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Nair ZJ, Gao IH, Firras A, Chong KKL, Hill ED, Choo PY, Colomer-Winter C, Chen Q, Manzano C, Pethe K, Kline KA. An essential protease, FtsH, influences daptomycin resistance acquisition in Enterococcus faecalis. Mol Microbiol 2024; 121:1021-1038. [PMID: 38527904 DOI: 10.1111/mmi.15253] [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: 07/31/2023] [Revised: 03/11/2024] [Accepted: 03/11/2024] [Indexed: 03/27/2024]
Abstract
Daptomycin is a last-line antibiotic commonly used to treat vancomycin-resistant Enterococci, but resistance evolves rapidly and further restricts already limited treatment options. While genetic determinants associated with clinical daptomycin resistance (DAPR) have been described, information on factors affecting the speed of DAPR acquisition is limited. The multiple peptide resistance factor (MprF), a phosphatidylglycerol-modifying enzyme involved in cationic antimicrobial resistance, is linked to DAPR in pathogens such as methicillin-resistant Staphylococcus aureus. Since Enterococcus faecalis encodes two paralogs of mprF and clinical DAPR mutations do not map to mprF, we hypothesized that functional redundancy between the paralogs prevents mprF-mediated resistance and masks other evolutionary pathways to DAPR. Here, we performed in vitro evolution to DAPR in mprF mutant background. We discovered that the absence of mprF results in slowed DAPR evolution and is associated with inactivating mutations in ftsH, resulting in the depletion of the chaperone repressor HrcA. We also report that ftsH is essential in the parental, but not in the ΔmprF, strain where FtsH depletion results in growth impairment in the parental strain, a phenotype associated with reduced extracellular acidification and reduced ability for metabolic reduction. This presents FtsH and HrcA as enticing targets for developing anti-resistance strategies.
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Affiliation(s)
- Zeus Jaren Nair
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Drug Resistance Interdisciplinary Research Group, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Interdisciplinary Graduate Programme, Graduate College, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Iris Hanxing Gao
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Aslam Firras
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Kelvin Kian Long Chong
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Interdisciplinary Graduate Programme, Graduate College, Nanyang Technological University, Singapore, Singapore
| | - Eric D Hill
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, Singapore
| | - Pei Yi Choo
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Cristina Colomer-Winter
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Qingyan Chen
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Caroline Manzano
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Kevin Pethe
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Drug Resistance Interdisciplinary Research Group, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
- National Centre for Infectious Diseases (NCID), Singapore, Singapore
| | - Kimberly A Kline
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Drug Resistance Interdisciplinary Research Group, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
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Mawla GD, Kamal SM, Cao LY, Purhonen P, Hebert H, Sauer RT, Baker TA, Römling U. The membrane-cytoplasmic linker defines activity of FtsH proteases in Pseudomonas aeruginosa clone C. J Biol Chem 2024; 300:105622. [PMID: 38176647 PMCID: PMC10850787 DOI: 10.1016/j.jbc.2023.105622] [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: 08/12/2023] [Revised: 12/22/2023] [Accepted: 12/27/2023] [Indexed: 01/06/2024] Open
Abstract
Pandemic Pseudomonas aeruginosa clone C strains encode two inner-membrane associated ATP-dependent FtsH proteases. PaftsH1 is located on the core genome and supports cell growth and intrinsic antibiotic resistance, whereas PaftsH2, a xenolog acquired through horizontal gene transfer from a distantly related species, is unable to functionally replace PaftsH1. We show that purified PaFtsH2 degrades fewer substrates than PaFtsH1. Replacing the 31-amino acid-extended linker region of PaFtsH2 spanning from the C-terminal end of the transmembrane helix-2 to the first seven highly divergent residues of the cytosolic AAA+ ATPase module with the corresponding region of PaFtsH1 improves hybrid-enzyme substrate processing in vitro and enables PaFtsH2 to substitute for PaFtsH1 in vivo. Electron microscopy indicates that the identity of this linker sequence influences FtsH flexibility. We find membrane-cytoplasmic (MC) linker regions of PaFtsH1 characteristically glycine-rich compared to those from FtsH2. Consequently, introducing three glycines into the membrane-proximal end of PaFtsH2's MC linker is sufficient to elevate its activity in vitro and in vivo. Our findings establish that the efficiency of substrate processing by the two PaFtsH isoforms depends on MC linker identity and suggest that greater linker flexibility and/or length allows FtsH to degrade a wider spectrum of substrates. As PaFtsH2 homologs occur across bacterial phyla, we hypothesize that FtsH2 is a latent enzyme but may recognize specific substrates or is activated in specific contexts or biological niches. The identity of such linkers might thus play a more determinative role in the functionality of and physiological impact by FtsH proteases than previously thought.
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Affiliation(s)
- Gina D Mawla
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Shady M Kamal
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm; Sweden
| | - Lian-Ying Cao
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm; Sweden
| | - Pasi Purhonen
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Huddinge; Sweden
| | - Hans Hebert
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Huddinge; Sweden
| | - Robert T Sauer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Tania A Baker
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
| | - Ute Römling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm; Sweden.
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Benigno V, Carraro N, Sarton-Lohéac G, Romano-Bertrand S, Blanc DS, van der Meer JR. Diversity and evolution of an abundant ICE clc family of integrative and conjugative elements in Pseudomonas aeruginosa. mSphere 2023; 8:e0051723. [PMID: 37902330 PMCID: PMC10732049 DOI: 10.1128/msphere.00517-23] [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: 09/08/2023] [Accepted: 09/24/2023] [Indexed: 10/31/2023] Open
Abstract
IMPORTANCE Microbial populations swiftly adapt to changing environments through horizontal gene transfer. While the mechanisms of gene transfer are well known, the impact of environmental conditions on the selection of transferred gene functions remains less clear. We investigated ICEs, specifically the ICEclc-type, in Pseudomonas aeruginosa clinical isolates. Our findings revealed co-evolution between ICEs and their hosts, with ICE transfers occurring within strains. Gene functions carried by ICEs are positively selected, including potential virulence factors and heavy metal resistance. Comparison to publicly available P. aeruginosa genomes unveiled widespread antibiotic-resistance determinants within ICEclc clades. Thus, the ubiquitous ICEclc family significantly contributes to P. aeruginosa's adaptation and fitness in diverse environments.
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Affiliation(s)
- Valentina Benigno
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Nicolas Carraro
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Garance Sarton-Lohéac
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Sara Romano-Bertrand
- Hydrosciences Montpellier, IRD, CNRS, University of Montpellier, Hospital Hygiene and Infection Control Team, University Hospital of Montpellier, Montpellier, France
| | - Dominique S. Blanc
- Prevention and Infection Control Unit, Infectious Diseases Service, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
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Kim H, Moon S, Ham S, Lee K, Römling U, Lee C. Cytoplasmic molecular chaperones in Pseudomonas species. J Microbiol 2022; 60:1049-1060. [PMID: 36318358 DOI: 10.1007/s12275-022-2425-0] [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: 09/21/2022] [Revised: 10/20/2022] [Accepted: 10/20/2022] [Indexed: 06/16/2023]
Abstract
Pseudomonas is widespread in various environmental and host niches. To promote rejuvenation, cellular protein homeostasis must be finely tuned in response to diverse stresses, such as extremely high and low temperatures, oxidative stress, and desiccation, which can result in protein homeostasis imbalance. Molecular chaperones function as key components that aid protein folding and prevent protein denaturation. Pseudomonas, an ecologically important bacterial genus, includes human and plant pathogens as well as growth-promoting symbionts and species useful for bioremediation. In this review, we focus on protein quality control systems, particularly molecular chaperones, in ecologically diverse species of Pseudomonas, including the opportunistic human pathogen Pseudomonas aeruginosa, the plant pathogen Pseudomonas syringae, the soil species Pseudomonas putida, and the psychrophilic Pseudomonas antarctica.
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Affiliation(s)
- Hyunhee Kim
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea
| | - Seongjoon Moon
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea
| | - Soojeong Ham
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea
| | - Kihyun Lee
- CJ Bioscience, Seoul, 04527, Republic of Korea
| | - Ute Römling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Changhan Lee
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea.
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Spero MA, Jones J, Lomenick B, Chou TF, Newman DK. Mechanisms of chlorate toxicity and resistance in Pseudomonas aeruginosa. Mol Microbiol 2022; 118:321-335. [PMID: 36271736 PMCID: PMC9589919 DOI: 10.1111/mmi.14972] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 07/31/2022] [Accepted: 08/04/2022] [Indexed: 11/28/2022]
Abstract
Pseudomonas aeruginosa is an opportunistic bacterial pathogen that often encounters hypoxic/anoxic environments within the host, which increases its tolerance to many conventional antibiotics. Toward identifying novel treatments, we explored the therapeutic potential of chlorate, a pro-drug that kills hypoxic/anoxic, antibiotic-tolerant P. aeruginosa populations. While chlorate itself is relatively nontoxic, it is enzymatically reduced to the toxic oxidizing agent, chlorite, by hypoxically induced nitrate reductase. To better assess chlorate's therapeutic potential, we investigated mechanisms of chlorate toxicity and resistance in P. aeruginosa. We used transposon mutagenesis to identify genes that alter P. aeruginosa fitness during chlorate treatment, finding that methionine sulfoxide reductases (Msr), which repair oxidized methionine residues, support survival during chlorate stress. Chlorate treatment leads to proteome-wide methionine oxidation, which is exacerbated in a ∆msrA∆msrB strain. In response to chlorate, P. aeruginosa upregulates proteins involved in a wide range of functions, including metabolism, DNA replication/repair, protein repair, transcription, and translation, and these newly synthesized proteins are particularly vulnerable to methionine oxidation. The addition of exogenous methionine partially rescues P. aeruginosa survival during chlorate treatment, suggesting that widespread methionine oxidation contributes to death. Finally, we found that mutations that decrease nitrate reductase activity are a common mechanism of chlorate resistance.
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Affiliation(s)
- Melanie A. Spero
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Present address: Institute of Molecular Biology, University of Oregon, Eugene, OR, USA
| | - Jeff Jones
- Proteome Exploration Laboratory, Beckman Institute, Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Brett Lomenick
- Proteome Exploration Laboratory, Beckman Institute, Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Tsui-Fen Chou
- Proteome Exploration Laboratory, Beckman Institute, Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Dianne K. Newman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
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Valzano F, Boncompagni SR, Micieli M, Di Maggio T, Di Pilato V, Colombini L, Santoro F, Pozzi G, Rossolini GM, Pallecchi L. Activity of N-Acetylcysteine Alone and in Combination with Colistin against Pseudomonas aeruginosa Biofilms and Transcriptomic Response to N-Acetylcysteine Exposure. Microbiol Spectr 2022; 10:e0100622. [PMID: 35735984 PMCID: PMC9431628 DOI: 10.1128/spectrum.01006-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 06/03/2022] [Indexed: 11/25/2022] Open
Abstract
Chronic colonization by Pseudomonas aeruginosa is critical in cystic fibrosis (CF) and other chronic lung diseases, contributing to disease progression. Biofilm growth and a propensity to evolve multidrug resistance phenotypes drastically limit the available therapeutic options. In this perspective, there has been growing interest in evaluating combination therapies, especially for drugs that can be administered by nebulization, which allows high drug concentrations to be reached at the site of infections while limiting systemic toxicity. Here, we investigated the potential antibiofilm activity of N-acetylcysteine (NAC) alone and in combination with colistin against a panel of P. aeruginosa strains (most of which are from CF patients) and the transcriptomic response of a P. aeruginosa CF strain to NAC exposure. NAC alone (8,000 mg/L) showed a limited and strain-dependent antibiofilm activity. Nonetheless, a relevant antibiofilm synergism of NAC-colistin combinations (NAC at 8,000 mg/L plus colistin at 2 to 32 mg/L) was observed with all strains. Synergism was also confirmed with the artificial sputum medium model. RNA sequencing of NAC-exposed planktonic cultures revealed that NAC (8,000 mg/L) mainly induced (i) a Zn2+ starvation response (known to induce attenuation of P. aeruginosa virulence), (ii) downregulation of genes of the denitrification apparatus, and (iii) downregulation of flagellar biosynthesis pathway. NAC-mediated inhibition of P. aeruginosa denitrification pathway and flagellum-mediated motility were confirmed experimentally. These findings suggested that NAC-colistin combinations might contribute to the management of biofilm-associated P. aeruginosa lung infections. NAC might also have a role in reducing P. aeruginosa virulence, which could be relevant in the very early stages of lung colonization. IMPORTANCE Pseudomonas aeruginosa biofilm-related chronic lung colonization contributes to cystic fibrosis (CF) disease progression. Colistin is often a last-resort antibiotic for the treatment of such P. aeruginosa infections, and it has been increasingly used in CF, especially by nebulization. N-acetylcysteine (NAC) is a mucolytic agent with antioxidant activity, commonly administered with antibiotics for the treatment of lower respiratory tract infections. Here, we show that NAC potentiated colistin activity against in vitro biofilms models of P. aeruginosa strains, with both drugs tested at the high concentrations achievable after nebulization. In addition, we report the first transcriptomic data on the P. aeruginosa response to NAC exposure.
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Affiliation(s)
- Felice Valzano
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | | | - Maria Micieli
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Tiziana Di Maggio
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Vincenzo Di Pilato
- Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy
| | - Lorenzo Colombini
- Laboratory of Molecular Microbiology and Biotechnology, Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Francesco Santoro
- Laboratory of Molecular Microbiology and Biotechnology, Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Gianni Pozzi
- Laboratory of Molecular Microbiology and Biotechnology, Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Gian Maria Rossolini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
- Clinical Microbiology and Virology Unit, Careggi University Hospital, Florence, Italy
| | - Lucia Pallecchi
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
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Pu T, Mo Z, Su L, Yang J, Wan K, Wang L, Liu R, Liu Y. Genome-wide identification and expression analysis of the ftsH protein family and its response to abiotic stress in Nicotiana tabacum L. BMC Genomics 2022; 23:503. [PMID: 35831784 PMCID: PMC9281163 DOI: 10.1186/s12864-022-08719-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 06/23/2022] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The filamentous temperature-sensitive H protease (ftsH) gene family plays an important role in plant growth and development. FtsH proteins belong to the AAA protease family. Studies have shown that it is a key gene for plant chloroplast development and photosynthesis regulation. In addition, the ftsH gene is also involved in plant response to stress. At present, the research and analysis of the ftsH gene family are conducted in microorganisms such as Escherichia coli and Oenococcus and various plants such as Arabidopsis, pear, rice, and corn. However, analysis reports on ftsH genes from tobacco (Nicotiana tabacum L.), an important model plant, are still lacking. Since ftsH genes regulate plant growth and development, it has become necessary to systematically study this gene in an economically important plant like tobacco. RESULTS This is the first study to analyze the ftsH gene from Nicotiana tabacum L. K326 (NtftsH). We identified 20 ftsH genes from the whole genome sequence, renamed them according to their chromosomal locations, and divided them into eight subfamilies. These 20 NtftsH genes were unevenly distributed across the 24 chromosomes. We found four pairs of fragment duplications. We further investigated the collinearity between these genes and related genes in five other species. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis identified differential expression patterns of NtftsH in different tissues and under various abiotic stress conditions. CONCLUSIONS This study provides a comprehensive analysis of the NtftsH gene family. The exon-intron structure and motif composition are highly similar in NtftsH genes that belong to the same evolutionary tree branch. Homology analysis and phylogenetic comparison of ftsH genes from several different plants provide valuable clues for studying the evolutionary characteristics of NtftsH genes. The NtftsH genes play important roles in plant growth and development, revealed by their expression levels in different tissues as well as under different stress conditions. Gene expression and phylogenetic analyses will provide the basis for the functional analysis of NtftsH genes. These results provide a valuable resource for a better understanding of the biological role of the ftsH genes in the tobacco plant.
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Affiliation(s)
- Tianxiunan Pu
- Guizhou Province, College of Tobacco Science of Guizhou University/ Guizhou Key Laboratory for Tobacco Quality, Huaxi District, Guiyang City, 550025, People's Republic of China
| | - Zejun Mo
- Guizhou Province, College of Tobacco Science of Guizhou University/ Guizhou Key Laboratory for Tobacco Quality, Huaxi District, Guiyang City, 550025, People's Republic of China
| | - Long Su
- Guizhou Province, College of Tobacco Science of Guizhou University/ Guizhou Key Laboratory for Tobacco Quality, Huaxi District, Guiyang City, 550025, People's Republic of China
| | - Jing Yang
- Guizhou Province, College of Tobacco Science of Guizhou University/ Guizhou Key Laboratory for Tobacco Quality, Huaxi District, Guiyang City, 550025, People's Republic of China
| | - Ke Wan
- Guizhou Province, College of Tobacco Science of Guizhou University/ Guizhou Key Laboratory for Tobacco Quality, Huaxi District, Guiyang City, 550025, People's Republic of China
| | - Linqi Wang
- Guizhou Province, College of Tobacco Science of Guizhou University/ Guizhou Key Laboratory for Tobacco Quality, Huaxi District, Guiyang City, 550025, People's Republic of China
| | - Renxiang Liu
- Guizhou Province, College of Tobacco Science of Guizhou University/ Guizhou Key Laboratory for Tobacco Quality, Huaxi District, Guiyang City, 550025, People's Republic of China
| | - Yang Liu
- Guizhou Province, College of Tobacco Science of Guizhou University/ Guizhou Key Laboratory for Tobacco Quality, Huaxi District, Guiyang City, 550025, People's Republic of China.
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Atanaskovic I, Sharp C, Press C, Kaminska R, Kleanthous C. Bacterial Competition Systems Share a Domain Required for Inner Membrane Transport of the Bacteriocin Pyocin G from Pseudomonas aeruginosa. mBio 2022; 13:e0339621. [PMID: 35343790 PMCID: PMC9040868 DOI: 10.1128/mbio.03396-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 02/28/2022] [Indexed: 02/06/2023] Open
Abstract
Bacteria exploit a variety of attack strategies to gain dominance within ecological niches. Prominent among these are contact-dependent inhibition (CDI), type VI secretion (T6SS), and bacteriocins. The cytotoxic endpoint of these systems is often the delivery of a nuclease to the cytosol. How such nucleases translocate across the cytoplasmic membrane of Gram-negative bacteria is unknown. Here, we identify a small, conserved, 15-kDa domain, which we refer to as the inner membrane translocation (IMT) domain, that is common to T6SS and bacteriocins and linked to nuclease effector domains. Through fluorescence microscopy assays using intact and spheroplasted cells, we demonstrate that the IMT domain of the Pseudomonas aeruginosa-specific bacteriocin pyocin G (PyoG) is required for import of the toxin nuclease domain to the cytoplasm. We also show that translocation of PyoG into the cytosol is dependent on inner membrane proteins FtsH, a AAA+ATPase/protease, and TonB1, the latter more typically associated with transport of bacteriocins across the outer membrane. Our study reveals that the IMT domain directs the cytotoxic nuclease of PyoG to cross the cytoplasmic membrane and, more broadly, has been adapted for the transport of other toxic nucleases delivered into Gram-negative bacteria by both contact-dependent and contact-independent means. IMPORTANCE Nuclease bacteriocins are potential antimicrobials for the treatment of antibiotic-resistant bacterial infections. While the mechanism of outer membrane translocation is beginning to be understood, the mechanism of inner membrane transport is not known. This study uses PyoG as a model nuclease bacteriocin and defines a conserved domain that is essential for inner membrane translocation and is widespread in other bacterial competition systems. Additionally, the presented data link two membrane proteins, FtsH and TonB1, with inner membrane translocation of PyoG. These findings point to the general importance of this domain to the cellular uptake mechanisms of nucleases delivered by otherwise diverse and distinct bacterial competition systems. The work is also of importance for the design of new protein antibiotics.
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Affiliation(s)
- Iva Atanaskovic
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Connor Sharp
- Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Cara Press
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Renata Kaminska
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Colin Kleanthous
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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Yi L, Liu B, Nixon PJ, Yu J, Chen F. Recent Advances in Understanding the Structural and Functional Evolution of FtsH Proteases. FRONTIERS IN PLANT SCIENCE 2022; 13:837528. [PMID: 35463435 PMCID: PMC9020784 DOI: 10.3389/fpls.2022.837528] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 02/24/2022] [Indexed: 05/18/2023]
Abstract
The FtsH family of proteases are membrane-anchored, ATP-dependent, zinc metalloproteases. They are universally present in prokaryotes and the mitochondria and chloroplasts of eukaryotic cells. Most bacteria bear a single ftsH gene that produces hexameric homocomplexes with diverse house-keeping roles. However, in mitochondria, chloroplasts and cyanobacteria, multiple FtsH homologs form homo- and heterocomplexes with specialized functions in maintaining photosynthesis and respiration. The diversification of FtsH homologs combined with selective pairing of FtsH isomers is a versatile strategy to enable functional adaptation. In this article we summarize recent progress in understanding the evolution, structure and function of FtsH proteases with a focus on the role of FtsH in photosynthesis and respiration.
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Affiliation(s)
- Lanbo Yi
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Institute for Innovative Development of Food Industry, Shenzhen University, Shenzhen, China
| | - Bin Liu
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Institute for Innovative Development of Food Industry, Shenzhen University, Shenzhen, China
| | - Peter J. Nixon
- Sir Ernst Chain Building-Wolfson Laboratories, Department of Life Sciences, Imperial College London, London, United Kingdom
- *Correspondence: Peter J. Nixon, ; orcid.org/0000-0003-1952-6937
| | - Jianfeng Yu
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Sir Ernst Chain Building-Wolfson Laboratories, Department of Life Sciences, Imperial College London, London, United Kingdom
- Jianfeng Yu, ; orcid.org/0000-0001-7174-3803
| | - Feng Chen
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Institute for Innovative Development of Food Industry, Shenzhen University, Shenzhen, China
- Feng Chen, ; orcid.org/0000-0002-9054-943X
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10
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Xu ZS, Yang X, Gänzle MG. Resistance of biofilm- and pellicle-embedded strains of Escherichia coli encoding the transmissible locus of stress tolerance (tLST) to oxidative sanitation chemicals. Int J Food Microbiol 2021; 359:109425. [PMID: 34607035 DOI: 10.1016/j.ijfoodmicro.2021.109425] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 09/13/2021] [Accepted: 09/23/2021] [Indexed: 12/11/2022]
Abstract
Biofilm formation in food processing plants reduces the efficacy of sanitation. The presence of transmissible locus of stress tolerance (tLST) also enhances resistance of planktonic cells of Escherichia coli to sanitation chemicals but the role of tLST in resistance of biofilm-embedded cells remains unclear. This study investigated the link of tLST to biofilm formation and its contribution to resistance of biofilm-embedded E. coli to sanitation. Biofilms were formed as single-strain and as dual-strain biofilms in association with E. coli, Aeromonas australensis or Carnobacterium maltaromaticum. Biofilms on stainless steel were compared to floating biofilms formed at the air-liquid interface (pellicles). The resistance of biofilm-embedded tLST positive strains of E. coli to chlorine, hydrogen peroxide, and peroxyacetic acid was higher than the resistance of tLST negative strains. Higher biofilm density as measured by crystal violet staining was observed in tLST-positive strains of E. coli when compared to tLST negative strains. Biofilm density positively correlated to resistance to disinfectants. The use of confocal laser scanning microscopy detected more compact structure of pellicles compared to solid surface-attached biofilms, resulting in higher chlorine resistance despite the absence of tLST in strains of E. coli. Collectively, the findings of this study elucidated the impact of tLST in strains of E. coli on biofilm formation and sanitizer resistance. These findings may inform the development of improved sanitization protocols for food facilities.
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Affiliation(s)
- Zhaohui S Xu
- University of Alberta, Dept. of Agricultural, Food and Nutritional Science, Edmonton, AB, Canada
| | - Xianqin Yang
- Agriculture and Agri-Food Canada, Lacombe Research and Development Centre, 6000 C and E Trail, Lacombe T4L 1W1, AB, Canada
| | - Michael G Gänzle
- University of Alberta, Dept. of Agricultural, Food and Nutritional Science, Edmonton, AB, Canada.
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11
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Abstract
The transcriptomes of Pseudomonas aeruginosa clone C isolates NN2 and SG17M during the mid-exponential and early stationary phase of planktonic growth were evaluated by direct RNA sequencing on the nanopore platform and compared with established short-read cDNA sequencing on the Illumina platform. Fifty to ninety percent of the sense RNAs turned out to be rRNA molecules followed by similar proportions of mRNA transcripts and non-coding RNAs. Both platforms detected similar proportions of uncharged tRNAs and 29 yet undescribed antisense tRNAs. For example, the rarest arginine codon was paired with the most abundant tRNAArg, and the tRNAArg gene is missing for the most frequent arginine codon. More than 90% of the antisense RNA molecules were complementary to a coding sequence. The antisense RNAs were evenly distributed in the genomes. Direct RNA sequencing identified more than 4,000 distinct non-overlapping antisense RNAs during exponential and stationary growth. Besides highly expressed small antisense RNAs less than 200 bases in size, a population of longer antisense RNAs was sequenced that covered a broad range of a few hundred to thousands of bases and could be complementary to a contig of several genes. In summary, direct RNA sequencing identified yet undescribed RNA molecules and an unexpected composition of the pools of tRNAs, sense and antisense RNAs. IMPORTANCE Genome-wide gene expression of bacteria is commonly studied by high-throughput sequencing of size-selected cDNA fragment libraries of reverse-transcribed RNA preparations. However, the depletion of ribosomal RNAs, enzymatic reverse transcription and the fragmentation, size selection and amplification during library preparation lead to inevitable losses of information about the initial composition of the RNA pool. We demonstrate that direct RNA sequencing on the nanopore platform can overcome these limitations. Nanopore sequencing of total RNA yielded novel insights into the Pseudomonas aeruginosa transcriptome that - if replicated in other species - will change our view of the bacterial RNA world. The discovery of sense - antisense pairs of tmRNA, tRNAs and mRNAs indicates a further and unknown level of gene regulation in bacteria.
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12
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Ma Y, Zhang Y, Chen K, Zhang L, Zhang Y, Wang X, Xia X. The role of PhoP/PhoQ two component system in regulating stress adaptation in Cronobacter sakazakii. Food Microbiol 2021; 100:103851. [PMID: 34416955 DOI: 10.1016/j.fm.2021.103851] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 05/30/2021] [Accepted: 06/03/2021] [Indexed: 01/06/2023]
Abstract
Cronobacter sakazakii is an opportunistic foodborne bacterial pathogen that shows resistance to multiple stress conditions. The PhoP/PhoQ two component system is a key regulatory mechanism of stress response and virulence in various bacteria, but its role in C. sakazakii has not been thoroughly studied. In this study, we found the PhoP/PhoQ system in C. sakazakii ATCC BAA-894 enhanced bacterial growth in conditions with low Mg2+, acid pH, and the presence of polymyxin B. Moreover, the ΔphoPQ strain significantly reduced survival following exposure to heat, high osmotic pressure, oxidative or bile salts compared with WT strain. Furthermore, the RNA-seq analysis indicated that 1029 genes were upregulated and 979 genes were downregulated in ΔphoPQ strain. The bacterial secretion system, flagella assembly, beta-Lactam resistance and two-component system pathways were significantly downregulated, while the ABC transporters and microbial metabolism in diverse environments pathways were upregulated. qRT-PCR analysis further confirmed that twelve genes associated with stress tolerance were positively regulated by the PhoP/PhoQ system. Therefore, these findings suggest that the PhoP/PhoQ system is an important regulatory mechanism for C. sakazakii to resist various environmental stress.
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Affiliation(s)
- Yan Ma
- College of Food Science and Engineering, Sino-US Joint Research Center, Northwest A&F University, Shaanxi, 712100, China
| | - Yingying Zhang
- College of Food Science and Engineering, Sino-US Joint Research Center, Northwest A&F University, Shaanxi, 712100, China
| | - Ke Chen
- College of Food Science and Engineering, Sino-US Joint Research Center, Northwest A&F University, Shaanxi, 712100, China
| | - Lingzhu Zhang
- College of Food Science and Engineering, Sino-US Joint Research Center, Northwest A&F University, Shaanxi, 712100, China
| | - Yibei Zhang
- College of Food Science and Engineering, Sino-US Joint Research Center, Northwest A&F University, Shaanxi, 712100, China
| | - Xin Wang
- College of Food Science and Engineering, Sino-US Joint Research Center, Northwest A&F University, Shaanxi, 712100, China
| | - Xiaodong Xia
- College of Food Science and Engineering, Sino-US Joint Research Center, Northwest A&F University, Shaanxi, 712100, China; School of Food Science and Technology, National Engineering Research Center of Seafood, Dalian Polytechnic University, 1 Qinggongyuan, Ganjingzi District, Dalian, Liaoning, 116034, China.
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13
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Ecology and Function of the Transmissible Locus of Stress Tolerance in Escherichia coli and Plant-Associated Enterobacteriaceae. mSystems 2021; 6:e0037821. [PMID: 34402641 PMCID: PMC8407380 DOI: 10.1128/msystems.00378-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The transmissible locus of stress tolerance (tLST) is a genomic island which confers resistance to heat and chlorine. In this study, we determined that the tLST is frequent in genomes of those Enterobacteriaceae that occur in association with plants as well as the intestines of humans and animals and are relevant as nosocomial pathogens, e.g., Klebsiella and Cronobacter species. The tLST is more frequent in environmental and clinical isolates of Klebsiella pneumoniae than in animal isolates, and heat and chlorine resistance of tLST-positive strains of K. pneumoniae matched the resistance of tLST-positive strains of Escherichia coli. The function of 13 tLST genes was determined by assessing the heat and chlorine resistance of E. coli MG1655 mutants. The deletion of sHsp20, clpKGI, sHspGI, pscA, pscB, and hdeDGI reduced both heat and chlorine resistance; deletion of kefB reduced only chlorine resistance. Genes coding for heat shock proteins sHsp20, clpKGI, and sHspGI decreased the oxidation of cytoplasmic proteins, while kefB decreased the oxidation of membrane lipids. The fitness cost of the tLST for E. coli MG1655 was assessed by pairwise competition experiments with isogenic tLST-positive or tLST-negative strains. The tLST imposes a fitness cost that is compensated for by frequent and lethal challenges with chlorine. All core genes need to be present to maintain the ecological advantage relative to the fitness cost. Taken together, core tLST genes are necessary to provide protection for E. coli against heat and chlorine stress, and the selective pressure for the tLST maintains core genes. IMPORTANCE The transmissible locus of stress tolerance (tLST) is a genomic island comprising 10 core genes that occurs in diverse Enterobacteriaceae and confers resistance to heat and chlorine. Experimentation described in the manuscript describes the physiological function of the core genes by characterization of the resistance of 13 single-knockout (KO) mutants and by characterization of protein and membrane oxidation in these strains after chlorine challenge. Results identify tLST resistance as a genomic island that is specific for those Enterobacteriaceae that occur in plant-associated habitats as well in the intestines of vertebrates. In addition, the ecological function of the genomic island was characterized by large-scale genomic analysis and competition experiments of wild-type and mutant strains. Results suggest that tLST-mediated resistance to chlorine may contribute to the persistence of nosocomial pathogens in hospitals.
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14
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Kamal SM, Simpson DJ, Wang Z, Gänzle M, Römling U. Horizontal Transmission of Stress Resistance Genes Shape the Ecology of Beta- and Gamma-Proteobacteria. Front Microbiol 2021; 12:696522. [PMID: 34295324 PMCID: PMC8290217 DOI: 10.3389/fmicb.2021.696522] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 06/07/2021] [Indexed: 01/25/2023] Open
Abstract
The transmissible locus of stress tolerance (tLST) is found mainly in beta- and gamma-Proteobacteria and confers tolerance to elevated temperature, pressure, and chlorine. This genomic island, previously referred to as transmissible locus of protein quality control or locus of heat resistance likely originates from an environmental bacterium thriving in extreme habitats, but has been widely transmitted by lateral gene transfer. Although highly conserved, the gene content on the island is subject to evolution and gene products such as small heat shock proteins are present in several functionally distinct sequence variants. A number of these genes are xenologs of core genome genes with the gene products to widen the substrate spectrum and to be highly (complementary) expressed thus their functionality to become dominant over core genome genes. In this review, we will present current knowledge of the function of core tLST genes and discuss current knowledge on selection and counter-selection processes that favor maintenance of the tLST island, with frequent acquisition of gene products involved in cyclic di-GMP signaling, in different habitats from the environment to animals and plants, processed animal and plant products, man-made environments, and subsequently humans.
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Affiliation(s)
- Shady Mansour Kamal
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
| | - David J Simpson
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Zhiying Wang
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Michael Gänzle
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Ute Römling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
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15
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Ivanova A, Ghifari AS, Berkowitz O, Whelan J, Murcha MW. The mitochondrial AAA protease FTSH3 regulates Complex I abundance by promoting its disassembly. PLANT PHYSIOLOGY 2021; 186:599-610. [PMID: 33616659 PMCID: PMC8154063 DOI: 10.1093/plphys/kiab074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 01/28/2021] [Indexed: 06/02/2023]
Abstract
ATP is generated in mitochondria by oxidative phosphorylation. Complex I (NADH:ubiquinone oxidoreductase or NADH dehydrogenase) is the first multisubunit protein complex of this pathway, oxidizing NADH and transferring electrons to the ubiquinone pool. Typically, Complex I mutants display a slow growth rate compared to wild-type plants. Here, using a forward genetic screen approach for restored growth of a Complex I mutant, we have identified the mitochondrial ATP-dependent metalloprotease, Filamentous Temperature Sensitive H 3 (FTSH3), as a factor that is required for the disassembly of Complex I. An ethyl methanesulfonate-induced mutation in FTSH3, named as rmb1 (restoration of mitochondrial biogenesis 1), restored Complex I abundance and plant growth. Complementation could be achieved with FTSH3 lacking proteolytic activity, suggesting the unfoldase function of FTSH3 has a role in Complex I disassembly. The introduction of the rmb1 to an additional, independent, and extensively characterized Complex I mutant, ndufs4, resulted in similar increases to Complex I abundance and a partial restoration of growth. These results show that disassembly or degradation of Complex I plays a role in determining its steady-state abundance and thus turnover may vary under different conditions.
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Affiliation(s)
- Aneta Ivanova
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, Perth 6009, Australia
- The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Perth 6009, Australia
| | - Abi S Ghifari
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, Perth 6009, Australia
- The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Perth 6009, Australia
| | - Oliver Berkowitz
- Department of Animal, Plant and Soil Science, School of Life Science, The ARC Centre of Excellence in Plant Energy Biology, La Trobe University, Bundoora 3086, Vic, Australia
| | - James Whelan
- Department of Animal, Plant and Soil Science, School of Life Science, The ARC Centre of Excellence in Plant Energy Biology, La Trobe University, Bundoora 3086, Vic, Australia
| | - Monika W Murcha
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, Perth 6009, Australia
- The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Perth 6009, Australia
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16
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Lee C, Klockgether J, Fischer S, Trcek J, Tümmler B, Römling U. Why? - Successful Pseudomonas aeruginosa clones with a focus on clone C. FEMS Microbiol Rev 2021; 44:740-762. [PMID: 32990729 PMCID: PMC7685784 DOI: 10.1093/femsre/fuaa029] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 07/12/2020] [Indexed: 12/20/2022] Open
Abstract
The environmental species Pseudomonas aeruginosa thrives in a variety of habitats. Within the epidemic population structure of P. aeruginosa, occassionally highly successful clones that are equally capable to succeed in the environment and the human host arise. Framed by a highly conserved core genome, individual members of successful clones are characterized by a high variability in their accessory genome. The abundance of successful clones might be funded in specific features of the core genome or, although not mutually exclusive, in the variability of the accessory genome. In clone C, one of the most predominant clones, the plasmid pKLC102 and the PACGI-1 genomic island are two ubiquitous accessory genetic elements. The conserved transmissible locus of protein quality control (TLPQC) at the border of PACGI-1 is a unique horizontally transferred compository element, which codes predominantly for stress-related cargo gene products such as involved in protein homeostasis. As a hallmark, most TLPQC xenologues possess a core genome equivalent. With elevated temperature tolerance as a characteristic of clone C strains, the unique P. aeruginosa and clone C specific disaggregase ClpG is a major contributor to tolerance. As other successful clones, such as PA14, do not encode the TLPQC locus, ubiquitous denominators of success, if existing, need to be identified.
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Affiliation(s)
- Changhan Lee
- Department of Microbiology, Tumor and Cell Biology, Biomedicum C8, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Jens Klockgether
- Clinic for Paediatric Pneumology, Allergology and Neonatology, Clinical Research Group 'Pseudomonas Genomics', Hannover Medical School, D-30625 Hannover, Germany
| | - Sebastian Fischer
- Clinic for Paediatric Pneumology, Allergology and Neonatology, Clinical Research Group 'Pseudomonas Genomics', Hannover Medical School, D-30625 Hannover, Germany
| | - Janja Trcek
- Faculty of Natural Sciences and Mathematics, Department of Biology, University of Maribor, Maribor, 2000, Slovenia
| | - Burkhard Tümmler
- Clinic for Paediatric Pneumology, Allergology and Neonatology, Clinical Research Group 'Pseudomonas Genomics', Hannover Medical School, D-30625 Hannover, Germany
| | - Ute Römling
- Department of Microbiology, Tumor and Cell Biology, Biomedicum C8, Karolinska Institutet, SE-171 77 Stockholm, Sweden
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17
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Heywood A, Lamont IL. Cell envelope proteases and peptidases of Pseudomonas aeruginosa: multiple roles, multiple mechanisms. FEMS Microbiol Rev 2020; 44:857-873. [PMID: 32804218 DOI: 10.1093/femsre/fuaa036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Accepted: 08/05/2020] [Indexed: 12/15/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative bacterium that is commonly isolated from damp environments. It is also a major opportunistic pathogen, causing a wide range of problematic infections. The cell envelope of P. aeruginosa, comprising the cytoplasmic membrane, periplasmic space, peptidoglycan layer and outer membrane, is critical to the bacteria's ability to adapt and thrive in a wide range of environments. Over 40 proteases and peptidases are located in the P. aeruginosa cell envelope. These enzymes play many crucial roles. They are required for protein secretion out of the cytoplasm to the periplasm, outer membrane, cell surface or the environment; for protein quality control and removal of misfolded proteins; for controlling gene expression, allowing adaptation to environmental changes; for modification and remodelling of peptidoglycan; and for metabolism of small molecules. The key roles of cell envelope proteases in ensuring normal cell functioning have prompted the development of inhibitors targeting some of these enzymes as potential new anti-Pseudomonas therapies. In this review, we summarise the current state of knowledge across the breadth of P. aeruginosa cell envelope proteases and peptidases, with an emphasis on recent findings, and highlight likely future directions in their study.
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Affiliation(s)
- Astra Heywood
- Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand
| | - Iain L Lamont
- Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand
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18
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Dadfarma N, Karimi G, Nowroozi J, Nejadi N, Kazemi B, Bandehpour M. Proteomic analysis of Lactobacillus casei in response to different pHs using two-dimensional electrophoresis and MALDI TOF mass spectroscopy. IRANIAN JOURNAL OF MICROBIOLOGY 2020; 12:431-436. [PMID: 33603998 PMCID: PMC7867702 DOI: 10.18502/ijm.v12i5.4604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Background and Objectives: Lactobacillus casei, an acid-resistant bacterium, has a protective role against the pathogens. So we aimed to determine the proteome of Lactobacillus casei ATCC39392 strain in response to different pHs of 5 and 7 using proteomic analysis. Materials and Methods: Supernatant and bacterial extraction of Lactobacillus casei ATCC39392 adapts at pHs 5 and 7 were isolated using sodium dodecyl sulfate–polyacrylamide gel and two-dimensional gel electrophoresis. The comparison of results showed that 7 protein spots were seen in pH 5 but not in pH 7. Afterward, they were excised and sent for Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) to be identified. Results: Seven different proteins (four secretory and three structural) with different roles in human body health were identified. Prescribed proteins include putative cell wall associated Hydrolase, Glycoside Hydrolase, beta-N-Acetyl hexosaminidase, Histidine Kinase, Chaperonin, metal dependent Hydrolase and Lysozyme. Conclusion: Seven isolated proteins with anti-cancer and digestive impresses are proper subjects in therapy or drug delivery approaches especially oral drug usage for protection against stomach acidic area.
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Affiliation(s)
- Narges Dadfarma
- Department of Microbiology, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Golgis Karimi
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Jamileh Nowroozi
- Department of Microbiology, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Naser Nejadi
- Proteomics Research Center, School of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Bahram Kazemi
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mojgan Bandehpour
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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