center for Systems Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Raveen K. J. Tank
- Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom
| | - Jamie K. Hobbs
- Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom
| | - Simon J. Foster
- School of Biosciences, University of Sheffield, Sheffield, United Kingdom
| | - Ethan C. Garner
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts, USA
- Center for Systems Biology, Harvard University, Cambridge, Massachusetts, USA
| |
Collapse
|
7
|
Duan JL, Wu L, Zhang P, Ma JY, Sun XD, Liu XY, Geng FS, Liu MY, Sun YC, Cai C, Yan Z, Yuan XZ. In Situ Probing of the Intrinsic Adhesion Strength of Single Anaerobic Microbial Cells. Anal Chem 2023; 95:8325-8331. [PMID: 37191948 DOI: 10.1021/acs.analchem.3c00795] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Probing the single-cell mechanobiology in situ is imperative for microbial processes in the medical, industrial, and agricultural realms, but it remains a challenge. Herein, we present a single-cell force microscopy method that can be used to measure microbial adhesion strength under anaerobic conditions in situ. This method integrates atomic force microscopy with an anaerobic liquid cell and inverted fluorescence microscopy. We obtained the nanomechanical measurements of the single anaerobic bacterium Ethanoligenens harbinense YUAN-3 and the methanogenic archaeon Methanosarcina acetivorans C2A and their nanoscale adhesion forces in the presence of sulfoxaflor, a successor of neonicotinoid pesticides. This study presents a new tool for in situ single-cell force measurements of various anoxic and anaerobic species and provides new perspectives for evaluating the potential environmental risk of neonicotinoid applications in ecosystems.
Collapse
Affiliation(s)
- Jian-Lu Duan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Lei Wu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Ping Zhang
- Key Laboratory of Marine Drugs, Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266003, China
| | - Jing-Ya Ma
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Xiao-Dong Sun
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Xiao-Yu Liu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Fan-Shu Geng
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Mei-Yan Liu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Yu-Chen Sun
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Chao Cai
- Key Laboratory of Marine Drugs, Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266003, China
| | - Zhen Yan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
- Sino-French Research Institute for Ecology and Environment (ISFREE), Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Xian-Zheng Yuan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
- Sino-French Research Institute for Ecology and Environment (ISFREE), Shandong University, Qingdao, Shandong 266237, P. R. China
| |
Collapse
|
8
|
Pérez-Calvo E, Aureli R, Sorbara J, Cowieson A. Dietary muramidase increases ileal amino acid digestibility of wheat and corn-based broiler diets without affecting endogenous amino acid losses. Poult Sci 2023; 102:102619. [PMID: 37068354 PMCID: PMC10130490 DOI: 10.1016/j.psj.2023.102619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 02/24/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023] Open
Abstract
The objective of these studies was to evaluate the impact of dietary muramidase (MUR) on endogenous amino acids (AA) losses and digestibility of nutrients in wheat and corn-based broiler diets. In experiment 1, the effect of dietary MUR on the flow of endogenous AA (EAA) at the jejunum and terminal ileum of broilers were assessed using either the nitrogen (N) free diet method (NFD) or the highly digestible protein diet method (HDP; 100 g casein/kg diet). Sialic acid and muramic acid concentrations were measured in the jejunal content. In experiment 2, a 2x2x2 factorial arrangement of treatments with 2 base grains (wheat or corn), with low or high metabolizable energy (ME) levels, and without or with MUR supplementation was implemented. All diets contained phytase, xylanase, and cellulase. Apparent ileal digestibility (AID) of dry matter (DM), protein (CP), amino acids (AA), crude fat, and energy, as well as the apparent total tract metabolizability (ATTM) of DM, CP, and gross energy (GE) were determined. The standardized ileal digestibility (SID) of AA was obtained by correcting AID values for basal ileal EAA obtained from chicks fed with NFD or HDP in experiment 1, jejunal EAA flow of all AA was higher (P < 0.001) compared to the ileum, but this effect was method dependent. Jejunal, but not ileal, EAA flow measured with HDP was higher compared to NFD, as well as sialic acid (P < 0.001) and muramic acid (P < 0.004) concentrations. Muramidase inclusion had no effect on basal EAA flow, independently of the segment and the method used. In experiment 2, dietary MUR supplementation increased the AID of CP (P < 0.05), all AA, and tended (P = 0.07) to increase the AID of GE, independently of the cereal type used. However, ATTM of DM and GE, but not CP, increased with MUR inclusion compared with the control treatments, especially in wheat and low ME diets (P < 0.05). In conclusion, MUR supplementation improved AID of CP and AA without affecting EAA losses and increases energy utilization.
Collapse
|
9
|
Fischer MA, Engelgeh T, Rothe P, Fuchs S, Thürmer A, Halbedel S. Listeria monocytogenes genes supporting growth under standard laboratory cultivation conditions and during macrophage infection. Genome Res 2022; 32:1711-1726. [PMID: 36114002 PMCID: PMC9528990 DOI: 10.1101/gr.276747.122] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 08/04/2022] [Indexed: 11/24/2022]
Abstract
The Gram-positive bacterium Listeria monocytogenes occurs widespread in the environment and infects humans when ingested along with contaminated food. Such infections are particularly dangerous for risk group patients, for whom they represent a life-threatening disease. To invent novel strategies to control contamination and disease, it is important to identify those cellular processes that maintain pathogen growth inside and outside the host. Here, we have applied transposon insertion sequencing (Tn-Seq) to L. monocytogenes for the identification of such processes on a genome-wide scale. Our approach identified 394 open reading frames that are required for growth under standard laboratory conditions and 42 further genes, which become necessary during intracellular growth in macrophages. Most of these genes encode components of the translation machinery and act in chromosome-related processes, cell division, and biosynthesis of the cellular envelope. Several cofactor biosynthesis pathways and 29 genes with unknown functions are also required for growth, suggesting novel options for the development of antilisterial drugs. Among the genes specifically required during intracellular growth are known virulence factors, genes compensating intracellular auxotrophies, and several cell division genes. Our experiments also highlight the importance of PASTA kinase signaling for general viability and of glycine metabolism and chromosome segregation for efficient intracellular growth of L. monocytogenes.
Collapse
Affiliation(s)
- Martin A Fischer
- FG11 Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany
| | - Tim Engelgeh
- FG11 Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany
| | - Patricia Rothe
- FG11 Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany
| | - Stephan Fuchs
- MF1 Bioinformatic Support, Robert Koch Institute, 13353 Berlin, Germany
| | - Andrea Thürmer
- MF2 Genome Sequencing, Robert Koch Institute, 13353 Berlin, Germany
| | - Sven Halbedel
- FG11 Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany
| |
Collapse
|
10
|
Riu F, Ruda A, Ibba R, Sestito S, Lupinu I, Piras S, Widmalm G, Carta A. Antibiotics and Carbohydrate-Containing Drugs Targeting Bacterial Cell Envelopes: An Overview. Pharmaceuticals (Basel) 2022; 15:942. [PMID: 36015090 PMCID: PMC9414505 DOI: 10.3390/ph15080942] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/20/2022] [Accepted: 07/20/2022] [Indexed: 02/07/2023] Open
Abstract
Certain bacteria constitute a threat to humans due to their ability to escape host defenses as they easily develop drug resistance. Bacteria are classified into gram-positive and gram-negative according to the composition of the cell membrane structure. Gram-negative bacteria have an additional outer membrane (OM) that is not present in their gram-positive counterpart; the latter instead hold a thicker peptidoglycan (PG) layer. This review covers the main structural and functional properties of cell wall polysaccharides (CWPs) and PG. Drugs targeting CWPs are discussed, both noncarbohydrate-related (β-lactams, fosfomycin, and lipopeptides) and carbohydrate-related (glycopeptides and lipoglycopeptides). Bacterial resistance to these drugs continues to evolve, which calls for novel antibacterial approaches to be developed. The use of carbohydrate-based vaccines as a valid strategy to prevent bacterial infections is also addressed.
Collapse
Affiliation(s)
- Federico Riu
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Via Muroni 23/A, 07100 Sassari, Italy; (F.R.); (I.L.); (S.P.); (A.C.)
| | - Alessandro Ruda
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden; (A.R.); (G.W.)
| | - Roberta Ibba
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Via Muroni 23/A, 07100 Sassari, Italy; (F.R.); (I.L.); (S.P.); (A.C.)
| | - Simona Sestito
- Department of Chemical, Physical, Mathematical and Natural Sciences, University of Sassari, Via Vienna 2, 07100 Sassari, Italy;
| | - Ilenia Lupinu
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Via Muroni 23/A, 07100 Sassari, Italy; (F.R.); (I.L.); (S.P.); (A.C.)
| | - Sandra Piras
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Via Muroni 23/A, 07100 Sassari, Italy; (F.R.); (I.L.); (S.P.); (A.C.)
| | - Göran Widmalm
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden; (A.R.); (G.W.)
| | - Antonio Carta
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Via Muroni 23/A, 07100 Sassari, Italy; (F.R.); (I.L.); (S.P.); (A.C.)
| |
Collapse
|
11
|
Characterization of ampicillin-resistant genes in Vibrio parahaemolyticus. Microb Pathog 2022; 168:105573. [PMID: 35588966 DOI: 10.1016/j.micpath.2022.105573] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 04/28/2022] [Accepted: 05/07/2022] [Indexed: 12/29/2022]
Abstract
Vibrio parahaemolyticus is strongly resistant to ampicillin (AMP). In this study, AMP-resistant genes in V. parahaemolyticus ATCC33846 were characterized. Transcriptomic analysis of V. parahaemolyticus exposed to AMP revealed 4608 differentially transcribed genes, including 670 significantly up-regulated genes and 655 significantly down-regulated genes. Based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses, significantly modulated genes in ATCC33846 under AMP stimulation were observed in the following categories: microbial metabolism in diverse environments, metabolic pathways, bacterial secretion system, citrate cycle, biofilm formation, oxidative phosphorylation, ribosome, citrate cycle, pyruvate metabolism, carbon metabolism, nitrogen metabolism, fatty acid metabolism and tryptophan metabolism. The genes VPA0510, VPA0252, VPA0699, VPA0768, VPA0320, VP0636, VPA1096, VPA0947 and VP1775 were significantly up-regulated at the similar level to blaA in V. parahaemolyticus under AMP stimulation, and their overexpression in V. parahaemolyticus could increase its resistance to AMP. These results indicate that AMP has a global influence on V. parahaemolyticus cells. The findings would provide new insights into the resistant mechanism of V. parahaemolyticus to AMP, which would be helpful for developing novel drugs for treating V. parahaemolyticus infection.
Collapse
|
12
|
Heydari S, Malekzadeh R, Jazayeri MH, Sarrafnejad A, Siavoshi F. Detection of peptidoglycan in yeast as a marker for the presence or abundance of intracellular Helicobacter pylori and Staphylococcus. Arch Microbiol 2022; 204:407. [PMID: 35726098 DOI: 10.1007/s00203-022-03045-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 05/21/2022] [Accepted: 05/27/2022] [Indexed: 11/26/2022]
Abstract
Peptidoglycan (PG) was targeted as the marker for bacterial occurrence inside yeast. Detection of only few bacteria in old and new generations of yeast raised the question of how yeast controls the abundance of its intracellular bacteria. One gastric C. tropicalis that showed concurrence of H. pylori and Staphylococcus 16S rDNA was stained for assessing the viability of intracellular bacteria. Fluorescein isothiocyanate (FITC)-labeled anti-PG monoclonal antibody (APGMAb) was used for detection of PG inside yeast by direct immunofluorescence. APGMAb-coated magnetic beads were used for separation of bacteria from disrupted yeasts. Bead-bound bacteria were separated, fixed, stained, and examined by scanning electron microscope (SEM). Bead-bound bacteria were cultured and identified by amplification and sequencing of 16S rDNA. Fluorescence microscopy demonstrated occurrence of few live bacteria inside yeast cells. FITC- APGMAb interacted with PG of intracellular bacteria, appearing as few green spots in mother and daughter yeast cells. Interestingly, PG fragments were also detected in the exterior of yeast cells. SEM observations showed separated bead-bound bacilli and cocci. Culture of Staphylococcus was positive. Sequencing results confirmed identity of separated bacteria as H. pylori and Staphylococcus. PG detected inside yeast may have belonged to H. pylori, Staphylococcus or any other intracellular bacteria that coexisted in yeast as its microbiome. Detection of only few intracellular bacteria in old and new generations of yeast as well as PG fragments in their exterior suggested that yeast controls the abundance of its intracellular bacteria at low rate by hydrolysis and exporting of PG.
Collapse
Affiliation(s)
- Samira Heydari
- Department of Microbiology, School of Biology, University College of Sciences, University of Tehran, Tehran, Iran
| | - Reza Malekzadeh
- Digestive Disease Research Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Mir Hadi Jazayeri
- Immunology Research Center, Iran University of Medical Sciences, Tehran, Iran
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Abdolfattah Sarrafnejad
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Farideh Siavoshi
- Department of Microbiology, School of Biology, University College of Sciences, University of Tehran, Tehran, Iran.
| |
Collapse
|
13
|
Debasmita D, Ghosh SS, Chattopadhyay A. Hierarchical Passage of Gold Nanoclusters in Living Bacteria. ACS APPLIED BIO MATERIALS 2022; 5:2543-2548. [PMID: 35609302 DOI: 10.1021/acsabm.2c00315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gold (Au) nanoclusters chemically synthesized on the cell surface of living Lactobacillus rhamnosus rendered them photoluminescent. Importantly, the bacteria were viable and the clusters were passed down the generations with the loss of luminescence in the first subculture onward. The clusters were agglomerated into spherical structures of 100-200 nm, without being converted to plasmonic Au nanoparticles, on the cell surfaces of the bacteria of all six subcultures studied. The results indicated the role of cell wall remodeling in transforming the Au nanoclusters into larger aggregates down the generations. This may hold important implications for using nanoparticle-studded bacteria in theranostics.
Collapse
|
14
|
Wamp S, Rothe P, Stern D, Holland G, Döhling J, Halbedel S. MurA escape mutations uncouple peptidoglycan biosynthesis from PrkA signaling. PLoS Pathog 2022; 18:e1010406. [PMID: 35294506 PMCID: PMC8959180 DOI: 10.1371/journal.ppat.1010406] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 03/28/2022] [Accepted: 02/28/2022] [Indexed: 01/23/2023] Open
Abstract
Gram-positive bacteria are protected by a thick mesh of peptidoglycan (PG) completely engulfing their cells. This PG network is the main component of the bacterial cell wall, it provides rigidity and acts as foundation for the attachment of other surface molecules. Biosynthesis of PG consumes a high amount of cellular resources and therefore requires careful adjustments to environmental conditions. An important switch in the control of PG biosynthesis of Listeria monocytogenes, a Gram-positive pathogen with a high infection fatality rate, is the serine/threonine protein kinase PrkA. A key substrate of this kinase is the small cytosolic protein ReoM. We have shown previously that ReoM phosphorylation regulates PG formation through control of MurA stability. MurA catalyzes the first step in PG biosynthesis and the current model suggests that phosphorylated ReoM prevents MurA degradation by the ClpCP protease. In contrast, conditions leading to ReoM dephosphorylation stimulate MurA degradation. How ReoM controls degradation of MurA and potential other substrates is not understood. Also, the individual contribution of the ~20 other known PrkA targets to PG biosynthesis regulation is unknown. We here present murA mutants which escape proteolytic degradation. The release of MurA from ClpCP-dependent proteolysis was able to activate PG biosynthesis and further enhanced the intrinsic cephalosporin resistance of L. monocytogenes. This latter effect required the RodA3/PBP B3 transglycosylase/transpeptidase pair. One murA escape mutation not only fully rescued an otherwise non-viable prkA mutant during growth in batch culture and inside macrophages but also overcompensated cephalosporin hypersensitivity. Our data collectively indicate that the main purpose of PrkA-mediated signaling in L. monocytogenes is control of MurA stability during standard laboratory growth conditions and intracellular growth in macrophages. These findings have important implications for the understanding of PG biosynthesis regulation and β-lactam resistance of L. monocytogenes and related Gram-positive bacteria. Peptidoglycan (PG) is the main component of the bacterial cell wall and many of the PG synthesizing enzymes are antibiotic targets. We previously have discovered a new signaling route controlling PG production in the human pathogen Listeria monocytogenes. This route also determines the intrinsic resistance of L. monocytogenes against cephalosporins, a group of β-lactam antibiotics. Signaling involves PrkA, a membrane-embedded protein kinase, that is activated during cell wall stress to phosphorylate its target ReoM. Depending on its phosphorylation, ReoM activates or inactivates PG production by controlling the proteolytic stability of MurA, which catalyzes the first step in PG biosynthesis. MurA degradation depends on the ClpCP protease and we here have isolated murA mutations that escape this degradation. Using these mutants, we could show that regulation of PG biosynthesis through control of MurA stability is an important purpose of PrkA-mediated signaling in L. monocytogenes. Further experiments identified the transglycosylase RodA and the transpeptidase PBP B3 as additional downstream factors. Our results suggest that both proteins act together to translate the signals received by PrkA into adjustment of PG biosynthesis. These findings shed new light on the regulation of PG biosynthesis in Gram-positive bacteria with intrinsic β-lactam resistance.
Collapse
Affiliation(s)
- Sabrina Wamp
- FG11 - Division of Enteropathogenic bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
| | - Patricia Rothe
- FG11 - Division of Enteropathogenic bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
| | - Daniel Stern
- ZBS3 - Biological Toxins, Robert Koch Institute, Berlin, Germany
| | - Gudrun Holland
- ZBS4 - Advanced Light and Electron Microscopy, Robert Koch Institute, Berlin, Germany
| | - Janina Döhling
- FG11 - Division of Enteropathogenic bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
| | - Sven Halbedel
- FG11 - Division of Enteropathogenic bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
- * E-mail:
| |
Collapse
|
15
|
Discovery and Biotechnological Exploitation of Glycoside-Phosphorylases. Int J Mol Sci 2022; 23:ijms23063043. [PMID: 35328479 PMCID: PMC8950772 DOI: 10.3390/ijms23063043] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/01/2022] [Accepted: 03/03/2022] [Indexed: 02/04/2023] Open
Abstract
Among carbohydrate active enzymes, glycoside phosphorylases (GPs) are valuable catalysts for white biotechnologies, due to their exquisite capacity to efficiently re-modulate oligo- and poly-saccharides, without the need for costly activated sugars as substrates. The reversibility of the phosphorolysis reaction, indeed, makes them attractive tools for glycodiversification. However, discovery of new GP functions is hindered by the difficulty in identifying them in sequence databases, and, rather, relies on extensive and tedious biochemical characterization studies. Nevertheless, recent advances in automated tools have led to major improvements in GP mining, activity predictions, and functional screening. Implementation of GPs into innovative in vitro and in cellulo bioproduction strategies has also made substantial advances. Herein, we propose to discuss the latest developments in the strategies employed to efficiently discover GPs and make the best use of their exceptional catalytic properties for glycoside bioproduction.
Collapse
|
16
|
The Microstructure, Antibacterial and Antitumor Activities of Chitosan Oligosaccharides and Derivatives. Mar Drugs 2022; 20:md20010069. [PMID: 35049924 PMCID: PMC8781119 DOI: 10.3390/md20010069] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/06/2022] [Accepted: 01/10/2022] [Indexed: 02/07/2023] Open
Abstract
Chitosan obtained from abundant marine resources has been proven to have a variety of biological activities. However, due to its poor water solubility, chitosan application is limited, and the degradation products of chitosan oligosaccharides are better than chitosan regarding performance. Chitosan oligosaccharides have two kinds of active groups, amino and hydroxyl groups, which can form a variety of derivatives, and the properties of these derivatives can be further improved. In this review, the key structures of chitosan oligosaccharides and recent studies on chitosan oligosaccharide derivatives, including their synthesis methods, are described. Finally, the antimicrobial and antitumor applications of chitosan oligosaccharides and their derivatives are discussed.
Collapse
|
17
|
Yang J, Yang X, Liang R, Zhu L, Mao Y, Dong P, Hopkins DL, Luo X, Zhang Y. The response of bacterial communities to carbon dioxide in high-oxygen modified atmosphere packaged beef steaks during chilled storage. Food Res Int 2022; 151:110872. [PMID: 34980405 DOI: 10.1016/j.foodres.2021.110872] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 10/17/2021] [Accepted: 12/03/2021] [Indexed: 11/30/2022]
Abstract
The objective of this study was to establish the effect of CO2 on the bacterial community in beef steaks held under both high-oxygen modified atmosphere packaging (HiOx-MAP) types (CO2 treated MAP: 50% O2/40% CO2/10% N2; control MAP: 50% O2/50% N2). Steaks were stored at 2 °C for 20 days. Gas composition, meat color, pH values, total volatile basic nitrogen values, total viable counts (TVC) and microbial community dynamics were monitored. Compared to the control MAP, the high level of CO2 in the contrast MAP significantly delayed bacterial growth, resulting in a bright red color as well as extending the shelf-life to over 20 days. The microbial diversity decreased with prolonged storage in both MAP types, but it was more complex in high-CO2 treated MAP steaks. When TVC values approached the shelf-life threshold for the control MAP, Pseudomonas and Brochothrix were the predominant bacteria, while Pseudomonas and Serratia under the CO2 containing MAP were at a lower abundance than under the control MAP. The dominant Pseudomonas species causing spoilage in the control MAP steaks was P. fragi, and this species was inhibited significantly by CO2, followed by P. weihenstephanensis. Inversely, P. versuta instead of P. fragi became the dominant Pseudomonas species under the CO2 treated MAP. Overall, the application of CO2 in HiOx-MAP influenced microbiota succession, which played an important role in retaining beef quality.
Collapse
Affiliation(s)
- Jun Yang
- Lab of Beef Processing and Quality Control, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; National R&D Center for Beef Processing Technology, Tai'an, Shandong 271018, PR China
| | - Xiaoyin Yang
- Lab of Beef Processing and Quality Control, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; National R&D Center for Beef Processing Technology, Tai'an, Shandong 271018, PR China.
| | - Rongrong Liang
- Lab of Beef Processing and Quality Control, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; National R&D Center for Beef Processing Technology, Tai'an, Shandong 271018, PR China
| | - Lixian Zhu
- Lab of Beef Processing and Quality Control, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; National R&D Center for Beef Processing Technology, Tai'an, Shandong 271018, PR China
| | - Yanwei Mao
- Lab of Beef Processing and Quality Control, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; National R&D Center for Beef Processing Technology, Tai'an, Shandong 271018, PR China
| | - Pengcheng Dong
- Lab of Beef Processing and Quality Control, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; National R&D Center for Beef Processing Technology, Tai'an, Shandong 271018, PR China
| | - David L Hopkins
- Lab of Beef Processing and Quality Control, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; Centre for Red Meat and Sheep Development, NSW Department of Primary Industries, Cowra, NSW 2794, Australia
| | - Xin Luo
- Lab of Beef Processing and Quality Control, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; National R&D Center for Beef Processing Technology, Tai'an, Shandong 271018, PR China
| | - Yimin Zhang
- Lab of Beef Processing and Quality Control, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; National R&D Center for Beef Processing Technology, Tai'an, Shandong 271018, PR China.
| |
Collapse
|
18
|
Metabolism of Poly-β1,4- N-Acetylglucosamine Substrates and Importation of N-Acetylglucosamine and Glucosamine by Enterococcus faecalis. J Bacteriol 2021; 203:e0037121. [PMID: 34424034 DOI: 10.1128/jb.00371-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The ability of Enterococcus faecalis to use a variety of carbon sources enables colonization at various anatomic sites within a mammalian host. N-Acetylglucosamine (GlcNAc) is one of the most abundant natural sugars and provides bacteria with a source of carbon and nitrogen when metabolized. N-Acetylglucosamine is also a component of bacterial peptidoglycan, further highlighting the significance of N-acetylglucosamine utilization. In this study, we show that CcpA-regulated enzymes are required for growth on the poly-β1,4-linked GlcNAc substrate, chitopentaose (β1,4-linked GlcNAc5). We also show that EF0114 (EndoE) is required for growth on chitobiose (β1,4-linked GlcNAc2) and that the GH20 domain of EndoE is required for the conversion of GlcNAc2 to N-acetylglucosamine. GlcNAc is transported into the cell via two separate phosphotransferase system (PTS) complexes, either the PTS IICBA encoded by ef1516 (nagE) or the Mpt glucose/mannose permease complex (MptBACD). The Mpt PTS is also the primary glucosamine transporter. In order for N-acetylglucosamine to be utilized as a carbon source, phosphorylated N-acetylglucosamine (GlcNAc-6-P) must be deacetylated, and here, we show that this activity is mediated by EF1317 (an N-acetylglucosamine-6-phosphate deacetylase; NagA homolog), as a deletion of ef1317 is unable to grow on GlcNAc as the carbon source. Deamination of glucosamine to fructose-6-phosphate is required for entry into glycolysis, and we show that growth on glucosamine is dependent on EF0466 (a glucosamine-6-phosphate deaminase; NagB homolog). Collectively, our data highlight the chitinolytic machinery required for breaking down exogenous chitinous substrates, as well as the uptake and cytosolic enzymes needed for metabolizing N-acetylglucosamine. IMPORTANCE Enterococcus faecalis causes life-threatening health care-associated infections in part due to its intrinsic and acquired antibiotic resistance, its ability to form biofilms, and its nutrient versatility. Alternative nutrient acquisition systems are key factors that contribute to enterococcal colonization at biologically unique host anatomic sites. Although E. faecalis can metabolize an array of carbon sources, little is known of how this bacterium acquires these secondary nutrient sources in mammalian hosts. Our research identifies the glycosidase machinery required for degrading exogenous chitinous substrates into N-acetylglucosamine monomers for transport and metabolism of one of the most abundant naturally occurring sugars, N-acetylglucosamine. Disrupting the function of this N-acetylglucosamine acquisition pathway may lead to new treatments against multidrug-resistant enterococcal infections.
Collapse
|
19
|
Wysocka A, Jagielska E, Łężniak Ł, Sabała I. Two New M23 Peptidoglycan Hydrolases With Distinct Net Charge. Front Microbiol 2021; 12:719689. [PMID: 34630350 PMCID: PMC8498115 DOI: 10.3389/fmicb.2021.719689] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 08/16/2021] [Indexed: 11/13/2022] Open
Abstract
Bacterial peptidoglycan hydrolases play an essential role in cell wall metabolism during bacterial growth, division, and elongation (autolysins) or in the elimination of closely related species from the same ecological niche (bacteriocins). Most studies concerning the peptidoglycan hydrolases present in Gram-positive bacteria have focused on clinically relevant Staphylococcus aureus or the model organism Bacillus subtilis, while knowledge relating to other species remains limited. Here, we report two new peptidoglycan hydrolases from the M23 family of metallopeptidases derived from the same staphylococcal species, Staphylococcus pettenkoferi. They share modular architecture, significant sequence identity (60%), catalytic and binding residue conservation, and similar modes of activation, but differ in gene distribution, putative biological role, and, strikingly, in their isoelectric points (pIs). One of the peptides has a high pI, similar to that reported for all M23 peptidases evaluated to date, whereas the other displays a low pI, a unique feature among M23 peptidases. Consequently, we named them SpM23_B (Staphylococcus pettenkoferi M23 "Basic") and SpM23_A (Staphylococcus pettenkoferi M23 "Acidic"). Using genetic and biochemical approaches, we have characterized these two novel lytic enzymes, both in vitro and in their physiological context. Our study presents a detailed characterization of two novel and clearly distinct peptidoglycan hydrolases to understand their role in bacterial physiology.
Collapse
Affiliation(s)
- Alicja Wysocka
- International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Elżbieta Jagielska
- International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Łukasz Łężniak
- International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Izabela Sabała
- International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| |
Collapse
|
20
|
Chen D, Feng Q, Liang H. Effects of long-term discharge of acid mine drainage from abandoned coal mines on soil microorganisms: microbial community structure, interaction patterns, and metabolic functions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:53936-53952. [PMID: 34046832 DOI: 10.1007/s11356-021-14566-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 05/20/2021] [Indexed: 06/12/2023]
Abstract
More than twenty abandoned coal mines in the Yudong River Basin of Guizhou Province have discharged acid mine drainage (AMD) for a long time. The revelation of microbial community composition, interaction patterns, and metabolic functions can contribute to a better understanding of such ecosystems, which in its turn can be helpful in the development of strategies aiming at the ecological remediation of AMD pollution. In this study, reference and contaminated soil samples were collected along the AMD flow path for high-throughput sequencing. Results showed that the long-term AMD pollution promoted the evolution of γ-Proteobacteria, and the acidophilic iron-oxidizing bacteria Ferrovum (relative abundance of 15.50%) and iron-reducing bacteria Metallibacterium (9.87%) belonging to this class became the dominant genera. Co-occurrence analysis revealed that the proportion of positive correlations among bacteria increased from 51.02 (reference soil) to 75.16% (contaminated soil), suggesting that acidic pollution promotes the formation of mutualistic interaction networks of microorganisms. Metabolic function prediction (Tax4Fun) revealed that AMD contamination enhanced microbial functions such as translation, repair, and biosynthesis of peptidoglycan and lipopolysaccharide, etc., which may be an adaptive mechanism for microbial survival in extremely acidic environment. In addition, acidic pollution promoted the high expression of nitrogen-fixing genes in soil, and the discovery of autotrophic nitrogen-fixing bacteria such as Ferrovum highlights the possibility of using this taxon for bioremediation of AMD pollution.
Collapse
Affiliation(s)
- Di Chen
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, No. 1 Daxue Street, Quanshan District, Xuzhou, 221116, People's Republic of China.
| | - Qiyan Feng
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, No. 1 Daxue Street, Quanshan District, Xuzhou, 221116, People's Republic of China
| | - Haoqian Liang
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, No. 1 Daxue Street, Quanshan District, Xuzhou, 221116, People's Republic of China
| |
Collapse
|
21
|
Baggio G, Groves RA, Chignola R, Piacenza E, Presentato A, Lewis IA, Lampis S, Vallini G, Turner RJ. Untargeted Metabolomics Investigation on Selenite Reduction to Elemental Selenium by Bacillus mycoides SeITE01. Front Microbiol 2021; 12:711000. [PMID: 34603239 PMCID: PMC8481872 DOI: 10.3389/fmicb.2021.711000] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 08/16/2021] [Indexed: 12/02/2022] Open
Abstract
Bacillus mycoides SeITE01 is an environmental isolate that transforms the oxyanion selenite (SeO 3 2 - ) into the less bioavailable elemental selenium (Se0) forming biogenic selenium nanoparticles (Bio-SeNPs). In the present study, the reduction of sodium selenite (Na2SeO3) by SeITE01 strain and the effect ofSeO 3 2 - exposure on the bacterial cells was examined through untargeted metabolomics. A time-course approach was used to monitor both cell pellet and cell free spent medium (referred as intracellular and extracellular, respectively) metabolites in SeITE01 cells treated or not withSeO 3 2 - . The results show substantial biochemical changes in SeITE01 cells when exposed toSeO 3 2 - . The initial uptake ofSeO 3 2 - by SeITE01 cells (3h after inoculation) shows both an increase in intracellular levels of 4-hydroxybenzoate and indole-3-acetic acid, and an extracellular accumulation of guanosine, which are metabolites involved in general stress response adapting strategies. Proactive and defensive mechanisms againstSeO 3 2 - are observed between the end of lag (12h) and beginning of exponential (18h) phases. Glutathione and N-acetyl-L-cysteine are thiol compounds that would be mainly involved in Painter-type reaction for the reduction and detoxification ofSeO 3 2 - to Se0. In these growth stages, thiol metabolites perform a dual role, both acting against the toxic and harmful presence of the oxyanion and as substrate or reducing sources to scavenge ROS production. Moreover, detection of the amino acids L-threonine and ornithine suggests changes in membrane lipids. Starting from stationary phase (24 and 48h), metabolites related to the formation and release of SeNPs in the extracellular environment begin to be observed. 5-hydroxyindole acetate, D-[+]-glucosamine, 4-methyl-2-oxo pentanoic acid, and ethanolamine phosphate may represent signaling strategies following SeNPs release from the cytoplasmic compartment, with consequent damage to SeITE01 cell membranes. This is also accompanied by intracellular accumulation of trans-4-hydroxyproline and L-proline, which likely represent osmoprotectant activity. The identification of these metabolites suggests the activation of signaling strategies that would protect the bacterial cells fromSeO 3 2 - toxicity while it is converting into SeNPs.
Collapse
Affiliation(s)
- Greta Baggio
- Department of Biotechnology, University of Verona, Verona, Italy
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Ryan A. Groves
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Roberto Chignola
- Department of Biotechnology, University of Verona, Verona, Italy
| | - Elena Piacenza
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Alessandro Presentato
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Ian A. Lewis
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Silvia Lampis
- Department of Biotechnology, University of Verona, Verona, Italy
| | - Giovanni Vallini
- Department of Biotechnology, University of Verona, Verona, Italy
| | - Raymond J. Turner
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
22
|
Complement C5 inhibition protects against hemolytic anemia and acute kidney injury in anthrax peptidoglycan-induced sepsis in baboons. Proc Natl Acad Sci U S A 2021; 118:2104347118. [PMID: 34507997 DOI: 10.1073/pnas.2104347118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/14/2021] [Indexed: 01/20/2023] Open
Abstract
Late-stage anthrax infections are characterized by dysregulated immune responses and hematogenous spread of Bacillus anthracis, leading to extreme bacteremia, sepsis, multiple organ failure, and, ultimately, death. Despite the bacterium being nonhemolytic, some fulminant anthrax patients develop a secondary atypical hemolytic uremic syndrome (aHUS) through unknown mechanisms. We recapitulated the pathology in baboons challenged with cell wall peptidoglycan (PGN), a polymeric, pathogen-associated molecular pattern responsible for the hemostatic dysregulation in anthrax sepsis. Similar to aHUS anthrax patients, PGN induces an initial hematocrit elevation followed by progressive hemolytic anemia and associated renal failure. Etiologically, PGN induces erythrolysis through direct excessive activation of all three complement pathways. Blunting terminal complement activation with a C5 neutralizing peptide prevented the progressive deposition of membrane attack complexes on red blood cells (RBC) and subsequent intravascular hemolysis, heme cytotoxicity, and acute kidney injury. Importantly, C5 neutralization did not prevent immune recognition of PGN and shifted the systemic inflammatory responses, consistent with improved survival in sepsis. Whereas PGN-induced hemostatic dysregulation was unchanged, C5 inhibition augmented fibrinolysis and improved the thromboischemic resolution. Overall, our study identifies PGN-driven complement activation as the pathologic mechanism underlying hemolytic anemia in anthrax and likely other gram-positive infections in which PGN is abundantly represented. Neutralization of terminal complement reactions reduces the hemolytic uremic pathology induced by PGN and could alleviate heme cytotoxicity and its associated kidney failure in gram-positive infections.
Collapse
|
23
|
Frederiksen CØ, Cohn MT, Skov LK, Schmidt EGW, Schnorr KM, Buskov S, Leppänen M, Maasilta I, Perez-Calvo E, Lopez-Ulibarri R, Klausen M. A muramidase from Acremonium alcalophilum hydrolyse peptidoglycan found in the gastrointestinal tract of broiler chickens. J Ind Microbiol Biotechnol 2021; 48:6128676. [PMID: 33693885 PMCID: PMC9113140 DOI: 10.1093/jimb/kuab008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 01/20/2021] [Indexed: 12/19/2022]
Abstract
This study evaluates peptidoglycan hydrolysis by a microbial muramidase from the
fungus Acremonium alcalophilum in vitro and in the
gastrointestinal tract of broiler chickens. Peptidoglycan used for in
vitro studies was derived from 5 gram-positive chicken gut isolate
type strains. In vitro peptidoglycan hydrolysis was studied by
three approaches: (a) helium ion microscopy to identify visual phenotypes of
hydrolysis, (b) reducing end assay to quantify solubilization of peptidoglycan
fragments, and (c) mass spectroscopy to estimate relative abundances of soluble
substrates and reaction products. Visual effects of peptidoglycan hydrolysis
could be observed by helium ion microscopy and the increase in abundance of
soluble peptidoglycan due to hydrolysis was quantified by a reducing end assay.
Mass spectroscopy confirmed the release of hydrolysis products and identified
muropeptides from the five different peptidoglycan sources. Peptidoglycan
hydrolysis in chicken crop, jejunum, and caecum samples was measured by
quantifying the total and soluble muramic acid content. A significant increase
in the proportion of the soluble muramic acid was observed in all three segments
upon inclusion of the microbial muramidase in the diet.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Miika Leppänen
- Department of Biological and Environmental Sciences and Department of Physics, University of Jyvaskyla, Jyvaskyla, FI-40014, Finland
| | - Ilari Maasilta
- Department of Physics, University of Jyvaskyla, Jyvaskyla, FI-40014, Finland
| | - Estefania Perez-Calvo
- Research Centre for Animal Nutrition and Health, DSM Nutritional Products, Village-Neuf, F-68305 Saint Louis, France
| | | | | |
Collapse
|
24
|
Mitchell SJ, Verma D, Griswold KE, Bailey-Kellogg C. Building blocks and blueprints for bacterial autolysins. PLoS Comput Biol 2021; 17:e1008889. [PMID: 33793553 PMCID: PMC8051824 DOI: 10.1371/journal.pcbi.1008889] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 04/16/2021] [Accepted: 03/17/2021] [Indexed: 01/31/2023] Open
Abstract
Bacteria utilize a wide variety of endogenous cell wall hydrolases, or autolysins, to remodel their cell walls during processes including cell division, biofilm formation, and programmed death. We here systematically investigate the composition of these enzymes in order to gain insights into their associated biological processes, potential ways to disrupt them via chemotherapeutics, and strategies by which they might be leveraged as recombinant antibacterial biotherapies. To do so, we developed LEDGOs (lytic enzyme domains grouped by organism), a pipeline to create and analyze databases of autolytic enzyme sequences, constituent domain annotations, and architectural patterns of multi-domain enzymes that integrate peptidoglycan binding and degrading functions. We applied LEDGOs to eight pathogenic bacteria, gram negatives Acinetobacter baumannii, Klebsiella pneumoniae, Neisseria gonorrhoeae, and Pseudomonas aeruginosa; and gram positives Clostridioides difficile, Enterococcus faecium, Staphylococcus aureus, and Streptococcus pneumoniae. Our analysis of the autolytic enzyme repertoires of these pathogens reveals commonalities and differences in their key domain building blocks and architectures, including correlations and preferred orders among domains in multi-domain enzymes, repetitions of homologous binding domains with potentially complementarity recognition modalities, and sequence similarity patterns indicative of potential divergence of functional specificity among related domains. We have further identified a variety of unannotated sequence regions within the lytic enzymes that may themselves contain new domains with important functions.
Collapse
Affiliation(s)
- Spencer J. Mitchell
- Department of Computer Science, Dartmouth, Hanover, New Hampshire, United States of America
| | - Deeptak Verma
- Computational and Structural Chemistry, Merck & Co., Inc., Kenilworth, New Jersey, United States of America
| | - Karl E. Griswold
- Thayer School of Engineering, Dartmouth, Hanover, New Hampshire, United States of America
- Lyticon LLC, Lebanon, New Hampshire, United States of America
| | - Chris Bailey-Kellogg
- Department of Computer Science, Dartmouth, Hanover, New Hampshire, United States of America
- Lyticon LLC, Lebanon, New Hampshire, United States of America
- * E-mail:
| |
Collapse
|
25
|
Current knowledge and recent advances in understanding metabolism of the model cyanobacterium Synechocystis sp. PCC 6803. Biosci Rep 2021; 40:222317. [PMID: 32149336 PMCID: PMC7133116 DOI: 10.1042/bsr20193325] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 02/06/2023] Open
Abstract
Cyanobacteria are key organisms in the global ecosystem, useful models for studying metabolic and physiological processes conserved in photosynthetic organisms, and potential renewable platforms for production of chemicals. Characterizing cyanobacterial metabolism and physiology is key to understanding their role in the environment and unlocking their potential for biotechnology applications. Many aspects of cyanobacterial biology differ from heterotrophic bacteria. For example, most cyanobacteria incorporate a series of internal thylakoid membranes where both oxygenic photosynthesis and respiration occur, while CO2 fixation takes place in specialized compartments termed carboxysomes. In this review, we provide a comprehensive summary of our knowledge on cyanobacterial physiology and the pathways in Synechocystis sp. PCC 6803 (Synechocystis) involved in biosynthesis of sugar-based metabolites, amino acids, nucleotides, lipids, cofactors, vitamins, isoprenoids, pigments and cell wall components, in addition to the proteins involved in metabolite transport. While some pathways are conserved between model cyanobacteria, such as Synechocystis, and model heterotrophic bacteria like Escherichia coli, many enzymes and/or pathways involved in the biosynthesis of key metabolites in cyanobacteria have not been completely characterized. These include pathways required for biosynthesis of chorismate and membrane lipids, nucleotides, several amino acids, vitamins and cofactors, and isoprenoids such as plastoquinone, carotenoids, and tocopherols. Moreover, our understanding of photorespiration, lipopolysaccharide assembly and transport, and degradation of lipids, sucrose, most vitamins and amino acids, and haem, is incomplete. We discuss tools that may aid our understanding of cyanobacterial metabolism, notably CyanoSource, a barcoded library of targeted Synechocystis mutants, which will significantly accelerate characterization of individual proteins.
Collapse
|
26
|
Characterization of antibacterial activity of a N-acetylmuramoyl-L-alanine amidase produced by Latilactobacillus sakei isolated from salami. World J Microbiol Biotechnol 2021; 37:65. [PMID: 33740141 DOI: 10.1007/s11274-021-03033-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 03/08/2021] [Indexed: 12/16/2022]
Abstract
Lactic acid bacteria are the predominant group within meat products, whose metabolites such as bacteriocins and peptidoglycan hydrolases inhibit pathogenic or spoilage bacteria. Fermented meat products, as a salami, is a good source to analyze the viable microbiota, due to these products present a low risk to consumer health. The aim of this work was to identify the lactic acid bacteria with broad antibacterial activity present in salami, purify the protein responsible for this activity, achieve antagonistic spectrum and perform the biochemical characterization. Five strains from salami were selected, isolated and identified by 16S rRNA gene sequencing. The antimicrobial activity was evaluated by antagonism assay and zymography, using spoilage microorganisms commonly found in meat products. The strain that showed a broad antibacterial activity was Latilactobacillus sakei and the antibacterial activity was given by a protein with 75-kDa of molecular mass, identified by LC/MALDI-TOF/TOF. The sequence analysis showed 67% of identity with a N-acetylmuramoyl-L-alanine amidase protein with five non-identical LysM domains. The purified protein showed an optimal pH of 8.0 and heat resistance at 80 °C for 10 min. L. sakei strain displayed antibacterial activity against Gram-negative and Gram-positive spoilage microorganisms. The results of this study provide the information to use Latilactobacillus sakei as a starter culture which will provide the necessary metabolites to combat undesirable microorganisms. Additionally, the conditions and properties for the best application and use of the antibacterial protein produced by this strain. This protein may have a potential use in the food industry as a new antibacterial agent.
Collapse
|
27
|
Zhang Y, Huang HH, Duc HM, Masuda Y, Honjoh KI, Miyamoto T. Endolysin LysSTG2: Characterization and application to control Salmonella Typhimurium biofilm alone and in combination with slightly acidic hypochlorous water. Food Microbiol 2021; 98:103791. [PMID: 33875220 DOI: 10.1016/j.fm.2021.103791] [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: 01/13/2021] [Revised: 03/15/2021] [Accepted: 03/15/2021] [Indexed: 01/12/2023]
Abstract
The gene encoding LysSTG2, an endolysin from Salmonella-lytic bacteriophage STG2, was cloned, overexpressed, and characterized. LysSTG2 consists of a single domain belonging to the Peptidase_M15 superfamily. LysSTG2 showed strong lytic activity against chloroform-treated S. Typhimurium cells after incubation at 4-50 °C for 30 min, at pH ranging from 7.0 to 11.0, and in the presence of NaCl from 0 to 300 mmol/L. It also showed lytic activity against all the 14 tested Gram-negative strains treated with chloroform, including Salmonella, E. coli, and Pseudomonas aeruginosa, but not against the Gram-positive bacteria tested. In addition, LysSTG2 (100 μg/mL) reduced the viability of S. Typhimurium NBRC 12529 planktonic cells by 1.2 log and that of the biofilm cells after 1-h treatment. Sequential treatment of slightly acidic hypochlorous water (SAHW) containing 40 mg/L available chlorine and LysSTG2 (100 μg/mL) was effective on S. Typhimurium NBRC 12529 biofilm cells, removing more than 99% of biofilm cells. These results demonstrate that LysSTG2 alone can effectively kill S. Typhimurium cells after permeabilization treatment and successfully control S. Typhimurium in biofilms in combination with SAHW, suggesting that the combined use of LysSTG2 and SAHW might be a novel and promising method for combating S. Typhimurium in food industries.
Collapse
Affiliation(s)
- Yu Zhang
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Hung-Hsin Huang
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Hoang Minh Duc
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Viet Nam
| | - Yoshimitsu Masuda
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Ken-Ichi Honjoh
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Takahisa Miyamoto
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
| |
Collapse
|
28
|
Jiménez-Bonilla P, Feng J, Wang S, Zhang J, Wang Y, Blersch D, de-Bashan LE, Gaillard P, Guo L, Wang Y. Identification and Investigation of Autolysin Genes in Clostridium saccharoperbutylacetonicum Strain N1-4 for Enhanced Biobutanol Production. Appl Environ Microbiol 2021; 87:e02442-20. [PMID: 33514516 PMCID: PMC8091608 DOI: 10.1128/aem.02442-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/14/2021] [Indexed: 11/20/2022] Open
Abstract
Biobutanol is a valuable biochemical and one of the most promising biofuels. Clostridium saccharoperbutylacetonicum N1-4 is a hyperbutanol-producing strain. However, its strong autolytic behavior leads to poor cell stability, especially during continuous fermentation, thus limiting the applicability of the strain for long-term and industrial-scale processes. In this study, we aimed to evaluate the role of autolysin genes within the C. saccharoperbutylacetonicum genome related to cell autolysis and further develop more stable strains for enhanced butanol production. First, putative autolysin-encoding genes were identified in the strain based on comparison of amino acid sequence with homologous genes in other strains. Then, by overexpressing all these putative autolysin genes individually and characterizing the corresponding recombinant strains, four key genes were pinpointed to be responsible for significant cell autolysis activities. Further, these key genes were deleted using CRISPR-Cas9. Fermentation characterization demonstrated enhanced performance of the resultant mutants. Results from this study reveal valuable insights concerning the role of autolysins for cell stability and solvent production, and they provide an essential reference for developing robust strains for enhanced biofuel and biochemical production.IMPORTANCE Severe autolytic behavior is a common issue in Clostridium and many other microorganisms. This study revealed the key genes responsible for the cell autolysis within Clostridium saccharoperbutylacetonicum, a prominent platform for biosolvent production from lignocellulosic materials. The knowledge generated in this study provides insights concerning cell autolysis in relevant microbial systems and gives essential references for enhancing strain stability through rational genome engineering.
Collapse
Affiliation(s)
- Pablo Jiménez-Bonilla
- Department of Biosystems Engineering, Auburn University, Auburn, Alabama, USA
- School of Chemistry, National University (UNA), Heredia, Costa Rica
| | - Jun Feng
- Department of Biosystems Engineering, Auburn University, Auburn, Alabama, USA
| | - Shangjun Wang
- Department of Biosystems Engineering, Auburn University, Auburn, Alabama, USA
| | - Jie Zhang
- Department of Biosystems Engineering, Auburn University, Auburn, Alabama, USA
| | - Yifen Wang
- Department of Biosystems Engineering, Auburn University, Auburn, Alabama, USA
- Center for Bioenergy and Bioproducts, Auburn University, Auburn, Alabama, USA
| | - David Blersch
- Department of Biosystems Engineering, Auburn University, Auburn, Alabama, USA
| | - Luz Estela de-Bashan
- Environmental Microbiology Group, Northwestern Center for Biological Research (CIBNOR), La Paz, Mexico
- The Bashan Institute of Science, Auburn, Alabama, USA
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Philippe Gaillard
- Statistical Consulting Center, Mathematics and Statistics Department, Auburn University, Auburn, Alabama, USA
| | - Liang Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, China
| | - Yi Wang
- Department of Biosystems Engineering, Auburn University, Auburn, Alabama, USA
- Center for Bioenergy and Bioproducts, Auburn University, Auburn, Alabama, USA
| |
Collapse
|
29
|
Müller M, Calvert M, Hottmann I, Kluj RM, Teufel T, Balbuchta K, Engelbrecht A, Selim KA, Xu Q, Borisova M, Titz A, Mayer C. The exo-β-N-acetylmuramidase NamZ from Bacillus subtilis is the founding member of a family of exo-lytic peptidoglycan hexosaminidases. J Biol Chem 2021; 296:100519. [PMID: 33684445 PMCID: PMC8054146 DOI: 10.1016/j.jbc.2021.100519] [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: 01/07/2021] [Revised: 02/27/2021] [Accepted: 03/04/2021] [Indexed: 11/11/2022] Open
Abstract
Endo-β-N-acetylmuramidases, commonly known as lysozymes, are well-characterized antimicrobial enzymes that catalyze an endo-lytic cleavage of peptidoglycan; i.e., they hydrolyze the β-1,4-glycosidic bonds connecting N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc). In contrast, little is known about exo-β-N-acetylmuramidases, which catalyze an exo-lytic cleavage of β-1,4-MurNAc entities from the non-reducing ends of peptidoglycan chains. Such an enzyme was identified earlier in the bacterium Bacillus subtilis, but the corresponding gene has remained unknown so far. We now report that ybbC of B. subtilis, renamed namZ, encodes the reported exo-β-N-acetylmuramidase. A ΔnamZ mutant accumulated specific cell wall fragments and showed growth defects under starvation conditions, indicating a role of NamZ in cell wall turnover and recycling. Recombinant NamZ protein specifically hydrolyzed the artificial substrate para-nitrophenyl β-MurNAc and the peptidoglycan-derived disaccharide MurNAc-β-1,4-GlcNAc. Together with the exo-β-N-acetylglucosaminidase NagZ and the exo-muramoyl-l-alanine amidase AmiE, NamZ degraded intact peptidoglycan by sequential hydrolysis from the non-reducing ends. A structure model of NamZ, built on the basis of two crystal structures of putative orthologs from Bacteroides fragilis, revealed a two-domain structure including a Rossmann-fold-like domain that constitutes a unique glycosidase fold. Thus, NamZ, a member of the DUF1343 protein family of unknown function, is now classified as the founding member of a new family of glycosidases (CAZy GH171; www.cazy.org/GH171.html). NamZ-like peptidoglycan hexosaminidases are mainly present in the phylum Bacteroidetes and less frequently found in individual genomes within Firmicutes (Bacilli, Clostridia), Actinobacteria, and γ-proteobacteria.
Collapse
Affiliation(s)
- Maraike Müller
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Matthew Calvert
- Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarbrücken, Germany; Deutsches Zentrum für Infektionsforschung (DZIF), Standort Hannover-Braunschweig, Germany; Department of Chemistry, Saarland University, Saarbrücken, Germany
| | - Isabel Hottmann
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Robert Maria Kluj
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Tim Teufel
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Katja Balbuchta
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Alicia Engelbrecht
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Khaled A Selim
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany; Chemistry of Natural and Microbial Products Department, Pharmaceutical and Drug Industries Research Division, National Research Center, Giza, Egypt
| | - Qingping Xu
- GM/CA @ APS, Argonne National Laboratory, Lemont, Illinois, USA
| | - Marina Borisova
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Alexander Titz
- Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarbrücken, Germany; Deutsches Zentrum für Infektionsforschung (DZIF), Standort Hannover-Braunschweig, Germany; Department of Chemistry, Saarland University, Saarbrücken, Germany
| | - Christoph Mayer
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany.
| |
Collapse
|
30
|
A synthetic 5,3-cross-link in the cell wall of rod-shaped Gram-positive bacteria. Proc Natl Acad Sci U S A 2021; 118:2100137118. [PMID: 33836615 DOI: 10.1073/pnas.2100137118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Gram-positive bacteria assemble a multilayered cell wall that provides tensile strength to the cell. The cell wall is composed of glycan strands cross-linked by nonribosomally synthesized peptide stems. Herein, we modify the peptide stems of the Gram-positive bacterium Bacillus subtilis with noncanonical electrophilic d-amino acids, which when in proximity to adjacent stem peptides form novel covalent 5,3-cross-links. Approximately 20% of canonical cell-wall cross-links can be replaced with synthetic cross-links. While a low level of synthetic cross-link formation does not affect B. subtilis growth and phenotype, at higher levels cell growth is perturbed and bacteria elongate. A comparison of the accumulation of synthetic cross-links over time in Gram-negative and Gram-positive bacteria highlights key differences between them. The ability to perturb cell-wall architecture with synthetic building blocks provides a novel approach to studying the adaptability, elasticity, and porosity of bacterial cell walls.
Collapse
|
31
|
Sachla AJ, Helmann JD. Resource sharing between central metabolism and cell envelope synthesis. Curr Opin Microbiol 2021; 60:34-43. [PMID: 33581378 DOI: 10.1016/j.mib.2021.01.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 01/18/2021] [Accepted: 01/27/2021] [Indexed: 12/14/2022]
Abstract
Synthesis of the bacterial cell envelope requires a regulated partitioning of resources from central metabolism. Here, we consider the key metabolic junctions that provide the precursors needed to assemble the cell envelope. Peptidoglycan synthesis requires redirection of a glycolytic intermediate, fructose-6-phosphate, into aminosugar biosynthesis by the highly regulated branchpoint enzyme GlmS. MurA directs the downstream product, UDP-GlcNAc, specifically into peptidoglycan synthesis. Other shared resources required for cell envelope synthesis include the isoprenoid carrier lipid undecaprenyl phosphate and amino acids required for peptidoglycan cross-bridges. Assembly of the envelope requires a sharing of limited resources between competing cellular pathways and may additionally benefit from scavenging of metabolites released from neighboring cells or the formation of symbiotic relationships with a host.
Collapse
Affiliation(s)
- Ankita J Sachla
- Department of Microbiology, Cornell University, 370 Wing Hall, Wing Drive, Ithaca, NY 14853-8101, USA
| | - John D Helmann
- Department of Microbiology, Cornell University, 370 Wing Hall, Wing Drive, Ithaca, NY 14853-8101, USA.
| |
Collapse
|
32
|
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
|
33
|
Dietary muramidase degrades bacterial peptidoglycan to NOD-activating muramyl dipeptides and reduces duodenal inflammation in broiler chickens. Br J Nutr 2020; 126:641-651. [PMID: 33172510 DOI: 10.1017/s0007114520004493] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Muramidases constitute a superfamily of enzymes that hydrolyse peptidoglycan (PGN) from bacterial cell walls. Recently, a fungal muramidase derived from Acremonium alcalophilum has been shown to increase broiler performance when added as a feed additive. However, the underlying mechanisms of action are not yet identified. Here, we investigated the hypothesis that this muramidase can cleave PGN to muramyl dipeptide (MDP), activating nucleotide-binding oligomerisation domain-containing protein 2 (NOD2) receptors in eukaryotic cells, potentially inducing anti-inflammatory host responses. Using Micrococcus luteus as a test bacterium, it was shown that muramidase from A. alcalophilum did not display antimicrobial activity, while it could cleave fluorescently labelled PGN. It was shown that the muramidase could degrade PGN down to its minimal bioactive structure MDP by using UPLC-MS/MS. Using HEK-Blue™-hNOD2 reporter cells, it was shown that the muramidase-treated PGN degradation mixture could activate NOD2. Muramidase supplementation to broiler feed increased the duodenal goblet cell and intraepithelial lymphocyte abundance while reducing duodenal wall CD3+ T lymphocyte levels. Muramidase supplementation to broiler feed only had moderate effects on the duodenal, ileal and caecal microbiome. It was shown that the newly discovered muramidase hydrolysed PGN, resulting in MDP that activates NOD2, potentially steering the host response for improved intestinal health.
Collapse
|
34
|
Yang X, Zeng J, Zhou Q, Yu X, Zhong Y, Wang F, Du H, Nie F, Pang X, Wang D, Fan Y, Bai T, Xu Y. Elevating NagZ Improves Resistance to β-Lactam Antibiotics via Promoting AmpC β-Lactamase in Enterobacter cloacae. Front Microbiol 2020; 11:586729. [PMID: 33250874 PMCID: PMC7672007 DOI: 10.3389/fmicb.2020.586729] [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: 07/23/2020] [Accepted: 10/02/2020] [Indexed: 11/13/2022] Open
Abstract
Enterobacter cloacae complex (ECC), one of the most common opportunistic pathogens causing multiple infections in human, is resistant to β-lactam antibiotics mainly due to its highly expressed chromosomal AmpC β-lactamase. It seems that regulation of chromosomal AmpC β-lactamase is associated with peptidoglycan recycling. However, underlying mechanisms are still poorly understood. In this study, we confirmed that NagZ, a glycoside hydrolase participating in peptidoglycan recycling in Gram-negative bacteria, plays a crucial role in developing resistance of E. cloacae (EC) to β-lactam antibiotics by promoting expression of chromosomal AmpC β-lactamase. Our data shows that NagZ was significantly up-regulated in resistant EC (resistant to at least one type of the third or fourth generation cephalosporins) compared to susceptible EC (susceptible to all types of the third and fourth generation cephalosporins). Similarly, the expression and β-lactamase activity of ampC were markedly enhanced in resistant EC. Moreover, ectopic expression of nagZ enhanced ampC expression and resistance to β-lactam antibiotics in susceptible EC. To further understand functions of NagZ in β-lactam resistance, nagZ-knockout EC model (ΔnagZ EC) was constructed by homologous recombination. Conversely, ampC mRNA and protein levels were down-regulated, and resistance to β-lactam antibiotics was attenuated in ΔnagZ EC, while specific complementation of nagZ was able to rescue ampC expression and resistance in ΔnagZ EC. More interestingly, NagZ and its hydrolyzates 1,6-anhydromuropeptides (anhMurNAc) could induce the expression of other target genes of AmpR (a global transcriptional factor), which suggested that the promotion of AmpC by NagZ is mediated AmpR activated by anhMurNAc in EC. In conclusion, these findings provide new elements for a better understanding of resistance in EC, which is crucial for the identification of novel potential drug targets.
Collapse
Affiliation(s)
- Xianggui Yang
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Jun Zeng
- Division of Pulmonary and Critical Care Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Qin Zhou
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Xuejing Yu
- Department of Cardiothoracic Surgery, University of Utah, Salt Lake City, UT, United States
| | - Yuanxiu Zhong
- Department of Biotechnology, Chengdu Medical College, Chengdu, China
| | - Fuying Wang
- Department of Cardiothoracic Surgery, University of Utah, Salt Lake City, UT, United States
| | - Hongfei Du
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Fang Nie
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Xueli Pang
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Dan Wang
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Yingzi Fan
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Tingting Bai
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Ying Xu
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| |
Collapse
|
35
|
Lebas M, Garault P, Carrillo D, Codoñer FM, Derrien M. Metabolic Response of Faecalibacterium prausnitzii to Cell-Free Supernatants from Lactic Acid Bacteria. Microorganisms 2020; 8:microorganisms8101528. [PMID: 33027936 PMCID: PMC7650636 DOI: 10.3390/microorganisms8101528] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/28/2020] [Accepted: 09/30/2020] [Indexed: 01/16/2023] Open
Abstract
Interest in preventive or therapeutic strategies targeting gut microbiota is increasing. Such strategies may involve the direct replenishment of the gut microbiota with single strains or strain mixtures, or the manipulation of strain abundance through dietary intervention, including lactic acid bacteria. A few candidate species associated with health benefits have been identified, including Faecalibacterium prausnitzii. Given its growth requirements, modulation of this bacterium has not been extensively studied. In this investigation, we explored the capacity of cell-free supernatants of different Lactobacillus, Streptococcus, Lactococcus, and Bifidobacterium strains to stimulate the growth of F. prausnitzii A2-165. Modulation by four strains with the greatest capacity to stimulate growth or delay lysis, Lactococcus lactis subsp. lactis CNCM I-1631, Lactococcus lactis subsp. cremoris CNCM I-3558, Lactobacillus paracasei CNCM I-3689, and Streptococcus thermophilus CNCM I-3862, was further characterized by transcriptomics. The response of F. prausnitzii to cell-free supernatants from these four strains revealed several shared characteristics, in particular, upregulation of carbohydrate metabolism and cell wall-related genes and downregulation of replication and mobilome genes. Overall, this study suggests differential responses of F. prausnitzii to metabolites produced by different strains, providing protection against cell death, with an increase in peptidoglycan levels for cell wall formation, and reduced cell mobilome activity.
Collapse
Affiliation(s)
- Mathilde Lebas
- Danone Nutricia Research, RD 128 Avenue de la Vauve, 91767 Palaiseau Cédex, France; (M.L.); (P.G.)
| | - Peggy Garault
- Danone Nutricia Research, RD 128 Avenue de la Vauve, 91767 Palaiseau Cédex, France; (M.L.); (P.G.)
| | - Daniel Carrillo
- Archer Daniels Midland Co-Biopolis ADM Nutrition, C/Catedratico Agustin Escardino num 9 Edif 2, Paterna, 46980 Valencia, Spain;
| | - Francisco M. Codoñer
- Archer Daniels Midland Co-Biopolis ADM Nutrition, C/Catedratico Agustin Escardino num 9 Edif 2, Paterna, 46980 Valencia, Spain;
- Present Address: Danone Nutricia Research, 30th Biopolis Street Matrix Building, Singapore 138671, Singapore
- Correspondence: (F.M.C.); (M.D.)
| | - Muriel Derrien
- Danone Nutricia Research, RD 128 Avenue de la Vauve, 91767 Palaiseau Cédex, France; (M.L.); (P.G.)
- Correspondence: (F.M.C.); (M.D.)
| |
Collapse
|
36
|
Pirgozliev V, Simic A, Rose SP, Pérez Calvo E. Dietary microbial muramidase improves feed efficiency, energy and nutrient availability and welfare of broilers fed commercial type diets containing exogenous enzymes. Br Poult Sci 2020; 62:131-137. [PMID: 32875828 DOI: 10.1080/00071668.2020.1817330] [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] [Indexed: 10/23/2022]
Abstract
1. The aim of this study was to evaluate the effect of graded levels of the microbially derived feed lysozyme, muramidase (MUR) on feed intake (FI), weight gain (WG), feed conversion ratio (FCR), European Performance Index (EPI), dietary N-corrected apparent metabolisable energy (AMEn), footpad dermatitis score (FPD) and other welfare variables, when fed to broilers from 0 to 42d age. 2. A four-phase dietary programme and four experimental pelleted diets were used; a control diet (following breeder recommendations without MUR supplementation), and three diets based on the control diet supplemented with 25,000, 35,000 and 45,000 LSU (F)/kg of MUR, respectively. In addition, all experimental diets contained exogenous xylanase, phytase and a coccidiostat. Each diet was fed to birds in 24 pens (20 male Ross 308 chicks in each pen) following randomisation. Dietary AMEn was determined at 21 d of age, and FPD was evaluated at the end of the study. Data were analysed by ANOVA, using orthogonal polynomials for assessing linear and quadratic responses to MUR activity. 3. The inclusion of MUR did not change FI (P > 0.05), but increased WG in a linear manner (P < 0.05) and reduced FCR in a quadratic manner, with optimum WG and FCR observed in birds fed approximately 35 000 LSU (F)/kg. In accordance with the improvement in FCR, 35 000 LSU (F)/kg MUR supplementation produced the highest EPI (P < 0.05). FPD score was linearly decreased with increased addition of MUR (P < 0.05). Dietary AMEn responded in a quadratic fashion to the MUR inclusion, as the highest values were obtained with the highest inclusion rate (P < 0.05). 4. In conclusion, the results showed that inclusion of MUR improved feed efficiency and the foot health of birds.
Collapse
Affiliation(s)
- V Pirgozliev
- NIPH, Harper Adams University , Newport, Shropshire, UK
| | - A Simic
- NIPH, Harper Adams University , Newport, Shropshire, UK
| | - S P Rose
- NIPH, Harper Adams University , Newport, Shropshire, UK
| | - E Pérez Calvo
- DSM Nutritional Products, Animal Nutrition & Health R& D , Village-Neuf, France
| |
Collapse
|
37
|
Maitra A, Munshi T, Healy J, Martin LT, Vollmer W, Keep NH, Bhakta S. Cell wall peptidoglycan in Mycobacterium tuberculosis: An Achilles' heel for the TB-causing pathogen. FEMS Microbiol Rev 2020; 43:548-575. [PMID: 31183501 PMCID: PMC6736417 DOI: 10.1093/femsre/fuz016] [Citation(s) in RCA: 97] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 06/07/2019] [Indexed: 02/06/2023] Open
Abstract
Tuberculosis (TB), caused by the intracellular pathogen Mycobacterium tuberculosis, remains one of the leading causes of mortality across the world. There is an urgent requirement to build a robust arsenal of effective antimicrobials, targeting novel molecular mechanisms to overcome the challenges posed by the increase of antibiotic resistance in TB. Mycobacterium tuberculosis has a unique cell envelope structure and composition, containing a peptidoglycan layer that is essential for maintaining cellular integrity and for virulence. The enzymes involved in the biosynthesis, degradation, remodelling and recycling of peptidoglycan have resurfaced as attractive targets for anti-infective drug discovery. Here, we review the importance of peptidoglycan, including the structure, function and regulation of key enzymes involved in its metabolism. We also discuss known inhibitors of ATP-dependent Mur ligases, and discuss the potential for the development of pan-enzyme inhibitors targeting multiple Mur ligases.
Collapse
Affiliation(s)
- Arundhati Maitra
- Mycobacteria Research Laboratory, Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
| | - Tulika Munshi
- Mycobacteria Research Laboratory, Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
| | - Jess Healy
- Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Liam T Martin
- Mycobacteria Research Laboratory, Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
| | - Waldemar Vollmer
- The Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
| | - Nicholas H Keep
- Mycobacteria Research Laboratory, Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
| | - Sanjib Bhakta
- Mycobacteria Research Laboratory, Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
| |
Collapse
|
38
|
Shaku M, Ealand C, Matlhabe O, Lala R, Kana BD. Peptidoglycan biosynthesis and remodeling revisited. ADVANCES IN APPLIED MICROBIOLOGY 2020; 112:67-103. [PMID: 32762868 DOI: 10.1016/bs.aambs.2020.04.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The bacterial peptidoglycan layer forms a complex mesh-like structure that surrounds the cell, imparting rigidity to withstand cytoplasmic turgor and the ability to tolerate stress. As peptidoglycan has been the target of numerous clinically successful antimicrobials such as penicillin, the biosynthesis, remodeling and recycling of this polymer has been the subject of much interest. Herein, we review recent advances in the understanding of peptidoglycan biosynthesis and remodeling in a variety of different organisms. In order for bacterial cells to grow and divide, remodeling of cross-linked peptidoglycan is essential hence, we also summarize the activity of important peptidoglycan hydrolases and how their functions differ in various species. There is a growing body of evidence highlighting complex regulatory mechanisms for peptidoglycan metabolism including protein interactions, phosphorylation and protein degradation and we summarize key recent findings in this regard. Finally, we provide an overview of peptidoglycan recycling and how components of this pathway mediate resistance to drugs. In the face of growing antimicrobial resistance, these recent advances are expected to uncover new drug targets in peptidoglycan metabolism, which can be used to develop novel therapies.
Collapse
Affiliation(s)
- Moagi Shaku
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, Johannesburg, South Africa
| | - Christopher Ealand
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, Johannesburg, South Africa
| | - Ofentse Matlhabe
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, Johannesburg, South Africa
| | - Rushil Lala
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, Johannesburg, South Africa
| | - Bavesh D Kana
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, Johannesburg, South Africa.
| |
Collapse
|
39
|
Mechanisms of bactericidal action and resistance of polymyxins for Gram-positive bacteria. Appl Microbiol Biotechnol 2020; 104:3771-3780. [PMID: 32157424 DOI: 10.1007/s00253-020-10525-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 02/25/2020] [Accepted: 03/03/2020] [Indexed: 10/24/2022]
Abstract
Polymyxins are cationic antimicrobial peptides used as the last-line therapy to treat multidrug-resistant Gram-negative bacterial infections. The bactericidal activity of polymyxins against Gram-negative bacteria relies on the electrostatic interaction between the positively charged polymyxins and the negatively charged lipid A of lipopolysaccharide (LPS). Given that Gram-positive bacteria lack an LPS-containing outer membrane, it is generally acknowledged that polymyxins are less active against Gram-positive bacteria. However, Gram-positive bacteria produce negatively charged teichoic acids, which may act as the target of polymyxins. More and more studies suggest that polymyxins have potential as a treatment for Gram-positive bacterial infection. This mini-review discusses recent advances in the mechanism of the antibacterial activity and resistance of polymyxins in Gram-positive bacteria.Key Points• Teichoic acids play a key role in the action of polymyxins on Gram-positive bacteria.• Polymyxin kills Gram-positive bacteria by disrupting cell surface and oxidative damage.• Modification of teichoic acids and phospholipids contributes to polymyxin resistance in Gram-positive bacteria.• Polymyxins have potential as a treatment for Gram-positive bacterial infection.
Collapse
|
40
|
Fisher JF, Mobashery S. Constructing and deconstructing the bacterial cell wall. Protein Sci 2020; 29:629-646. [PMID: 31747090 PMCID: PMC7021008 DOI: 10.1002/pro.3737] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 09/17/2019] [Accepted: 09/18/2019] [Indexed: 12/11/2022]
Abstract
The history of modern medicine cannot be written apart from the history of the antibiotics. Antibiotics are cytotoxic secondary metabolites that are isolated from Nature. The antibacterial antibiotics disproportionately target bacterial protein structure that is distinct from eukaryotic protein structure, notably within the ribosome and within the pathways for bacterial cell-wall biosynthesis (for which there is not a eukaryotic counterpart). This review focuses on a pre-eminent class of antibiotics-the β-lactams, exemplified by the penicillins and cephalosporins-from the perspective of the evolving mechanisms for bacterial resistance. The mechanism of action of the β-lactams is bacterial cell-wall destruction. In the monoderm (single membrane, Gram-positive staining) pathogen Staphylococcus aureus the dominant resistance mechanism is expression of a β-lactam-unreactive transpeptidase enzyme that functions in cell-wall construction. In the diderm (dual membrane, Gram-negative staining) pathogen Pseudomonas aeruginosa a dominant resistance mechanism (among several) is expression of a hydrolytic enzyme that destroys the critical β-lactam ring of the antibiotic. The key sensing mechanism used by P. aeruginosa is monitoring the molecular difference between cell-wall construction and cell-wall deconstruction. In both bacteria, the resistance pathways are manifested only when the bacteria detect the presence of β-lactams. This review summarizes how the β-lactams are sensed and how the resistance mechanisms are manifested, with the expectation that preventing these processes will be critical to future chemotherapeutic control of multidrug resistant bacteria.
Collapse
Affiliation(s)
- Jed F. Fisher
- Department of Chemistry and BiochemistryUniversity of Notre DameSouth BendIndiana
| | - Shahriar Mobashery
- Department of Chemistry and BiochemistryUniversity of Notre DameSouth BendIndiana
| |
Collapse
|
41
|
Synergistic antibacterial actions of graphene oxide and antibiotics towards bacteria and the toxicological effects of graphene oxide on human epidermal keratinocytes. Eur J Pharm Sci 2020; 142:105087. [DOI: 10.1016/j.ejps.2019.105087] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 08/24/2019] [Accepted: 09/21/2019] [Indexed: 02/06/2023]
|
42
|
Identification and Characterization of a Cell Wall Hydrolase for Sporangiospore Maturation in Actinoplanes missouriensis. J Bacteriol 2019; 201:JB.00519-19. [PMID: 31570527 DOI: 10.1128/jb.00519-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 09/23/2019] [Indexed: 11/20/2022] Open
Abstract
The rare actinomycete Actinoplanes missouriensis grows as substrate mycelium and forms terminal sporangia containing a few hundred spores as dormant cells. Upon contact with water, the sporangia open up and release spores to external environments. Here, we report a cell wall hydrolase, GsmA, that is required for sporangiospore maturation in A. missouriensis The gsmA gene is conserved among Actinoplanes species and several species of other rare actinomycetes. Transcription of gsmA is activated in the late stage of sporangium formation by the global transcriptional activator TcrA, which is involved in sporangium formation and dehiscence. GsmA is composed of an N-terminal signal peptide for the twin arginine translocation pathway, two tandem bacterial SH3-like domains, and a glucosaminidase domain. Zymographic analysis using a recombinant C-terminal glucosaminidase domain protein showed that GsmA is a hydrolase able to digest cell walls extracted from the vegetative mycelia of A. missouriensis and Streptomyces griseus A gsmA deletion mutant (ΔgsmA) formed apparently normal sporangia, but they released chains of 2 to 20 spores under sporangium dehiscence-inducing conditions, indicating that spores did not completely mature in the mutant sporangia. From these results, we concluded that GsmA is a cell wall hydrolase for digesting peptidoglycan at septum-forming sites to separate adjacent spores during sporangiospore maturation in A. missouriensis Unexpectedly, flagella were observed around the spore chains of the ΔgsmA mutant by transmission electron microscopy. The flagellar formation was strictly restricted to cell-cell interfaces, giving an important insight into the polarity of the flagellar biogenesis in a spherical spore.IMPORTANCE In streptomycetes, an aerial hypha is compartmentalized by multiple septations into prespores, which become spores through a series of maturation processes. However, little is known about these maturation processes. The rare actinomycete Actinoplanes missouriensis produces sporangiospores, which are assumed to be formed also from prespores generated by the compartmentalization of intrasporangium hyphae via septation. The identification of GsmA as a cell wall hydrolase for the separation of adjacent spores sheds light on the almost unknown processes of sporangiospore formation in A. missouriensis Furthermore, the fact that GsmA orthologues are conserved within the genus Actinoplanes but not in streptomycetes indicates that Actinoplanes has developed an original strategy for the spore maturation in a specific environment, that is, inside a sporangium.
Collapse
|
43
|
Schäpe SS, Krause JL, Engelmann B, Fritz-Wallace K, Schattenberg F, Liu Z, Müller S, Jehmlich N, Rolle-Kampczyk U, Herberth G, von Bergen M. The Simplified Human Intestinal Microbiota (SIHUMIx) Shows High Structural and Functional Resistance against Changing Transit Times in In Vitro Bioreactors. Microorganisms 2019; 7:E641. [PMID: 31816881 PMCID: PMC6956075 DOI: 10.3390/microorganisms7120641] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 01/10/2023] Open
Abstract
Many functions in host-microbiota interactions are potentially influenced by intestinal transit times, but little is known about the effects of altered transition times on the composition and functionality of gut microbiota. To analyze these effects, we cultivated the model community SIHUMIx in bioreactors in order to determine the effects of varying transit times (TT) on the community structure and function. After five days of continuous cultivation, we investigated the influence of different medium TT of 12 h, 24 h, and 48 h. For profiling the microbial community, we applied flow cytometric fingerprinting and revealed changes in the community structure of SIHUMIx during the change of TT, which were not associated with changes in species abundances. For pinpointing metabolic alterations, we applied metaproteomics and metabolomics and found, along with shortening the TT, a slight decrease in glycan biosynthesis, carbohydrate, and amino acid metabolism and, furthermore, a reduction in butyrate, methyl butyrate, isobutyrate, valerate, and isovalerate concentrations. Specifically, B. thetaiotaomicron was identified to be affected in terms of butyrate metabolism. However, communities could recover to the original state afterward. This study shows that SIHUMIx showed high structural stability when TT changed-even four-fold. Resistance values remained high, which suggests that TTs did not interfere with the structure of the community to a certain degree.
Collapse
Affiliation(s)
- Stephanie Serena Schäpe
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (S.S.S.); (B.E.); (K.F.-W.); (N.J.); (U.R.-K.)
| | - Jannike Lea Krause
- Department of Environmental Immunology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (J.L.K.); (G.H.)
| | - Beatrice Engelmann
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (S.S.S.); (B.E.); (K.F.-W.); (N.J.); (U.R.-K.)
| | - Katarina Fritz-Wallace
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (S.S.S.); (B.E.); (K.F.-W.); (N.J.); (U.R.-K.)
| | - Florian Schattenberg
- Department of Environmental Microbiology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (F.S.); (Z.L.); (S.M.)
| | - Zishu Liu
- Department of Environmental Microbiology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (F.S.); (Z.L.); (S.M.)
| | - Susann Müller
- Department of Environmental Microbiology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (F.S.); (Z.L.); (S.M.)
| | - Nico Jehmlich
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (S.S.S.); (B.E.); (K.F.-W.); (N.J.); (U.R.-K.)
| | - Ulrike Rolle-Kampczyk
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (S.S.S.); (B.E.); (K.F.-W.); (N.J.); (U.R.-K.)
| | - Gunda Herberth
- Department of Environmental Immunology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (J.L.K.); (G.H.)
| | - Martin von Bergen
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research―UFZ GmbH, 04316 Leipzig, Germany; (S.S.S.); (B.E.); (K.F.-W.); (N.J.); (U.R.-K.)
- Institute of Biochemistry, Faculty of Biosciences, Pharmacy and Psychology, University of Leipzig, 04103 Leipzig, Germany
| |
Collapse
|
44
|
Muropeptides Stimulate Growth Resumption from Stationary Phase in Escherichia coli. Sci Rep 2019; 9:18043. [PMID: 31792329 PMCID: PMC6888817 DOI: 10.1038/s41598-019-54646-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 11/18/2019] [Indexed: 12/19/2022] Open
Abstract
When nutrients run out, bacteria enter a dormant metabolic state. This low or undetectable metabolic activity helps bacteria to preserve their scant reserves for the future needs, yet it also diminishes their ability to scan the environment for new growth-promoting substrates. However, neighboring microbial growth is a reliable indicator of a favorable environment and can thus serve as a cue for exiting dormancy. Here we report that for Escherichia coli and Pseudomonas aeruginosa this cue is provided by the basic peptidoglycan unit (i.e. muropeptide). We show that several forms of muropeptides from a variety of bacterial species can stimulate growth resumption of dormant cells and the sugar – peptide bond is crucial for this activity. These results, together with previous research that identifies muropeptides as a germination signal for bacterial spores, and their detection by mammalian immune cells, show that muropeptides are a universal cue for bacterial growth.
Collapse
|
45
|
Dörr T, Moynihan PJ, Mayer C. Editorial: Bacterial Cell Wall Structure and Dynamics. Front Microbiol 2019; 10:2051. [PMID: 31551985 PMCID: PMC6737391 DOI: 10.3389/fmicb.2019.02051] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 08/20/2019] [Indexed: 12/23/2022] Open
Affiliation(s)
- Tobias Dörr
- Department of Microbiology, Weill Institute for Cell and Molecular Biology, Ithaca, NY, United States.,Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, NY, United States
| | - Patrick J Moynihan
- School of Biosciences, Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Christoph Mayer
- Department of Biology, Interfaculty Institute of Microbiology and Infection Medicine Tübingen, University of Tübingen, Tübingen, Germany
| |
Collapse
|
46
|
Mayer C, Kluj RM, Mühleck M, Walter A, Unsleber S, Hottmann I, Borisova M. Bacteria's different ways to recycle their own cell wall. Int J Med Microbiol 2019; 309:151326. [PMID: 31296364 DOI: 10.1016/j.ijmm.2019.06.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 05/28/2019] [Accepted: 06/30/2019] [Indexed: 01/05/2023] Open
Abstract
The ability to recover components of their own cell wall is a common feature of bacteria. This was initially recognized in the Gram-negative bacterium Escherichia coli, which recycles about half of the peptidoglycan of its cell wall during one cell doubling. Moreover, E. coli was shown to grow on peptidoglycan components provided as nutrients. A distinguished recycling enzyme of E. coli required for both, recovery of the cell wall sugar N-acetylmuramic acid (MurNAc) of the own cell wall and for growth on external MurNAc, is the MurNAc 6-phosphate (MurNAc 6P) lactyl ether hydrolase MurQ. We revealed however, that most Gram-negative bacteria lack a murQ ortholog and instead harbor a pathway, absent in E. coli, that channels MurNAc directly to peptidoglycan biosynthesis. This "anabolic recycling pathway" bypasses the initial steps of peptidoglycan de novo synthesis, including the target of the antibiotic fosfomycin, thus providing intrinsic resistance to the antibiotic. The Gram-negative oral pathogen Tannerella forsythia is auxotrophic for MurNAc and apparently depends on the anabolic recycling pathway to synthesize its own cell wall by scavenging cell wall debris of other bacteria. In contrast, Gram-positive bacteria lack the anabolic recycling genes, but mostly contain one or two murQ orthologs. Quantification of MurNAc 6P accumulation in murQ mutant cells by mass spectrometry allowed us to demonstrate for the first time that Gram-positive bacteria do recycle their own peptidoglycan. This had been questioned earlier, since peptidoglycan turnover products accumulate in the spent media of Gram-positives. We showed, that these fragments are recovered during nutrient limitation, which prolongs starvation survival of Bacillus subtilis and Staphylococcus aureus. Peptidoglycan recycling in these bacteria however differs, as the cell wall is either cleaved exhaustively and monosaccharide building blocks are taken up (B. subtilis) or disaccharides are released and recycled involving a novel phosphomuramidase (MupG; S.aureus). In B. subtilis also the teichoic acids, covalently bound to the peptidoglycan (wall teichoic acids; WTAs), are recycled. During phosphate limitation, the sn-glycerol-3-phosphate phosphodiesterase GlpQ specifically degrades WTAs of B. subtilis. In S. aureus, in contrast, GlpQ is used to scavenge external teichoic acid sources. Thus, although bacteria generally recover their own cell wall, they apparently apply distinct strategies for breakdown and reutilization of cell wall fragments. This review summarizes our work on this topic funded between 2011 and 2019 by the DFG within the collaborative research center SFB766.
Collapse
Affiliation(s)
- Christoph Mayer
- Mikrobiologie/Biotechnologie, Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany.
| | - Robert Maria Kluj
- Mikrobiologie/Biotechnologie, Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Maraike Mühleck
- Mikrobiologie/Biotechnologie, Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Axel Walter
- Mikrobiologie/Biotechnologie, Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Sandra Unsleber
- Mikrobiologie/Biotechnologie, Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Isabel Hottmann
- Mikrobiologie/Biotechnologie, Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Marina Borisova
- Mikrobiologie/Biotechnologie, Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| |
Collapse
|
47
|
Porfírio S, Carlson RW, Azadi P. Elucidating Peptidoglycan Structure: An Analytical Toolset. Trends Microbiol 2019; 27:607-622. [DOI: 10.1016/j.tim.2019.01.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 01/16/2019] [Accepted: 01/29/2019] [Indexed: 01/04/2023]
|
48
|
The hydrolase LpqI primes mycobacterial peptidoglycan recycling. Nat Commun 2019; 10:2647. [PMID: 31201321 PMCID: PMC6572805 DOI: 10.1038/s41467-019-10586-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 05/14/2019] [Indexed: 12/26/2022] Open
Abstract
Growth and division by most bacteria requires remodelling and cleavage of their cell wall. A byproduct of this process is the generation of free peptidoglycan (PG) fragments known as muropeptides, which are recycled in many model organisms. Bacteria and hosts can harness the unique nature of muropeptides as a signal for cell wall damage and infection, respectively. Despite this critical role for muropeptides, it has long been thought that pathogenic mycobacteria such as Mycobacterium tuberculosis do not recycle their PG. Herein we show that M. tuberculosis and Mycobacterium bovis BCG are able to recycle components of their PG. We demonstrate that the core mycobacterial gene lpqI, encodes an authentic NagZ β-N-acetylglucosaminidase and that it is essential for PG-derived amino sugar recycling via an unusual pathway. Together these data provide a critical first step in understanding how mycobacteria recycle their peptidoglycan. Bacterial growth and division require remodelling of the cell wall, which generates free peptidoglycan fragments. Here, Moynihan et al. show that Mycobacterium tuberculosis can recycle components of their peptidoglycan, and characterise a crucial enzyme required for this process.
Collapse
|
49
|
Martin‐Cuadrado A, Senel E, Martínez‐García M, Cifuentes A, Santos F, Almansa C, Moreno‐Paz M, Blanco Y, García‐Villadangos M, Cura MÁG, Sanz‐Montero ME, Rodríguez‐Aranda JP, Rosselló‐Móra R, Antón J, Parro V. Prokaryotic and viral community of the sulfate‐rich crust from Peñahueca ephemeral lake, an astrobiology analogue. Environ Microbiol 2019; 21:3577-3600. [DOI: 10.1111/1462-2920.14680] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 05/09/2019] [Accepted: 05/11/2019] [Indexed: 11/29/2022]
Affiliation(s)
| | - Ece Senel
- Department of Physiology, Genetics and MicrobiologyUniversity of Alicante Alicante Spain
- Department of BiologyGraduate School of Sciences, Eskisehir Technical University Yunusemre Campus, Eskisehir 26470 Turkey
| | - Manuel Martínez‐García
- Department of Physiology, Genetics and MicrobiologyUniversity of Alicante Alicante Spain
| | - Ana Cifuentes
- Department of Ecology and Marine Resources, Marine Microbiology GroupMediterranean Institute for Advanced Studies (IMEDEA, CSIC‐UIB) Esporles Spain
| | - Fernando Santos
- Department of Physiology, Genetics and MicrobiologyUniversity of Alicante Alicante Spain
| | - Cristina Almansa
- Research Technical Services (SSTTI), Microscopy UnitUniversity of Alicante Alicante Spain
| | - Mercedes Moreno‐Paz
- Department of Molecular EvolutionCentro de Astrobiología (INTA‐CSIC) Madrid Spain
| | - Yolanda Blanco
- Department of Molecular EvolutionCentro de Astrobiología (INTA‐CSIC) Madrid Spain
| | | | | | | | | | - Ramon Rosselló‐Móra
- Department of BiologyGraduate School of Sciences, Eskisehir Technical University Yunusemre Campus, Eskisehir 26470 Turkey
| | - Josefa Antón
- Department of Physiology, Genetics and MicrobiologyUniversity of Alicante Alicante Spain
| | - Víctor Parro
- Department of Molecular EvolutionCentro de Astrobiología (INTA‐CSIC) Madrid Spain
| |
Collapse
|
50
|
Abstract
The chapter about the Gram-positive bacterial cell wall gives a brief historical background on the discovery of Gram-positive cell walls and their constituents and microscopic methods applied for studying the Gram-positive cell envelope. Followed by the description of the different chemical building blocks of peptidoglycan and the biosynthesis of the peptidoglycan layers and high turnover of peptidoglycan during bacterial growth. Lipoteichoic acids and wall teichoic acids are highlighted as major components of the cell wall. Characterization of capsules and the formation of extracellular vesicles by Gram-positive bacteria close the section on cell envelopes which have a high impact on bacterial pathogenesis. In addition, the specialized complex and unusual cell wall of mycobacteria is introduced thereafter. Next a short back view is given on the development of electron microscopic examinations for studying bacterial cell walls. Different electron microscopic techniques and methods applied to examine bacterial cell envelopes are discussed in the view that most of the illustrated methods should be available in a well-equipped life sciences orientated electron microscopic laboratory. In addition, newly developed and mostly well-established cryo-methods like high-pressure freezing and freeze-substitution (HPF-FS) and cryo-sections of hydrated vitrified bacteria (CEMOVIS, Cryo-electron microscopy of vitreous sections) are described. At last, modern cryo-methods like cryo-electron tomography (CET) and cryo-FIB-SEM milling (focus ion beam-scanning electron microscopy) are introduced which are available only in specialized institutions, but at present represent the best available methods and techniques to study Gram-positive cell walls under close-to-nature conditions in great detail and at high resolution.
Collapse
Affiliation(s)
- Manfred Rohde
- Helmholtz Centre for Infection Research, HZI, Central Facility for Microscopy, ZEIM, Braunschweig, Germany
| |
Collapse
|