1
|
Niu H, Gu J, Zhang Y. Bacterial persisters: molecular mechanisms and therapeutic development. Signal Transduct Target Ther 2024; 9:174. [PMID: 39013893 PMCID: PMC11252167 DOI: 10.1038/s41392-024-01866-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Revised: 05/06/2024] [Accepted: 05/13/2024] [Indexed: 07/18/2024] Open
Abstract
Persisters refer to genetically drug susceptible quiescent (non-growing or slow growing) bacteria that survive in stress environments such as antibiotic exposure, acidic and starvation conditions. These cells can regrow after stress removal and remain susceptible to the same stress. Persisters are underlying the problems of treating chronic and persistent infections and relapse infections after treatment, drug resistance development, and biofilm infections, and pose significant challenges for effective treatments. Understanding the characteristics and the exact mechanisms of persister formation, especially the key molecules that affect the formation and survival of the persisters is critical to more effective treatment of chronic and persistent infections. Currently, genes related to persister formation and survival are being discovered and confirmed, but the mechanisms by which bacteria form persisters are very complex, and there are still many unanswered questions. This article comprehensively summarizes the historical background of bacterial persisters, details their complex characteristics and their relationship with antibiotic tolerant and resistant bacteria, systematically elucidates the interplay between various bacterial biological processes and the formation of persister cells, as well as consolidates the diverse anti-persister compounds and treatments. We hope to provide theoretical background for in-depth research on mechanisms of persisters and suggest new ideas for choosing strategies for more effective treatment of persistent infections.
Collapse
Affiliation(s)
- Hongxia Niu
- School of Basic Medical Science and Key Laboratory of Blood-stasis-toxin Syndrome of Zhejiang Province, Zhejiang Chinese Medical University, Hangzhou, 310053, Zhejiang, China
| | - Jiaying Gu
- School of Basic Medical Science and Key Laboratory of Blood-stasis-toxin Syndrome of Zhejiang Province, Zhejiang Chinese Medical University, Hangzhou, 310053, Zhejiang, China
| | - Ying Zhang
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, 310003, Zhejiang, China.
- Jinan Microecological Biomedicine Shandong Laboratory, Jinan, 250022, Shandong, China.
| |
Collapse
|
2
|
Karimaei S, Aghamir SMK, Pourmand MR. Comparative analysis of genes expression involved in type II toxin-antitoxin system in Staphylococcus aureus following persister cell formation. Mol Biol Rep 2024; 51:324. [PMID: 38393536 DOI: 10.1007/s11033-023-09179-6] [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: 07/23/2023] [Accepted: 12/18/2023] [Indexed: 02/25/2024]
Abstract
BACKGROUND The formation of persister cells is the main reason for persistent infections. They are associated with antibiotic treatment failure and subsequently chronic infection. The study aimed to assess the expression of type II toxin/antitoxin (TA) system genes in persister cells of Staphylococcus aureus in the presence of the following antibiotics vancomycin, ciprofloxacin, and gentamicin in exponential and stationary phases. METHODS AND RESULTS The colony count was used to evaluate the effect of different types of antibiotics on S. aureus persister cell formation during exponential and stationary phases. Moreover, the expression level of TA systems and clpP genes in the persister population in exponential and stationary phases were measured by quantitative reverse transcriptase real-time PCR (qRT-PCR). The results of the study showed the presence of persister phenotype of S. aureus strains in the attendance of bactericidal antibiotics in comparison to the control group during the exponential and stationary phases. Moreover, qRT-PCR resulted in the fact that the role of TA systems involved in the persister cell formation depends on the bacterial growth phase and the type of strain and antibiotic. CONCLUSIONS In total, the present study provides some data on the persister cell formation and the possible role of TA system genes in this process.
Collapse
Affiliation(s)
- Samira Karimaei
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Mohammad Reza Pourmand
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
- Department of Pathobiology, School of Public Health and Biotechnology Research Center, Tehran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
3
|
Bogut A, Koper P, Marczak M, Całka P. The first genomic characterization of a stable, hemin-dependent small colony variant strain of Staphylococcus epidermidis isolated from a prosthetic-joint infection. Front Microbiol 2023; 14:1289844. [PMID: 37928677 PMCID: PMC10620731 DOI: 10.3389/fmicb.2023.1289844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Accepted: 10/05/2023] [Indexed: 11/07/2023] Open
Abstract
Phenotype switching from a wild type (WT) to a slow-growing subpopulation, referred to as small colony variants (SCVs), supports an infectious lifestyle of Staphylococcus epidermidis, the leading cause of medical device-related infections. Specific mechanisms underlying formation of SCVs and involved in the shaping of their pathogenic potential are of particular interest for stable strains as they have been only rarely cultured from clinical specimens. As the SCV phenotype stability implies the existence of genetic changes, the whole genome sequence of a stable, hemin-dependent S. epidermidis SCV strain (named 49SCV) involved in a late prosthetic joint infection was analyzed. The strain was isolated in a monoculture without a corresponding WT clone, therefore, its genome was compared against five reference S. epidermidis strains (ATCC12228, ATCC14990, NBRC113846, O47, and RP62A), both at the level of the genome structure and coding sequences. According to the Multilocus Sequence Typing analysis, the 49SCV strain represented the sequence type 2 (ST2) regarded as the most prominent infection-causing lineage with a worldwide dissemination. Genomic features unique to 49SCV included the absence of the Staphylococcal Cassette Chromosome (SCC), ~12 kb deletion with the loss of genes involved in the arginine deiminase pathway, and frameshift-generating mutations within the poly(A) and poly(T) homopolymeric tracts. Indels were identified in loci associated with adherence, metabolism, stress response, virulence, and cell wall synthesis. Of note, deletion in the poly(A) of the hemA gene has been considered a possible trigger factor for the phenotype transition and hemin auxotrophy in the strain. To our knowledge, the study represents the first genomic characterization of a clinical, stable and hemin-dependent S. epidermidis SCV strain. We propose that previously unreported indels in the homopolymeric tracts can constitute a background of the SCV phenotype due to a resulting truncation of the corresponding proteins and their possible biological dysfunction. Streamline of genetic content evidenced by the loss of the SCC and a large genomic deletion can represent a possible strategy associated both with the SCV phenotype and its adaptation to chronicity.
Collapse
Affiliation(s)
- Agnieszka Bogut
- Chair and Department of Medical Microbiology, Medical University of Lublin, Lublin, Poland
| | - Piotr Koper
- Department of Genetics and Microbiology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Lublin, Poland
| | - Małgorzata Marczak
- Department of Genetics and Microbiology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Lublin, Poland
| | - Paulina Całka
- Chair and Department of Forensic Medicine, Medical University of Lublin, Lublin, Poland
| |
Collapse
|
4
|
Pizzolato-Cezar LR, Spira B, Machini MT. Bacterial toxin-antitoxin systems: Novel insights on toxin activation across populations and experimental shortcomings. CURRENT RESEARCH IN MICROBIAL SCIENCES 2023; 5:100204. [PMID: 38024808 PMCID: PMC10643148 DOI: 10.1016/j.crmicr.2023.100204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023] Open
Abstract
The alarming rise in hard-to-treat bacterial infections is of great concern to human health. Thus, the identification of molecular mechanisms that enable the survival and growth of pathogens is of utmost urgency for the development of more efficient antimicrobial therapies. In challenging environments, such as presence of antibiotics, or during host infection, metabolic adjustments are essential for microorganism survival and competitiveness. Toxin-antitoxin systems (TASs) consisting of a toxin with metabolic modulating activity and a cognate antitoxin that antagonizes that toxin are important elements in the arsenal of bacterial stress defense. However, the exact physiological function of TA systems is highly debatable and with the exception of stabilization of mobile genetic elements and phage inhibition, other proposed biological functions lack a broad consensus. This review aims at gaining new insights into the physiological effects of TASs in bacteria and exploring the experimental shortcomings that lead to discrepant results in TAS research. Distinct control mechanisms ensure that only subsets of cells within isogenic cultures transiently develop moderate levels of toxin activity. As a result, TASs cause phenotypic growth heterogeneity rather than cell stasis in the entire population. It is this feature that allows bacteria to thrive in diverse environments through the creation of subpopulations with different metabolic rates and stress tolerance programs.
Collapse
Affiliation(s)
- Luis R. Pizzolato-Cezar
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Beny Spira
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - M. Teresa Machini
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
5
|
Li Y, Zhu F, Manna AC, Chen L, Jiang J, Hong JI, Proctor RA, Bayer AS, Cheung AL, Xiong YQ. Gp05, a Prophage-Encoded Virulence Factor, Contributes to Persistent Methicillin-Resistant Staphylococcus aureus Endovascular Infection. Microbiol Spectr 2023; 11:e0060023. [PMID: 37358448 PMCID: PMC10434118 DOI: 10.1128/spectrum.00600-23] [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: 02/08/2023] [Accepted: 05/24/2023] [Indexed: 06/27/2023] Open
Abstract
Persistent methicillin-resistant Staphylococcus aureus (MRSA) endovascular infections represent a serious public health threat. We recently demonstrated that the presence of a novel prophage ϕSA169 was associated with vancomycin (VAN) treatment failure in experimental MRSA endocarditis. In this study, we assessed the role of a ϕSA169 gene, ϕ80α_gp05 (gp05), in VAN-persistent outcome using gp05 isogenic MRSA strain sets. Of note, Gp05 significantly influences the intersection of MRSA virulence factors, host immune responses, and antibiotic treatment efficacy, including the following: (i) activity of the significant energy-yielding metabolic pathway (e.g., tricarboxylic acid cycle); (ii) carotenoid pigment production; (iii) (p)ppGpp (guanosine tetra- and pentaphosphate) production, which activates the stringent response and subsequent downstream functional factors (e.g., phenol-soluble modulins and polymorphonuclear neutrophil bactericidal activity); and (iv) persistence to VAN treatment in an experimental infective endocarditis model. These data suggest that Gp05 is a significant virulence factor which contributes to the persistent outcomes in MRSA endovascular infection by multiple pathways. IMPORTANCE Persistent endovascular infections are often caused by MRSA strains that are susceptible to anti-MRSA antibiotics in vitro by CLSI breakpoints. Thus, the persistent outcome represents a unique variant of traditional antibiotic resistance mechanisms and a significant therapeutic challenge. Prophage, a critical mobile genetic element carried by most MRSA isolates, provides their bacterial host with metabolic advantages and resistance mechanisms. However, how prophage-encoded virulence factors interact with the host defense system and antibiotics, driving the persistent outcome, is not well known. In the current study, we demonstrated that a novel prophage gene, gp05, significantly impacts tricarboxylic acid cycle activity, stringent response, and pigmentation, as well as vancomycin treatment outcome in an experimental endocarditis model using isogenic gp05 overexpression and chromosomal deletion mutant MRSA strain sets. The findings significantly advance our understanding of the role of Gp05 in persistent MRSA endovascular infection and provide a potential target for development of novel drugs against these life-threatening infections.
Collapse
Affiliation(s)
- Yi Li
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
| | - Fengli Zhu
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
| | - Adhar C. Manna
- Department of Microbiology & Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Liang Chen
- Center for Discovery and Innovation, Nutley, New Jersey, USA
| | - Jason Jiang
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
| | - Jong-In Hong
- Department of Chemistry, Seoul National University, Seoul, South Korea
| | - Richard A. Proctor
- Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Arnold S. Bayer
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
- David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Ambrose L. Cheung
- Department of Microbiology & Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Yan Q. Xiong
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
- David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| |
Collapse
|
6
|
Can H, Chanumolu SK, Nielsen BD, Alvarez S, Naldrett MJ, Ünlü G, Otu HH. Integration of Meta-Multi-Omics Data Using Probabilistic Graphs and External Knowledge. Cells 2023; 12:1998. [PMID: 37566077 PMCID: PMC10417344 DOI: 10.3390/cells12151998] [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: 05/12/2023] [Revised: 07/11/2023] [Accepted: 08/02/2023] [Indexed: 08/12/2023] Open
Abstract
Multi-omics has the promise to provide a detailed molecular picture of biological systems. Although obtaining multi-omics data is relatively easy, methods that analyze such data have been lagging. In this paper, we present an algorithm that uses probabilistic graph representations and external knowledge to perform optimal structure learning and deduce a multifarious interaction network for multi-omics data from a bacterial community. Kefir grain, a microbial community that ferments milk and creates kefir, represents a self-renewing, stable, natural microbial community. Kefir has been shown to have a wide range of health benefits. We obtained a controlled bacterial community using the two most abundant and well-studied species in kefir grains: Lentilactobacillus kefiri and Lactobacillus kefiranofaciens. We applied growth temperatures of 30 °C and 37 °C and obtained transcriptomic, metabolomic, and proteomic data for the same 20 samples (10 samples per temperature). We obtained a multi-omics interaction network, which generated insights that would not have been possible with single-omics analysis. We identified interactions among transcripts, proteins, and metabolites, suggesting active toxin/antitoxin systems. We also observed multifarious interactions that involved the shikimate pathway. These observations helped explain bacterial adaptation to different stress conditions, co-aggregation, and increased activation of L. kefiranofaciens at 37 °C.
Collapse
Affiliation(s)
- Handan Can
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Sree K. Chanumolu
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Barbara D. Nielsen
- Department of Animal, Veterinary and Food Sciences, University of Idaho, Moscow, ID 83844, USA
| | - Sophie Alvarez
- Proteomics and Metabolomics Facility, Nebraska Center for Biotechnology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Michael J. Naldrett
- Proteomics and Metabolomics Facility, Nebraska Center for Biotechnology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Gülhan Ünlü
- Department of Animal, Veterinary and Food Sciences, University of Idaho, Moscow, ID 83844, USA
- Department of Chemical and Biological Engineering, University of Idaho, Moscow, ID 83844, USA
- School of Food Science, Washington State University, Pullman, WA 99164, USA
| | - Hasan H. Otu
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| |
Collapse
|
7
|
Aljghami ME, Barghash MM, Majaesic E, Bhandari V, Houry WA. Cellular functions of the ClpP protease impacting bacterial virulence. Front Mol Biosci 2022; 9:1054408. [PMID: 36533084 PMCID: PMC9753991 DOI: 10.3389/fmolb.2022.1054408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 11/15/2022] [Indexed: 09/28/2023] Open
Abstract
Proteostasis mechanisms significantly contribute to the sculpting of the proteomes of all living organisms. ClpXP is a central AAA+ chaperone-protease complex present in both prokaryotes and eukaryotes that facilitates the unfolding and subsequent degradation of target substrates. ClpX is a hexameric unfoldase ATPase, while ClpP is a tetradecameric serine protease. Substrates of ClpXP belong to many cellular pathways such as DNA damage response, metabolism, and transcriptional regulation. Crucially, disruption of this proteolytic complex in microbes has been shown to impact the virulence and infectivity of various human pathogenic bacteria. Loss of ClpXP impacts stress responses, biofilm formation, and virulence effector protein production, leading to decreased pathogenicity in cell and animal infection models. Here, we provide an overview of the multiple critical functions of ClpXP and its substrates that modulate bacterial virulence with examples from several important human pathogens.
Collapse
Affiliation(s)
- Mazen E. Aljghami
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Marim M. Barghash
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Emily Majaesic
- Department of Chemistry, University of Toronto, Toronto, ON, Canada
| | - Vaibhav Bhandari
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Walid A. Houry
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
- Department of Chemistry, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
8
|
Cervimycin-Resistant Staphylococcus aureus Strains Display Vancomycin-Intermediate Resistant Phenotypes. Microbiol Spectr 2022; 10:e0256722. [PMID: 36173303 PMCID: PMC9603734 DOI: 10.1128/spectrum.02567-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Resistance to antibiotics is an increasing problem and necessitates novel antibacterial therapies. The polyketide antibiotics cervimycin A to D are natural products of Streptomyces tendae HKI 0179 with promising activity against multidrug-resistant staphylococci and vancomycin-resistant enterococci. To initiate mode of action studies, we selected cervimycin C- and D-resistant (CmR) Staphylococcus aureus strains. Genome sequencing of CmR mutants revealed amino acid exchanges in the essential histidine kinase WalK, the Clp protease proteolytic subunit ClpP or the Clp ATPase ClpC, and the heat shock protein DnaK. Interestingly, all characterized CmR mutants harbored a combination of mutations in walK and clpP or clpC. In vitro and in vivo analyses showed that the mutations in the Clp proteins abolished ClpP or ClpC activity, and the deletion of clpP rendered S. aureus but not all Bacillus subtilis strains cervimycin-resistant. The essential gene walK was the second mutational hotspot in the CmR S. aureus strains, which decreased WalK activity in vitro and generated a vancomycin-intermediate resistant phenotype, with a thickened cell wall, a lower growth rate, and reduced cell lysis. Transcriptomic and proteomic analyses revealed massive alterations in the CmR strains compared to the parent strain S. aureus SG511, with major shifts in the heat shock regulon, the metal ion homeostasis, and the carbohydrate metabolism. Taken together, mutations in the heat shock genes clpP, clpC, and dnaK, and the walK kinase gene in CmR mutants induced a vancomycin-intermediate resistant phenotype in S. aureus, suggesting cell wall metabolism or the Clp protease system as primary target of cervimycin. IMPORTANCE Staphylococcus aureus is a frequent cause of infections in both the community and hospital setting. Resistance development of S. aureus to various antibiotics is a severe problem for the treatment of this pathogen worldwide. New powerful antimicrobial agents against Gram-positives are needed, since antibiotics like vancomycin fail to cure vancomycin-intermediate resistant S. aureus (VISA) and vancomycin-resistant enterococci (VRE) infections. One candidate substance with promising activity against these organisms is cervimycin, which is an antibiotic complex with a yet unknown mode of action. In our study, we provide first insights into the mode of action of cervimycins. By characterizing cervimycin-resistant S. aureus strains, we revealed the Clp system and the essential kinase WalK as mutational hotspots for cervimycin resistance in S. aureus. It further emerged that cervimycin-resistant S. aureus strains show a VISA phenotype, indicating a role of cervimycin in perturbing the bacterial cell envelope.
Collapse
|
9
|
Kim M, Kim W, Lee Y, Park W. Linkage between bacterial community-mediated hydrogen peroxide detoxification and the growth of Microcystis aeruginosa. WATER RESEARCH 2021; 207:117784. [PMID: 34731663 DOI: 10.1016/j.watres.2021.117784] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 09/30/2021] [Accepted: 10/13/2021] [Indexed: 06/13/2023]
Abstract
Microcystis aeruginosa, an important cyanobloom-forming cyanobacterium, is sensitive to the high light intensity and consequent oxidative stress. Based on our genomic and transcriptomic analyses of H2O2-treated cells, many genes involved in photosynthesis, Calvin cycle, and microcystin synthesis were downregulated, whereas several toxin-antitoxin genes, DNA repair genes, and H2O2-defense systems such as peroxiredoxins and glutathione synthesis were upregulated. Axenic M. aeruginosa was then co-cultured with synthetic bacterial communities collected from 15 different freshwater samples with exhibiting different degrees of H2O2-production and catalase activities. Our analyses indicated that H2O2-resistant bacterial communities favored the growth and photosynthetic activity of M. aeruginosa cells under either H2O2 treatment or high light conditions. Nanopore-based bacterial community analyses indicated that these growth-promoting effects were likely attributable to a high proportion of Alphaproteobacteria (e.g., Brevundimonas and Ochrobactrum species), which protected M. aeruginosa cells from H2O2 toxicity. Further, these bacterial communities exhibited higher catalase activity levels and faster O2 production rates upon H2O2 detoxification. Taken together, our findings newly suggest that the occurrence of catalase-less M. aeruginosa blooms is largely influenced by the surrounding microbiota during high light and organic-rich conditions.
Collapse
Affiliation(s)
- Minkyung Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Wonjae Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Yunho Lee
- Department of Food Science and Biotechnology, CHA University, Pocheon, Gyeonggi-do 11160, Republic of Korea
| | - Woojun Park
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea.
| |
Collapse
|
10
|
Dong S, Chen H, Zhou Q, Liao N. Protein degradation control and regulation of bacterial survival and pathogenicity: the role of protein degradation systems in bacteria. Mol Biol Rep 2021; 48:7575-7585. [PMID: 34655017 DOI: 10.1007/s11033-021-06744-9] [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: 08/11/2021] [Accepted: 10/01/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Protein degradation systems play crucial roles in all the kingdoms of life. Their natural function is to eliminate proteins that are improperly synthesized, damaged, aggregated, or short-lived, ensuring the timely and accurate regulation of the response to abrupt environmental changes. Thus, proteolysis plays an important role in protein homeostasis, quality control, and the control of regulatory processes, such as adaptation and cell development. Except for the lysosome, ATPases Associated with various cellular Activities (AAA+) ATPase-protease complex is another major protein degradation system in the cell. METHODS AND RESULTS The AAA+ ATPase-protease complex is a giant energy-dependent protease complex found in almost all kinds of cells, including bacteria, archaea and eukarya. Based on sequence analysis of ClpQ (HslV) and 20S proteasome beta subunits, it was found that bacterial ClpQ possess multiple same highly conserved motifs with 20S proteasome beta subunits of archaea and eukaryote. In this review, we also discussed the structure and functional mechanism, protein degradation signals and pathogenic role of proteasome / Clp protease complex in prokaryotes. CONCLUSION Bacterial protein degradation systems play important roles in stress tolerance, protein quality control, DNA protection, transcription and pathogenicity of bacteria. But our current knowledge of the bacterial protease system is incomplete, and further research into the Clp protease complex and associated protein degradation signals will extend our understanding of the metabolism, physiology, reproduction, and pathogenicity of bacteria.
Collapse
Affiliation(s)
- Shilei Dong
- Department of Clinical Laboratory, Zhejiang Hospital, Hangzhou, 310013, China
| | - Honghu Chen
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, 310051, China
| | - Qingxue Zhou
- Department of Clinical Laboratory, Hangzhou Women's Hospital (Hangzhou Maternity and Child Health Care Hospital), Hangzhou, 310008, China
| | - Ningbo Liao
- College of Food Science and Engineering, Jiangxi Agricultural University, Nanchang, 330045, China.
| |
Collapse
|
11
|
Karimaei S, Kalani BS, Shahrokhi N, Mashhadi R, Pourmand MR. Expression of type II toxin-antitoxin systems and ClpP protease of methicillin-resistant Staphylococcus aureus under thermal and oxidative stress conditions. IRANIAN JOURNAL OF MICROBIOLOGY 2021; 13:204-211. [PMID: 34540156 PMCID: PMC8408035 DOI: 10.18502/ijm.v13i2.5982] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Background and Objectives: Staphylococcus aureus is a main human pathogen that causes a variety of chronic to persistent infections. Across the diverse factors of pathogenesis in bacteria, Toxin-Antitoxin (TA) systems can be considered as an anti-bacterial target due to their involvement in cellular physiology counting stress responses. Here, the expression of TA system genes and ClpP protease was investigated under the thermal and oxidative conditions in S. aureus strains. Materials and Methods: The colony-forming unit (CFU) was used to determine the effects of thermal and oxidative stresses on bacterial survival. Moreover, the expressions of TA system genes in S. aureus strains were evaluated 30 min and 1 h after thermal and oxidative stresses, respectively, by quantitative reverse transcriptase real-time PCR (qRT-PCR). Results: The cell viability was constant across thermal stress while oxidative stress induction showed a significantly decrease in the growth of Methicillin-Resistant S. aureus (MRSA) strain. Based on the qRT-PCR results, the expression of mazF gene increased under both thermal and oxidative stresses in the MRSA strain. Conclusion: A putative TA system (namely immA/irrA) most likely has a role under the stress condition of S. aureus. The MRSA strain responds to stress by shifting the expression level of TA genes that has diverse effects on the survival of the pathogen due to the stress conditions. The TA systems may be introduced as potential targets for antibacterial treatment.
Collapse
Affiliation(s)
- Samira Karimaei
- Department of Pathobiology, Biotechnology Research Center, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Behrooz Sadeghi Kalani
- Department of Medical Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran.,Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | - Nader Shahrokhi
- Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran
| | - Rahil Mashhadi
- Urology Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Pourmand
- Department of Pathobiology, Biotechnology Research Center, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
12
|
Illigmann A, Thoma Y, Pan S, Reinhardt L, Brötz-Oesterhelt H. Contribution of the Clp Protease to Bacterial Survival and Mitochondrial Homoeostasis. Microb Physiol 2021; 31:260-279. [PMID: 34438398 DOI: 10.1159/000517718] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 06/07/2021] [Indexed: 11/19/2022]
Abstract
Fast adaptation to environmental changes ensures bacterial survival, and proteolysis represents a key cellular process in adaptation. The Clp protease system is a multi-component machinery responsible for protein homoeostasis, protein quality control, and targeted proteolysis of transcriptional regulators in prokaryotic cells and prokaryote-derived organelles of eukaryotic cells. A functional Clp protease complex consists of the tetradecameric proteolytic core ClpP and a hexameric ATP-consuming Clp-ATPase, several of which can associate with the same proteolytic core. Clp-ATPases confer substrate specificity by recognising specific degradation tags, and further selectivity is conferred by adaptor proteins, together allowing for a fine-tuned degradation process embedded in elaborate regulatory networks. This review focuses on the contribution of the Clp protease system to prokaryotic survival and summarises the current state of knowledge for exemplary bacteria in an increasing degree of interaction with eukaryotic cells. Starting from free-living bacteria as exemplified by a non-pathogenic and a pathogenic member of the Firmicutes, i.e., Bacillus subtilis and Staphylococcus aureus, respectively, we turn our attention to facultative and obligate intracellular bacterial pathogens, i.e., Mycobacterium tuberculosis, Listeria monocytogenes, and Chlamydia trachomatis, and conclude with mitochondria. Under stress conditions, the Clp protease system exerts its pivotal role in the degradation of damaged proteins and controls the timing and extent of the heat-shock response by regulatory proteolysis. Key regulators of developmental programmes like natural competence, motility, and sporulation are also under Clp proteolytic control. In many pathogenic species, the Clp system is required for the expression of virulence factors and essential for colonising the host. In accordance with its evolutionary origin, the human mitochondrial Clp protease strongly resembles its bacterial counterparts, taking a central role in protein quality control and homoeostasis, energy metabolism, and apoptosis in eukaryotic cells, and several cancer cell types depend on it for proliferation.
Collapse
Affiliation(s)
- Astrid Illigmann
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Yvonne Thoma
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Stefan Pan
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Laura Reinhardt
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Heike Brötz-Oesterhelt
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany.,Cluster of Excellence Controlling Microbes to Fight Infection, University of Tübingen, Tübingen, Germany
| |
Collapse
|
13
|
Chebotar' IV, Emelyanova MA, Bocharova JA, Mayansky NA, Kopantseva EE, Mikhailovich VM. The classification of bacterial survival strategies in the presence of antimicrobials. Microb Pathog 2021; 155:104901. [PMID: 33930413 DOI: 10.1016/j.micpath.2021.104901] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 04/05/2021] [Accepted: 04/06/2021] [Indexed: 01/14/2023]
Abstract
The survival of bacteria under antibiotic therapy varies in nature and is based on the bacterial ability to employ a wide range of fundamentally different resistance mechanisms. This great diversity requires a disambiguation of the term 'resistance' and the development of a more precise classification of bacterial survival strategies during contact with antibiotics. The absence of a unified definition for the terms 'resistance', 'tolerance' and 'persistence' further aggravates the imperfections of the current classification system. This review suggests a number of original classification criteria that will take into account (1) the bacterial ability to replicate in the presence of antimicrobial agents, (2) existing evolutionary stability of a trait within a species, and (3) the presence or absence of specialized genes that determine the ability of a microorganism to decrease its own metabolism or switch it completely off. This review describes potential advantages of the suggested classification system, which include a better understanding of the relationship between bacterial survival in the presence of antibiotics and molecular mechanisms of cellular metabolism suppression, the opportunity to pinpoint targets to identify a true bacterial resistance profile. The true resistance profile in turn, could be used to develop effective diagnostic and antimicrobial therapy methods, while taking into consideration specific bacterial survival mechanisms.
Collapse
Affiliation(s)
- Igor V Chebotar'
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilova St., Moscow, 119991, Russian Federation; Pirogov Russian National Research Medical University, 1 Ostrovitianov St., Moscow, 117997, Russian Federation
| | - Marina A Emelyanova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilova St., Moscow, 119991, Russian Federation
| | - Julia A Bocharova
- Pirogov Russian National Research Medical University, 1 Ostrovitianov St., Moscow, 117997, Russian Federation
| | - Nikolay A Mayansky
- Pirogov Russian National Research Medical University, 1 Ostrovitianov St., Moscow, 117997, Russian Federation
| | - Elena E Kopantseva
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilova St., Moscow, 119991, Russian Federation
| | - Vladimir M Mikhailovich
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilova St., Moscow, 119991, Russian Federation.
| |
Collapse
|
14
|
Ju Y, An Q, Zhang Y, Sun K, Bai L, Luo Y. Recent advances in Clp protease modulation to address virulence, resistance and persistence of MRSA infection. Drug Discov Today 2021; 26:2190-2197. [PMID: 34048895 DOI: 10.1016/j.drudis.2021.05.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 04/17/2021] [Accepted: 05/20/2021] [Indexed: 02/05/2023]
Abstract
The Clp protease is an AAA+ protease that executes abnormally folded or malfunctioning proteins, and has an important role in producing virulence factors, forming biofilms or persisters and developing methicillin-resistant Staphylococcus aureus (MRSA). Recent studies showed that Clp protease controls virulence via agr signaling and degrades antitoxins of the toxin-antitoxin system to modulate the formation of persisters and biofilms. In this review, we focus on recent developments concerning the virulence and persistence regulatory pathways and resistance-related mechanism of Clp protease in S. aureus, with an overview of the Clp modulators developed to treat MRSA infection.
Collapse
Affiliation(s)
- Yuan Ju
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China; Sichuan University Library, Sichuan University, Chengdu 610041, China
| | - Qi An
- Public Health Clinical Center of Chengdu, Chengdu 610041, China
| | - Yiwen Zhang
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Ke Sun
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Lang Bai
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China.
| | - Youfu Luo
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China.
| |
Collapse
|
15
|
Bordes P, Genevaux P. Control of Toxin-Antitoxin Systems by Proteases in Mycobacterium Tuberculosis. Front Mol Biosci 2021; 8:691399. [PMID: 34079824 PMCID: PMC8165232 DOI: 10.3389/fmolb.2021.691399] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 05/06/2021] [Indexed: 12/30/2022] Open
Abstract
Toxin-antitoxin (TA) systems are small genetic elements composed of a noxious toxin and a counteracting cognate antitoxin. Although they are widespread in bacterial chromosomes and in mobile genetic elements, their cellular functions and activation mechanisms remain largely unknown. It has been proposed that toxin activation or expression of the TA operon could rely on the degradation of generally less stable antitoxins by cellular proteases. The resulting active toxin would then target essential cellular processes and inhibit bacterial growth. Although interplay between proteases and TA systems has been observed, evidences for such activation cycle are very limited. Herein, we present an overview of the current knowledge on TA recognition by proteases with a main focus on the major human pathogen Mycobacterium tuberculosis, which harbours multiple TA systems (over 80), the essential AAA + stress proteases, ClpC1P1P2 and ClpXP1P2, and the Pup-proteasome system.
Collapse
Affiliation(s)
- Patricia Bordes
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Pierre Genevaux
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, Toulouse, France
| |
Collapse
|
16
|
Bezrukov F, Prados J, Renzoni A, Panasenko OO. MazF toxin causes alterations in Staphylococcus aureus transcriptome, translatome and proteome that underlie bacterial dormancy. Nucleic Acids Res 2021; 49:2085-2101. [PMID: 33544858 PMCID: PMC7913683 DOI: 10.1093/nar/gkaa1292] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/07/2020] [Accepted: 12/28/2020] [Indexed: 12/23/2022] Open
Abstract
Antibiotic resistance is a serious problem which may be caused by bacterial dormancy. It has been suggested that bacterial toxin-antitoxin systems induce dormancy. We analyzed the genome-wide role of Staphylococcus aureus endoribonuclease toxin MazF using RNA-Seq, Ribo-Seq and quantitative proteomics. We characterized changes in transcriptome, translatome and proteome caused by MazF, and proposed that MazF decreases translation directly by cleaving mRNAs, and indirectly, by decreasing translation factors and by promoting ribosome hibernation. Important pathways affected during the early stage of MazF induction were identified: MazF increases cell wall thickness and decreases cell division; MazF activates SsrA-system which rescues stalled ribosomes, appearing as a result of MazF mRNA cleavage. These pathways may be promising targets for new antibacterial drugs that prevent bacteria dormancy. Finally, we described the overall impact of MazF on S. aureus cell physiology, and propose one of the mechanisms by which MazF might regulate cellular changes leading to dormancy.
Collapse
Affiliation(s)
- Fedor Bezrukov
- Department of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK
| | - Julien Prados
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva 1211, Switzerland
| | - Adriana Renzoni
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva 1211, Switzerland.,Division of Infectious Diseases, Department of Medicine, Geneva University Hospitals and Medical School, Geneva 1211, Switzerland
| | - Olesya O Panasenko
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva 1211, Switzerland
| |
Collapse
|
17
|
Srivastava A, Pati S, Kaushik H, Singh S, Garg LC. Toxin-antitoxin systems and their medical applications: current status and future perspective. Appl Microbiol Biotechnol 2021; 105:1803-1821. [PMID: 33582835 DOI: 10.1007/s00253-021-11134-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 01/13/2021] [Accepted: 01/20/2021] [Indexed: 12/11/2022]
Abstract
Almost all bacteria synthesize two types of toxins-one for its survival by regulating different cellular processes and another as a strategy to interact with host cells for pathogenesis. Usually, "bacterial toxins" are contemplated as virulence factors that harm the host organism. However, toxins produced by bacteria, as a survival strategy against the host, also hamper its cellular processes. To overcome this, the bacteria have evolved with the production of a molecule, referred to as antitoxin, to negate the deleterious effect of the toxin against itself. The toxin and antitoxins are encoded by a two-component toxin-antitoxin (TA) system. The antitoxin, a protein or RNA, sequesters the toxins of the TA system for neutralization within the bacterial cell. In this review, we have described different TA systems of bacteria and their potential medical and biotechnological applications. It is of interest to note that while bacterial toxin-antitoxin systems have been well studied, the TA system in unicellular eukaryotes, though predicted by the investigators, have never been paid the desired attention. In the present review, we have also touched upon the TA system of eukaryotes identified to date. KEY POINTS: Bacterial toxins harm the host and also affect the bacterial cellular processes. The antitoxin produced by bacteria protect it from the toxin's harmful effects. The toxin-antitoxin systems can be targeted for various medical applications.
Collapse
Affiliation(s)
- Akriti Srivastava
- Department of Life Sciences, Shiv Nadar University, Gautam Buddha Nagar, Greater Noida, Uttar Pradesh, 201314, India
| | - Soumya Pati
- Department of Life Sciences, Shiv Nadar University, Gautam Buddha Nagar, Greater Noida, Uttar Pradesh, 201314, India
| | - Himani Kaushik
- Gene Regulation Laboratory, National Institute of Immunology, New Delhi, 110067, India
| | - Shailja Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, 110067, India.
| | - Lalit C Garg
- Gene Regulation Laboratory, National Institute of Immunology, New Delhi, 110067, India.
| |
Collapse
|
18
|
Xue L, Yue J, Ke J, Khan MH, Wen W, Sun B, Zhu Z, Niu L. Distinct oligomeric structures of the YoeB-YefM complex provide insights into the conditional cooperativity of type II toxin-antitoxin system. Nucleic Acids Res 2020; 48:10527-10541. [PMID: 32845304 PMCID: PMC7544224 DOI: 10.1093/nar/gkaa706] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 08/07/2020] [Accepted: 08/14/2020] [Indexed: 12/21/2022] Open
Abstract
YoeB-YefM, the widespread type II toxin-antitoxin (TA) module, binds to its own promoter to autoregulate its transcription: repress or induce transcription under normal or stress conditions, respectively. It remains unclear how YoeB-YefM regulates its transcription depending on the YoeB to YefM TA ratio. We find that YoeB-YefM complex from S.aureus exists as two distinct oligomeric assemblies: heterotetramer (YoeB-YefM2-YoeB) and heterohexamer (YoeB-YefM2-YefM2-YoeB) with low and high DNA-binding affinities, respectively. Structures of the heterotetramer alone and heterohexamer bound to promoter DNA reveals that YefM C-terminal domain undergoes disorder to order transition upon YoeB binding, which allosterically affects the conformation of N-terminal DNA-binding domain. At TA ratio of 1:2, unsaturated binding of YoeB to the C-terminal regions of YefM dimer forms an optimal heterohexamer for DNA binding, and two YefM dimers with N-terminal domains dock into the adjacent major grooves of DNA to specifically recognize the 5'-TTGTACAN6AGTACAA-3' palindromic sequence, resulting in transcriptional repression. In contrast, at TA ratio of 1:1, binding of two additional YoeB molecules onto the heterohexamer induces the completely ordered conformation of YefM and disassembles the heterohexamer into two heterotetramers, which are unable to bind the promoter DNA optimally due to steric clashes, hence derepresses TA operon transcription.
Collapse
Affiliation(s)
- Lu Xue
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Molecular and Cellular Biophysics, University of Science and Technology of China, Hefei, Anhui 230026, China.,School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jian Yue
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Molecular and Cellular Biophysics, University of Science and Technology of China, Hefei, Anhui 230026, China.,School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jiyuan Ke
- Lead Discovery Department, H3 Biomedicine Inc, 300 Technology Square FL 5, Cambridge, MA 02139, USA
| | - Muhammad Hidayatullah Khan
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Molecular and Cellular Biophysics, University of Science and Technology of China, Hefei, Anhui 230026, China.,School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Wen Wen
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Baolin Sun
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zhongliang Zhu
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Molecular and Cellular Biophysics, University of Science and Technology of China, Hefei, Anhui 230026, China.,School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Liwen Niu
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Molecular and Cellular Biophysics, University of Science and Technology of China, Hefei, Anhui 230026, China.,School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| |
Collapse
|
19
|
Sierra R, Prados J, Panasenko OO, Andrey DO, Fleuchot B, Redder P, Kelley WL, Viollier PH, Renzoni A. Insights into the global effect on Staphylococcus aureus growth arrest by induction of the endoribonuclease MazF toxin. Nucleic Acids Res 2020; 48:8545-8561. [PMID: 32735661 PMCID: PMC7470975 DOI: 10.1093/nar/gkaa617] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 06/18/2020] [Accepted: 07/27/2020] [Indexed: 12/22/2022] Open
Abstract
A crucial bacterial strategy to avoid killing by antibiotics is to enter a growth arrested state, yet the molecular mechanisms behind this process remain elusive. The conditional overexpression of mazF, the endoribonuclease toxin of the MazEF toxin–antitoxin system in Staphylococcus aureus, is one approach to induce bacterial growth arrest, but its targets remain largely unknown. We used overexpression of mazF and high-throughput sequence analysis following the exact mapping of non-phosphorylated transcriptome ends (nEMOTE) technique to reveal in vivo toxin cleavage sites on a global scale. We obtained a catalogue of MazF cleavage sites and unearthed an extended MazF cleavage specificity that goes beyond the previously reported one. We correlated transcript cleavage and abundance in a global transcriptomic profiling during mazF overexpression. We observed that MazF affects RNA molecules involved in ribosome biogenesis, cell wall synthesis, cell division and RNA turnover and thus deliver a plausible explanation for how mazF overexpression induces stasis. We hypothesize that autoregulation of MazF occurs by directly modulating the MazEF operon, such as the rsbUVW genes that regulate the sigma factor SigB, including an observed cleavage site on the MazF mRNA that would ultimately play a role in entry and exit from bacterial stasis.
Collapse
Affiliation(s)
- Roberto Sierra
- Service of Infectious Diseases, Department of Medical Specialties, Geneva University Hospitals and Medical School, Geneva 1211, Switzerland.,Department of Microbiology and Molecular Medicine, University of Geneva, Geneva 1211, Switzerland
| | - Julien Prados
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva 1211, Switzerland
| | - Olesya O Panasenko
- Service of Infectious Diseases, Department of Medical Specialties, Geneva University Hospitals and Medical School, Geneva 1211, Switzerland
| | - Diego O Andrey
- Service of Infectious Diseases, Department of Medical Specialties, Geneva University Hospitals and Medical School, Geneva 1211, Switzerland.,Department of Microbiology and Molecular Medicine, University of Geneva, Geneva 1211, Switzerland
| | - Betty Fleuchot
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva 1211, Switzerland
| | - Peter Redder
- Centre de Biologie Intégrative, Université de Toulouse III, Toulouse 31400, France
| | - William L Kelley
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva 1211, Switzerland
| | - Patrick H Viollier
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva 1211, Switzerland
| | - Adriana Renzoni
- Service of Infectious Diseases, Department of Medical Specialties, Geneva University Hospitals and Medical School, Geneva 1211, Switzerland.,Department of Microbiology and Molecular Medicine, University of Geneva, Geneva 1211, Switzerland
| |
Collapse
|
20
|
Evaluation of Putative Type II Toxin-Antitoxin Systems and Lon Protease Expression in Shigella flexneri Following Infection of Caco-2 Cells. ARCHIVES OF CLINICAL INFECTIOUS DISEASES 2020. [DOI: 10.5812/archcid.98625] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
: Shigella flexneri causes bacillary dysentery in developing countries. Due to recent reports regarding antimicrobial resistance in human S. flexneri, finding alternative therapeutics is of vital importance. Toxin-antitoxin (TA) systems have recently been introduced as antimicrobial targets owing to their involvement in bacterial survival in stress conditions and “persister” cell formation. In this study, the presence of four TA loci were studied in S. flexneri ATCC 12022. The presence of genes coding for the identified TA loci and Lon protease were confirmed by the PCR method using specific primers. Caco-2 cell lines were then infected with this standard strain, and 8 and 24 h post-infection, expression levels of genes coding for the studied TA loci, and Lon protease were evaluated using a real-time PCR method. Expression of mazF, GNAT (Gcn5-related N-acetyltransferase), yeeU, pfam13975, and Lon genes showed 5.4, 9.8, 2.3, 2.7, and 13.8-fold increase, respectively, 8 h after bacterial invasion of the Caco-2 cell line. In addition, the expression of the aforementioned genes showed 4.8, 10.8, 2.3, 3.7, and 16.8-fold increase after 24 h. The GNAT and lon genes showed significantly higher expression levels compared to the control (P value < 0.05). However, the increase in the expression level of yeeU was the same at 8 h and 24 h post-infection. In addition, mazF expression level showed a slight decrease at 24 h compared to 8h post-infection. Genes coding for GNAT and Lon protease showed a significantly higher expression after invading the Caco-2 cell line. Therefore, targeting GNAT or Lon protease can be taken into consideration for finding novel antimicrobial drug strategies. The exact functions and mechanisms of TA systems in S. flexneri isolates are suggested to be experimentally determined.
Collapse
|
21
|
Cross-Regulations between Bacterial Toxin-Antitoxin Systems: Evidence of an Interconnected Regulatory Network? Trends Microbiol 2020; 28:851-866. [PMID: 32540313 DOI: 10.1016/j.tim.2020.05.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 12/31/2022]
Abstract
Toxin-antitoxin (TA) systems are ubiquitous among bacteria and include stable toxins whose toxicity can be counteracted by RNA or protein antitoxins. They are involved in multiple functions that range from stability maintenance for mobile genetic elements to stress adaptation. Bacterial chromosomes frequently have multiple homologues of TA system loci, and it is unclear why there are so many of them. In this review we focus on cross-regulations between TA systems, which occur between both homologous and nonhomologous systems, from similar or distinct types, whether encoded from plasmids or chromosomes. In addition to being able to modulate RNA expression levels, cross-regulations between these systems can also influence their toxicity. This suggests the idea that they are involved in an interconnected regulatory network.
Collapse
|
22
|
Zhang SP, Wang Q, Quan SW, Yu XQ, Wang Y, Guo DD, Peng L, Feng HY, He YX. Type II toxin–antitoxin system in bacteria: activation, function, and mode of action. BIOPHYSICS REPORTS 2020. [DOI: 10.1007/s41048-020-00109-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
|
23
|
Ames JR, McGillick J, Murphy T, Reddem E, Bourne CR. Identifying a Molecular Mechanism That Imparts Species-Specific Toxicity to YoeB Toxins. Front Microbiol 2020; 11:959. [PMID: 32528435 PMCID: PMC7256200 DOI: 10.3389/fmicb.2020.00959] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 04/21/2020] [Indexed: 11/24/2022] Open
Abstract
The ribosome-dependent E. coli (Ec) mRNase toxin YoeB has been demonstrated to protect cells during thermal stress. Agrobacterium tumefaciens (At), a plant pathogen, also encodes a YoeB toxin. Initial studies indicated that AtYoeB does not impact the growth of Ec, but its expression is toxic to the native host At. The current work examines this species-specific effect. We establish the highly similar structure and function of Ec and AtYoeB toxins, including the ability of the AtYoeB toxin to inhibit Ec ribosomes in vitro. Comparison of YoeB sequences and structures highlights a four-residue helix between β-strands 2 and 3 that interacts with mRNA bases within the ribosome. This helix sequence is varied among YoeB toxins, and this variation correlates with bacterial classes of proteobacteria. When the four amino acid sequence of this helix is transplanted from EcYoeB onto AtYoeB, the resulting chimera gains toxicity to Ec cells and lessens toxicity to At cells. The reverse is also true, such that EcYoeB with the AtYoeB helix sequence is less toxic to Ec and gains toxicity to At cultures. We suggest this helix sequence directs mRNA sequence-specific degradation, which varies among proteobacterial classes, and thus controls growth inhibition and YoeB toxicity.
Collapse
Affiliation(s)
- Jessica R Ames
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, United States
| | - Julia McGillick
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, United States
| | - Tamiko Murphy
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, United States
| | - Eswar Reddem
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, United States
| | - Christina R Bourne
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, United States
| |
Collapse
|
24
|
Ziemski M, Leodolter J, Taylor G, Kerschenmeyer A, Weber-Ban E. Genome-wide interaction screen for Mycobacterium tuberculosis ClpCP protease reveals toxin-antitoxin systems as a major substrate class. FEBS J 2020; 288:111-126. [PMID: 32301575 DOI: 10.1111/febs.15335] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/12/2020] [Accepted: 04/14/2020] [Indexed: 12/30/2022]
Abstract
In Mycobacterium tuberculosis (Mtb), the Clp protease degradation pathway, mediated by the modular ClpCP and ClpXP protease complexes, is essential for growth and presents an attractive drug target. Employing a bacterial adenylate cyclase two-hybrid (BACTH) screening approach that we adapted to screen the proteome of an Mtb ORF library, we identify protein interaction partners of the ClpC1 chaperone on a genome-wide level. Our results demonstrate that bipartite type II toxin-antitoxin (TA) systems represent a major substrate class. Out of the 67 type II TA systems known in Mtb, 25 appear as ClpC1 interaction partners in the BACTH screen, including members of the VapBC, MazEF, and ParDE families, as well as a RelBE member that was identified biochemically. We show that antitoxins of the Vap and Rel families are degraded by ClpCP in vitro. We also demonstrate that ClpCP is responsible for mediating the N-end rule pathway, since the adaptor protein ClpS supports ClpC-dependent degradation of an N-end rule model substrate in vitro.
Collapse
Affiliation(s)
- Michal Ziemski
- Institute of Molecular Biology & Biophysics, ETH Zurich, Switzerland
| | - Julia Leodolter
- Institute of Molecular Biology & Biophysics, ETH Zurich, Switzerland
| | - Gabrielle Taylor
- Institute of Molecular Biology & Biophysics, ETH Zurich, Switzerland
| | | | - Eilika Weber-Ban
- Institute of Molecular Biology & Biophysics, ETH Zurich, Switzerland
| |
Collapse
|
25
|
Kuehl R, Morata L, Meylan S, Mensa J, Soriano A. When antibiotics fail: a clinical and microbiological perspective on antibiotic tolerance and persistence of Staphylococcus aureus. J Antimicrob Chemother 2020; 75:1071-1086. [PMID: 32016348 DOI: 10.1093/jac/dkz559] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Staphylococcus aureus is a major human pathogen causing a vast array of infections with significant mortality. Its versatile physiology enables it to adapt to various environments. Specific physiological changes are thought to underlie the frequent failure of antimicrobial therapy despite susceptibility in standard microbiological assays. Bacteria capable of surviving high antibiotic concentrations despite having a genetically susceptible background are described as 'antibiotic tolerant'. In this review, we put current knowledge on environmental triggers and molecular mechanisms of increased antibiotic survival of S. aureus into its clinical context. We discuss animal and clinical evidence of its significance and outline strategies to overcome infections with antibiotic-tolerant S. aureus.
Collapse
Affiliation(s)
- Richard Kuehl
- Service of Infectious Diseases, Hospital Clinic of Barcelona, University of Barcelona, IDIBAPS, Barcelona, Spain
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Basel, Switzerland
| | - Laura Morata
- Service of Infectious Diseases, Hospital Clinic of Barcelona, University of Barcelona, IDIBAPS, Barcelona, Spain
| | - Sylvain Meylan
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Basel, Switzerland
- Division de Maladies Infectieuses, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Josep Mensa
- Service of Infectious Diseases, Hospital Clinic of Barcelona, University of Barcelona, IDIBAPS, Barcelona, Spain
| | - Alex Soriano
- Service of Infectious Diseases, Hospital Clinic of Barcelona, University of Barcelona, IDIBAPS, Barcelona, Spain
| |
Collapse
|
26
|
Panasenko OO, Bezrukov F, Komarynets O, Renzoni A. YjbH Solubility Controls Spx in Staphylococcus aureus: Implication for MazEF Toxin-Antitoxin System Regulation. Front Microbiol 2020; 11:113. [PMID: 32117138 PMCID: PMC7016130 DOI: 10.3389/fmicb.2020.00113] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 01/17/2020] [Indexed: 12/23/2022] Open
Abstract
Bacterial cells respond to environmental stresses by modulating their gene expression and adjusting their proteome. In Staphylococcus aureus, selective degradation by ClpP protease eliminates damaged proteins and regulates the abundance of functional proteins such as many important stress-induced transcriptional regulators. Degradation by ClpP requires the unfolding activity of partner Clp ATPases, such as ClpX and ClpC, and assistance of substrate-specific adaptor proteins such as YjbH and TrfA. Herein, we demonstrated that YjbH is aggregated in response to growth stress stimuli, such as oxidative and antibiotic stresses. In consequence, its function as an adaptor protein is compromised. YjbH controls the degradation of the stress-induced transcriptional regulator, Spx. Aggregated YjbH cannot assist Spx degradation, which results in Spx accumulation. We discovered that depending on the stress stimulus, Spx can be soluble or insoluble, and, consequently, transcriptionally active or inactive. Therefore, Spx accumulation and solubility are key components governing activation of Spx-dependent genes. Spx positively regulates expression of a ClpCP adaptor protein TrfA. TrfA in turn is required for degradation of MazE antitoxin, the unstable component of the MazEF toxin-antitoxin system, that neutralizes the endoribonuclease activity of MazF toxin. Bacterial toxin-antitoxin systems are associated with dormancy and tolerance to antibiotics that are related to chronic and relapsing infections, and it is at present a key unresolved problem in medicine. MazF activity was linked to growth stasis, yet the precise environmental signals that trigger MazE degradation and MazF activation are poorly understood. Here we propose a model where YjbH serves as a sensor of environmental stresses for downstream regulation of MazEF activity. YjbH aggregation, soluble Spx, and TrfA, coordinately control MazE antitoxin levels and consequently MazF toxin activity. This model implies that certain stress conditions culminate in modulation of MazF activity resulting in growth stasis during in vivo infections.
Collapse
Affiliation(s)
- Olesya O Panasenko
- Service of Infectious Diseases, Department of Medical Specialties, University Hospital and Medical School of Geneva, Geneva, Switzerland.,Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Fedor Bezrukov
- Department of Physics and Astronomy, The University of Manchester, Manchester, United Kingdom
| | - Olga Komarynets
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Adriana Renzoni
- Service of Infectious Diseases, Department of Medical Specialties, University Hospital and Medical School of Geneva, Geneva, Switzerland.,Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| |
Collapse
|
27
|
Savijoki K, Miettinen I, Nyman TA, Kortesoja M, Hanski L, Varmanen P, Fallarero A. Growth Mode and Physiological State of Cells Prior to Biofilm Formation Affect Immune Evasion and Persistence of Staphylococcus aureus. Microorganisms 2020; 8:E106. [PMID: 31940921 PMCID: PMC7023439 DOI: 10.3390/microorganisms8010106] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 01/01/2023] Open
Abstract
The present study investigated Staphylococcus aureus ATCC25923 surfaceomes (cell surface proteins) during prolonged growth by subjecting planktonic and biofilm cultures (initiated from exponential or stationary cells) to label-free quantitative surfaceomics and phenotypic confirmations. The abundance of adhesion, autolytic, hemolytic, and lipolytic proteins decreased over time in both growth modes, while an opposite trend was detected for many tricarboxylic acid (TCA) cycle, reactive oxygen species (ROS) scavenging, Fe-S repair, and peptidolytic moonlighters. In planktonic cells, these changes were accompanied by decreasing and increasing adherence to hydrophobic surface and fibronectin, respectively. Specific RNA/DNA binding (cold-shock protein CspD and ribosomal proteins) and the immune evasion (SpA, ClfA, and IsaB) proteins were notably more abundant on fully mature biofilms initiated with stationary-phase cells (SDBF) compared to biofilms derived from exponential cells (EDBF) or equivalent planktonic cells. The fully matured SDBF cells demonstrated higher viability in THP-1 monocyte/macrophage cells compared to the EDBF cells. Peptidoglycan strengthening, specific urea-cycle, and detoxification enzymes were more abundant on planktonic than biofilm cells, indicating the activation of growth-mode specific pathways during prolonged cultivation. Thus, we show that S. aureus shapes its surfaceome in a growth mode-dependent manner to reach high levofloxacin tolerance (>200-times the minimum biofilm inhibitory concentration). This study also demonstrates that the phenotypic state of the cells prior to biofilm formation affects the immune-evasion and persistence-related traits of S. aureus.
Collapse
Affiliation(s)
- Kirsi Savijoki
- Pharmaceutical Design and Discovery (PharmDD) Group, Pharmaceutical Biology, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland; (I.M.); (M.K.); (L.H.); (A.F.)
| | - Ilkka Miettinen
- Pharmaceutical Design and Discovery (PharmDD) Group, Pharmaceutical Biology, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland; (I.M.); (M.K.); (L.H.); (A.F.)
| | - Tuula A. Nyman
- Department of Immunology, Institute of Clinical Medicine, University of Oslo and Rikshospitalet Oslo, 0372 Oslo, Norway; or
| | - Maarit Kortesoja
- Pharmaceutical Design and Discovery (PharmDD) Group, Pharmaceutical Biology, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland; (I.M.); (M.K.); (L.H.); (A.F.)
| | - Leena Hanski
- Pharmaceutical Design and Discovery (PharmDD) Group, Pharmaceutical Biology, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland; (I.M.); (M.K.); (L.H.); (A.F.)
| | - Pekka Varmanen
- Department of Food and Nutrition, University of Helsinki, 00014 Helsinki, Finland;
| | - Adyary Fallarero
- Pharmaceutical Design and Discovery (PharmDD) Group, Pharmaceutical Biology, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland; (I.M.); (M.K.); (L.H.); (A.F.)
| |
Collapse
|
28
|
Shivaee A, Mohammadzadeh R, Shahbazi S, Pardakhtchi E, Ohadi E, Kalani BS. Time-variable expression levels of mazF, atlE, sdrH, and bap genes during biofilm formation in Staphylococcus epidermidis. Acta Microbiol Immunol Hung 2019; 66:499-508. [PMID: 31198057 DOI: 10.1556/030.66.2019.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Staphylococcus epidermidis is an opportunistic pathogen causing infections related to the usage of implants and medical devices. Pathogenicity of this microorganism is mainly linked to its capability to form biofilm structures. Biofilm formation vastly depends on several factors including different proteins. We studied the expression levels of three proteins including SdrH, Bap, AtlE, and MazF at different time intervals during the course of biofilm formation. In this study, a catheter-derived S. epidermidis isolate with strong ability of biofilm formation was selected. PCR assay was used to detect sdrH, bap, atlE, and mazF genes in this isolate. Real-time PCR was used to determine the expression levels of these genes after 4, 8, and 20 h during the course of biofilm formation. The studied genes showed different expression levels at different time intervals during biofilm formation by real-time PCR method. Expression levels of atlE and sdrH genes were the highest at 4 h, whereas bap gene showed the highest expression level at 8 h during the course of biofilm formation. In addition, the expression level of mazF gene peaked at 4 h and then progressively decreased at 8 and 20 h. Our results suggest the importance of AtlE, SdrH, and MazF proteins in the establishment and development of the biofilm structure. In addition, our results showed the important role of protein Bap in the accumulation of biofilm structure. Future studies are required to understand the exact role of MazF in the process of biofilm formation.
Collapse
Affiliation(s)
- Ali Shivaee
- 1 Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Rokhsareh Mohammadzadeh
- 1 Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Shahla Shahbazi
- 2 Department of Bacteriology, Pasteur Institute of Iran, Teheran, Iran
| | - Elahe Pardakhtchi
- 3 Microbial Biotechnology Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Elnaz Ohadi
- 1 Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Behrooz Sadeghi Kalani
- 1 Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
- 3 Microbial Biotechnology Research Center, Iran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
29
|
ClpC affects the intracellular survival capacity of Staphylococcus aureus in non-professional phagocytic cells. Sci Rep 2019; 9:16267. [PMID: 31700127 PMCID: PMC6838064 DOI: 10.1038/s41598-019-52731-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 10/22/2019] [Indexed: 12/22/2022] Open
Abstract
Invasion and persistence of bacteria within host cells requires that they adapt to life in an intracellular environment. This adaptation induces bacterial stress through events such as phagocytosis and enhanced nutrient-restriction. During stress, bacteria synthesize a family of proteins known as heat shock proteins (HSPs) to facilitate adaptation and survival. Previously, we determined the Staphylococcus aureus HSP ClpC temporally alters bacterial metabolism and persistence. This led us to hypothesize that ClpC might alter intracellular survival. Inactivation of clpC in S. aureus strain DSM20231 significantly enhanced long-term intracellular survival in human epithelial (HaCaT) and endothelial (EA.hy926) cell lines, without markedly affecting adhesion or invasion. This phenotype was similar across a genetically diverse collection of S. aureus isolates, and was influenced by the toxin/antitoxin encoding locus mazEF. Importantly, MazEF alters mRNA synthesis and/or stability of S. aureus virulence determinants, indicating ClpC may act through the mRNA modulatory activity of MazEF. Transcriptional analyses of total RNAs isolated from intracellular DSM20231 and isogenic clpC mutant cells identified alterations in transcription of α-toxin (hla), protein A (spa), and RNAIII, consistent with the hypothesis that ClpC negatively affects the intracellular survival of S. aureus in non-professional phagocytic cells, via modulation of MazEF and Agr.
Collapse
|
30
|
Tian XL, Li M, Scinocca Z, Rutherford H, Li YH. ClpP is required for proteolytic regulation of type II toxin-antitoxin systems and persister cell formation in Streptococcus mutans. Access Microbiol 2019; 1:e000054. [PMID: 32974554 PMCID: PMC7470404 DOI: 10.1099/acmi.0.000054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 07/25/2019] [Indexed: 11/18/2022] Open
Abstract
The type II toxin-antitoxin (TA) modules, mazEF and relBE, in Streptococcus mutans have been implicated in stress response, antibiotic tolerance and persister cell formation. However, how S. mutans regulates these systems to prevent unwanted toxin activation and persister cell formation is unclear. In this study, we provide evidence that ClpP is required for the proteolytic regulation of these TA systems and persister cell formation in S. mutans following antibiotic challenge. A persister viability assay showed that S. mutans UA159 (WT) formed a larger quantity of persister cells than its isogenic mutant ΔclpP following antibiotic challenge. However, the lux reporter assay revealed that clpP deletion did not affect the transcriptional levels of mazEF and relBE, since no significant differences (P>0.05) in the reporter activities were detected between the wild-type and ΔclpP background. Instead, all antibiotics tested at a sub-minimum inhibitory concentration (sub-MIC) induced transcriptional levels of mazEF and relBE operons. We then examined the protein profiles of His-tagged MazE and RelB proteins in the UA159 and ΔclpP backgrounds by Western blotting analysis. The results showed that S. mutans strains grown under non-stress conditions expressed very low but detectable levels of MazE and RelB antitoxin proteins. Antibiotics at sub-MICs induced the levels of the MazE and RelB proteins, but the protein levels decreased rapidly in the wild-type background. In contrast, a stable level of MazE and RelB proteins could be detected in the ΔclpP mutant background, suggesting that both proteins accumulated in the ΔclpP mutant. We conclude that ClpP is required for the proteolytic regulation of cellular levels of the MazE and RelB antitoxins in S. mutans , which may play a critical role in modulating the TA activities and persister cell formation of this organism following antibiotic challenge.
Collapse
Affiliation(s)
- Xiao-Lin Tian
- Department of Applied Oral Sciences, Dalhousie Universit, Halifax, NS, Canada
| | - Miao Li
- Department of Applied Oral Sciences, Dalhousie Universit, Halifax, NS, Canada.,Lanzhou University, Gansu, PR China
| | - Zachariah Scinocca
- Department of Applied Oral Sciences, Dalhousie Universit, Halifax, NS, Canada
| | - Heather Rutherford
- Department of Applied Oral Sciences, Dalhousie Universit, Halifax, NS, Canada
| | - Yung-Hua Li
- Department of Applied Oral Sciences, Dalhousie Universit, Halifax, NS, Canada.,Department of Microbiology and Immunology, Dalhousie University, Halifax, NS, Canada
| |
Collapse
|
31
|
Riffaud C, Pinel-Marie ML, Pascreau G, Felden B. Functionality and cross-regulation of the four SprG/SprF type I toxin-antitoxin systems in Staphylococcus aureus. Nucleic Acids Res 2019; 47:1740-1758. [PMID: 30551143 PMCID: PMC6393307 DOI: 10.1093/nar/gky1256] [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: 08/02/2018] [Revised: 11/29/2018] [Accepted: 12/04/2018] [Indexed: 01/21/2023] Open
Abstract
Toxin–antitoxin (TA) systems are ubiquitous among bacteria, frequently expressed in multiple copies, and important for functions such as antibiotic resistance and persistence. Type I TA systems are composed of a stable toxic peptide whose expression is repressed by an unstable RNA antitoxin. Here, we investigated the functionalities, regulation, and possible cross-talk between three core genome copies of the pathogenicity island-encoded ‘sprG1/sprF1’ type I TA system in the human pathogen Staphylococcus aureus. Except for SprG4, all RNA from these pairs, sprG2/sprF2, sprG3/sprF3, sprG4/sprF4, are expressed in the HG003 strain. SprG2 and SprG3 RNAs encode toxic peptides whose overexpression triggers bacteriostasis, which is counteracted at the RNA level by the overexpression of SprF2 and SprF3 antitoxins. Complex formation between each toxin and its cognate antitoxin involves their overlapping 3′ ends, and each SprF antitoxin specifically neutralizes the toxicity of its cognate SprG toxin without cross-talk. However, overexpression studies suggest cross-regulations occur at the RNA level between the SprG/SprF TA systems during growth. When subjected to H2O2-induced oxidative stress, almost all antitoxin levels dropped, while only SprG1 and SprF1 were reduced during phagocytosis-induced oxidative stress. SprG1, SprF1, SprF2, SprG3 and SprF3 levels also decrease during hyperosmotic stress. This suggests that novel SprG/SprF TA systems are involved in S. aureus persistence.
Collapse
Affiliation(s)
- Camille Riffaud
- Université de Rennes 1, Inserm, BRM (Bacterial Regulatory RNAs and Medicine) UMR_S 1230, 35000 Rennes, France
| | - Marie-Laure Pinel-Marie
- Université de Rennes 1, Inserm, BRM (Bacterial Regulatory RNAs and Medicine) UMR_S 1230, 35000 Rennes, France
| | - Gaëtan Pascreau
- Université de Rennes 1, Inserm, BRM (Bacterial Regulatory RNAs and Medicine) UMR_S 1230, 35000 Rennes, France
| | - Brice Felden
- Université de Rennes 1, Inserm, BRM (Bacterial Regulatory RNAs and Medicine) UMR_S 1230, 35000 Rennes, France
| |
Collapse
|
32
|
Donegan NP, Manna AC, Tseng CW, Liu GY, Cheung AL. CspA regulation of Staphylococcus aureus carotenoid levels and σ B activity is controlled by YjbH and Spx. Mol Microbiol 2019; 112:532-551. [PMID: 31074903 DOI: 10.1111/mmi.14273] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/07/2019] [Indexed: 01/06/2023]
Abstract
Staphyloxanthin, a carotenoid in S. aureus, is a powerful antioxidant against oxidative stresses. The crtOPQMN operon driving pigment synthesis is under the control of σB . CspA, a cold shock protein, is known to control σB activity. To ascertain genes that regulate cspA, we screened a transposon library that exhibited reduced cspA expression and pigmentation. We found that the adaptor protein YjbH activates cspA expression. Spx, the redox-sensitive transcriptional regulator and a proteolytic target for YjbH and ClpXP, complexes with αCTD of RNAP prior to binding the cspA promoter to repress cspA activity. Increased cspA expression in trans in the inactive spx C10A mutant of JE2 did not enhance pigment production while it did in JE2, suggesting that cspA is downstream to Spx in pigmentation control. As the staphyloxanthin pigment is critical to S. aureus survival in human hosts, we demonstrated that the cspA and yjbH mutants survived less well than the parent in whole blood killing assay. Collectively, our studies suggest a pathway wherein YjbH and ClpXP proteolytically cleave Spx, a repressor of cspA transcription, to affect σB -dependent carotenoid expression, thus providing a critical link between intracellular redox sensing by Spx and carotenoid production to improve S. aureus survival during infections.
Collapse
Affiliation(s)
- Niles P Donegan
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Adhar C Manna
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Ching Wen Tseng
- Department of Pediatrics, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - George Y Liu
- Department of Pediatrics, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Ambrose L Cheung
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| |
Collapse
|
33
|
In Silico Insight into the Dominant Type II Toxin–Antitoxin Systems and Clp Proteases in Listeria monocytogenes and Designation of Derived Peptides as a Novel Approach to Interfere with this System. Int J Pept Res Ther 2019. [DOI: 10.1007/s10989-019-09868-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
34
|
McVicker G, Hollingshead S, Pilla G, Tang CM. Maintenance of the virulence plasmid in Shigella flexneri is influenced by Lon and two functional partitioning systems. Mol Microbiol 2019; 111:1355-1366. [PMID: 30767313 PMCID: PMC6519299 DOI: 10.1111/mmi.14225] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2019] [Indexed: 11/30/2022]
Abstract
Members of the genus Shigella carry a large plasmid, pINV, which is essential for virulence. In Shigella flexneri, pINV harbours three toxin‐antitoxin (TA) systems, CcdAB, GmvAT and VapBC that promote vertical transmission of the plasmid. Type II TA systems, such as those on pINV, consist of a toxic protein and protein antitoxin. Selective degradation of the antitoxin by proteases leads to the unopposed action of the toxin once genes encoding a TA system have been lost, such as following failure to inherit a plasmid harbouring a TA system. Here, we investigate the role of proteases in the function of the pINV TA systems and demonstrate that Lon, but not ClpP, is required for their activity during plasmid stability. This provides the first evidence that acetyltransferase family TA systems, such as GmvAT, can be regulated by Lon. Interestingly, S. flexneri pINV also harbours two putative partitioning systems, ParAB and StbAB. We show that both systems are functional for plasmid maintenance although their activity is masked by other systems on pINV. Using a model vector based on the pINV replicon, we observe temperature‐dependent differences between the two partitioning systems that contribute to our understanding of the maintenance of virulence in Shigella species.
Collapse
Affiliation(s)
- Gareth McVicker
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK
| | - Sarah Hollingshead
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK
| | - Giulia Pilla
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK
| | - Christoph M Tang
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK
| |
Collapse
|
35
|
Habib G, Zhu Q, Sun B. Bioinformatics and Functional Assessment of Toxin-Antitoxin Systems in Staphylococcus aureus. Toxins (Basel) 2018; 10:toxins10110473. [PMID: 30441856 PMCID: PMC6266405 DOI: 10.3390/toxins10110473] [Citation(s) in RCA: 15] [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: 10/14/2018] [Revised: 11/07/2018] [Accepted: 11/11/2018] [Indexed: 01/21/2023] Open
Abstract
Staphylococcus aureus is a nosocomial pathogen that can cause chronic to persistent infections. Among different mediators of pathogenesis, toxin-antitoxin (TA) systems are emerging as the most prominent. These systems are frequently studied in Escherichia coli and Mycobacterial species but rarely explored in S. aureus. In the present study, we thoroughly analyzed the S. aureus genome and screened all possible TA systems using the Rasta bacteria and toxin-antitoxin database. We further searched E. coli and Mycobacterial TA homologs and selected 67 TA loci as putative TA systems in S. aureus. The host inhibition of growth (HigBA) TA family was predominantly detected in S. aureus. In addition, we detected seven pathogenicity islands in the S. aureus genome that are enriched with virulence genes and contain 26 out of 67 TA systems. We ectopically expressed multiple TA genes in E. coli and S. aureus that exhibited bacteriostatic and bactericidal effects on cell growth. The type I Fst toxin created holes in the cell wall while the TxpA toxin reduced cell size and induced cell wall septation. Besides, we identified a new TA system whose antitoxin functions as a transcriptional autoregulator while the toxin functions as an inhibitor of autoregulation. Altogether, this study provides a plethora of new as well as previously known TA systems that will revitalize the research on S. aureus TA systems.
Collapse
Affiliation(s)
- Gul Habib
- Division of Molecular Medicine, Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China.
| | - Qing Zhu
- Division of Molecular Medicine, Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China.
| | - Baolin Sun
- Division of Molecular Medicine, Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China.
| |
Collapse
|
36
|
Relationship between the Viable but Nonculturable State and Antibiotic Persister Cells. J Bacteriol 2018; 200:JB.00249-18. [PMID: 30082460 DOI: 10.1128/jb.00249-18] [Citation(s) in RCA: 143] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Bacteria have evolved numerous means of survival in adverse environments with dormancy, as represented by "persistence" and the "viable but nonculturable" (VBNC) state, now recognized to be common modes for such survival. VBNC cells have been defined as cells which, induced by some stress, become nonculturable on media that would normally support their growth but which can be demonstrated by various methods to be alive and capable of returning to a metabolically active and culturable state. Persister cells have been described as a population of cells which, while not being antibiotic resistant, are antibiotic tolerant. This drug-tolerant phenotype is thought to be a result of stress-induced and stochastic physiological changes as opposed to mutational events leading to true resistance. In this review, we describe these two dormancy strategies, characterize the molecular underpinnings of each state, and highlight the similarities and differences between them. We believe these survival modes represent a continuum between actively growing and dead cells, with VBNC cells being in a deeper state of dormancy than persister cells.
Collapse
|
37
|
Mechanisms of Bacterial Tolerance and Persistence in the Gastrointestinal and Respiratory Environments. Clin Microbiol Rev 2018; 31:31/4/e00023-18. [PMID: 30068737 DOI: 10.1128/cmr.00023-18] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Pathogens that infect the gastrointestinal and respiratory tracts are subjected to intense pressure due to the environmental conditions of the surroundings. This pressure has led to the development of mechanisms of bacterial tolerance or persistence which enable microorganisms to survive in these locations. In this review, we analyze the general stress response (RpoS mediated), reactive oxygen species (ROS) tolerance, energy metabolism, drug efflux pumps, SOS response, quorum sensing (QS) bacterial communication, (p)ppGpp signaling, and toxin-antitoxin (TA) systems of pathogens, such as Escherichia coli, Salmonella spp., Vibrio spp., Helicobacter spp., Campylobacter jejuni, Enterococcus spp., Shigella spp., Yersinia spp., and Clostridium difficile, all of which inhabit the gastrointestinal tract. The following respiratory tract pathogens are also considered: Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Burkholderia cenocepacia, and Mycobacterium tuberculosis Knowledge of the molecular mechanisms regulating the bacterial tolerance and persistence phenotypes is essential in the fight against multiresistant pathogens, as it will enable the identification of new targets for developing innovative anti-infective treatments.
Collapse
|
38
|
Sierra R, Viollier P, Renzoni A. Linking toxin-antitoxin systems with phenotypes: A Staphylococcus aureus viewpoint. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2018; 1862:742-751. [PMID: 30056132 DOI: 10.1016/j.bbagrm.2018.07.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 07/04/2018] [Accepted: 07/17/2018] [Indexed: 10/28/2022]
Abstract
Toxin-antitoxin systems (TAS) are genetic modules controlling different aspects of bacterial physiology. They operate with versatility in an incredibly wide range of mechanisms. New TA modules with unexpected functions are continuously emerging from genome sequencing projects. Their discovery and functional studies have shed light on different characteristics of bacterial metabolism that are now applied to understanding clinically relevant questions and even proposed as antimicrobial treatment. Our main source of knowledge of TA systems derives from Gram-negative bacterial studies, but studies in Gram-positives are becoming more prevalent and provide new insights to TA functional mechanisms. In this review, we present an overview of the present knowledge of TA systems in the clinical pathogen Staphylococcus aureus, their implications in bacterial physiology and discuss relevant aspects that are driving TAS research. "This article is part of a Special Issue entitled: Dynamic gene expression, edited by Prof. Patrick Viollier".
Collapse
Affiliation(s)
- Roberto Sierra
- Geneva University Hospital, Service of Infectious Diseases, Geneva, Switzerland; Department of Microbiology and Molecular Medicine, University of Geneva, Switzerland
| | - Patrick Viollier
- Department of Microbiology and Molecular Medicine, University of Geneva, Switzerland
| | - Adriana Renzoni
- Geneva University Hospital, Service of Infectious Diseases, Geneva, Switzerland.
| |
Collapse
|
39
|
Zheng C, Zhao X, Zeng T, Cao M, Xu J, Shi G, Li J, Chen H, Bei W. Identification of four type II toxin-antitoxin systems in Actinobacillus pleuropneumoniae. FEMS Microbiol Lett 2018. [PMID: 28637172 DOI: 10.1093/femsle/fnx126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Toxin-antitoxin (TA) systems are small genetic elements that are widely prevalent in the genomes of bacteria and archaea. These modules have been identified in various bacteria and proposed to play an important role in bacterial physiology and virulence. However, their presence in the genomes of Actinobacillus species has received no attention. In this study, we describe the identification of four type II TA systems in Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia. Reverse transcription PCR analysis revealed that the genes encoding the toxin and antitoxin are co-transcribed. Overexpression of each toxin inhibited the growth of Escherichia coli, and the toxic effect could be counteracted by its cognate antitoxin. The pull-down experiments demonstrated that each toxin interacts with its cognate antitoxin in vivo. The promoter activity assays showed that each antitoxin could autoregulate either positively or negatively the TA operon transcription. In addition, the APJL_0660/0659 TA system is present in half of the detected serovars of A. pleuropneumoniae, while the others are present in all. Collectively, we identified four type II TA systems in A. pleuropneumoniae, and this study has laid the foundation for further functional study of these TA systems.
Collapse
Affiliation(s)
- Chengkun Zheng
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| | - Xigong Zhao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| | - Ting Zeng
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| | - Manman Cao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| | - Jiali Xu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| | - Guolin Shi
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| | - Jinquan Li
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Huanchun Chen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| | - Weicheng Bei
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| |
Collapse
|
40
|
Raymond-Bouchard I, Chourey K, Altshuler I, Iyer R, Hettich RL, Whyte LG. Mechanisms of subzero growth in the cryophile Planococcus halocryophilus determined through proteomic analysis. Environ Microbiol 2017; 19:4460-4479. [PMID: 28834033 DOI: 10.1111/1462-2920.13893] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 08/13/2017] [Indexed: 01/22/2023]
Abstract
The eurypsychrophilic bacterium Planococcus halocryophilus is capable of growth down to -15°C, making it ideal for studying adaptations to subzero growth. To increase our understanding of the mechanisms and pathways important for subzero growth, we performed proteomics on P. halocryophilus grown at 23°C, 23°C with 12% w/v NaCl and -10°C with 12% w/v NaCl. Many proteins with increased abundances at -10°C versus 23°C also increased at 23C-salt versus 23°C, indicating a closely tied relationship between salt and cold stress adaptation. Processes which displayed the largest changes in protein abundance were peptidoglycan and fatty acid (FA) synthesis, translation processes, methylglyoxal metabolism, DNA repair and recombination, and protein and nucleotide turnover. We identified intriguing targets for further research at -10°C, including PlsX and KASII (FA metabolism), DD-transpeptidase and MurB (peptidoglycan synthesis), glyoxalase family proteins (reactive electrophile response) and ribosome modifying enzymes (translation turnover). PemK/MazF may have a crucial role in translational reprogramming under cold conditions. At -10°C P. halocryophilus induces stress responses, uses resources efficiently, and carefully controls its growth and metabolism to maximize subzero survival. The present study identifies several mechanisms involved in subzero growth and enhances our understanding of cold adaptation.
Collapse
Affiliation(s)
- Isabelle Raymond-Bouchard
- Macdonald Campus, McGill University, 21,111 Lakeshore Rd, Ste.-Anne-de-Bellevue, QC, H9X 3V9, Canada
| | - Karuna Chourey
- Chemical Sciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN 37831, USA
| | - Ianina Altshuler
- Macdonald Campus, McGill University, 21,111 Lakeshore Rd, Ste.-Anne-de-Bellevue, QC, H9X 3V9, Canada
| | - Ramsunder Iyer
- Chemical Sciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN 37831, USA.,Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN 37996, USA
| | - Robert L Hettich
- Chemical Sciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN 37831, USA
| | - Lyle G Whyte
- Macdonald Campus, McGill University, 21,111 Lakeshore Rd, Ste.-Anne-de-Bellevue, QC, H9X 3V9, Canada
| |
Collapse
|
41
|
Gupta A, Venkataraman B, Vasudevan M, Gopinath Bankar K. Co-expression network analysis of toxin-antitoxin loci in Mycobacterium tuberculosis reveals key modulators of cellular stress. Sci Rep 2017; 7:5868. [PMID: 28724903 PMCID: PMC5517426 DOI: 10.1038/s41598-017-06003-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 06/07/2017] [Indexed: 11/09/2022] Open
Abstract
Research on toxin-antitoxin loci (TA loci) is gaining impetus due to their ubiquitous presence in bacterial genomes and their observed roles in stress survival, persistence and drug tolerance. The present study investigates the expression profile of all the seventy-nine TA loci found in Mycobacterium tuberculosis. The bacterium was subjected to multiple stress conditions to identify key players of cellular stress response and elucidate a TA-coexpression network. This study provides direct experimental evidence for transcriptional activation of each of the seventy-nine TA loci following mycobacterial exposure to growth-limiting environments clearly establishing TA loci as stress-responsive modules in M. tuberculosis. TA locus activation was found to be stress-specific with multiple loci activated in a duration-based response to a particular stress. Conditions resulting in arrest of cellular translation led to greater up-regulation of TA genes suggesting that TA loci have a primary role in arresting translation in the cell. Our study identifed higBA2 and vapBC46 as key loci that were activated in all the conditions tested. Besides, relBE1, higBA3, vapBC35, vapBC22 and higBA1 were also upregulated in multpile stresses. Certain TA modules exhibited co-activation across multiple conditions suggestive of a common regulatory mechanism.
Collapse
Affiliation(s)
- Amita Gupta
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India. .,Department of Biochemistry and Centre for Innovation in Infectious Diseases Research, Education and Training (CIIDRET), University of Delhi South Campus, New Delhi, 110021, India.
| | - Balaji Venkataraman
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Madavan Vasudevan
- Genome Informatics Research Group, Bionivid Technology Pvt Ltd, Bengaluru, 560043, India
| | - Kiran Gopinath Bankar
- Genome Informatics Research Group, Bionivid Technology Pvt Ltd, Bengaluru, 560043, India
| |
Collapse
|
42
|
Mukherjee A, Wheaton GH, Counts JA, Ijeomah B, Desai J, Kelly RM. VapC toxins drive cellular dormancy under uranium stress for the extreme thermoacidophile Metallosphaera prunae. Environ Microbiol 2017; 19:2831-2842. [PMID: 28585353 DOI: 10.1111/1462-2920.13808] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 05/29/2017] [Indexed: 11/28/2022]
Abstract
When abruptly exposed to toxic levels of hexavalent uranium, the extremely thermoacidophilic archaeon Metallosphaera prunae, originally isolated from an abandoned uranium mine, ceased to grow, and concomitantly exhibited heightened levels of cytosolic ribonuclease activity that corresponded to substantial degradation of cellular RNA. The M. prunae transcriptome during 'uranium-shock' implicated VapC toxins as possible causative agents of the observed RNA degradation. Identifiable VapC toxins and PIN-domain proteins encoded in the M. prunae genome were produced and characterized, three of which (VapC4, VapC7, VapC8) substantially degraded M. prunae rRNA in vitro. RNA cleavage specificity for these VapCs mapped to motifs within M. prunae rRNA. Furthermore, based on frequency of cleavage sequences, putative target mRNAs for these VapCs were identified; these were closely associated with translation, transcription, and replication. It is interesting to note that Metallosphaera sedula, a member of the same genus and which has a nearly identical genome sequence but not isolated from a uranium-rich biotope, showed no evidence of dormancy when exposed to this metal. M. prunae utilizes VapC toxins for post-transcriptional regulation under uranium stress to enter a cellular dormant state, thereby providing an adaptive response to what would otherwise be a deleterious environmental perturbation.
Collapse
Affiliation(s)
- Arpan Mukherjee
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Garrett H Wheaton
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
| | - James A Counts
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Brenda Ijeomah
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Jigar Desai
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Robert M Kelly
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
| |
Collapse
|
43
|
Pando JM, Pfeltz RF, Cuaron JA, Nagarajan V, Mishra MN, Torres NJ, Elasri MO, Wilkinson BJ, Gustafson JE. Ethanol-induced stress response of Staphylococcus aureus. Can J Microbiol 2017; 63:745-757. [PMID: 28521110 DOI: 10.1139/cjm-2017-0221] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Transcriptional profiles of 2 unrelated clinical methicillin-resistant Staphylococcus aureus (MRSA) isolates were analyzed following 10% (v/v) ethanol challenge (15 min), which arrested growth but did not reduce viability. Ethanol-induced stress (EIS) resulted in differential gene expression of 1091 genes, 600 common to both strains, of which 291 were upregulated. With the exception of the downregulation of genes involved with osmotic stress functions, EIS resulted in the upregulation of genes that contribute to stress response networks, notably those altered by oxidative stress, protein quality control in general, and heat shock in particular. In addition, genes involved with transcription, translation, and nucleotide biosynthesis were downregulated. relP, which encodes a small alarmone synthetase (RelP), was highly upregulated in both MRSA strains following ethanol challenge, and relP inactivation experiments indicated that this gene contributed to EIS growth arrest. A number of persistence-associated genes were also upregulated during EIS, including those that encode toxin-antitoxin systems. Overall, transcriptional profiling indicated that the MRSA investigated responded to EIS by entering a state of dormancy and by altering the expression of elements from cross protective stress response systems in an effort to protect preexisting proteins.
Collapse
Affiliation(s)
- Jasmine M Pando
- a Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA
| | - Richard F Pfeltz
- b BD Diagnostic Systems, Microbiology R&D Department, Sparks, MD 21152, USA
| | - Jesus A Cuaron
- a Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA
| | - Vijayaraj Nagarajan
- c Department of Biological Sciences, University of Southern Mississippi, Hattiesburg, MS 39406, USA
| | - Mukti N Mishra
- d Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Nathanial J Torres
- d Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Mohamed O Elasri
- c Department of Biological Sciences, University of Southern Mississippi, Hattiesburg, MS 39406, USA
| | - Brian J Wilkinson
- e Microbiology Group, School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - John E Gustafson
- a Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA.,d Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| |
Collapse
|
44
|
Gautam LK, Yadav M, Rathore JS. Functional annotation of a novel toxin-antitoxin system Xn-RelT of Xenorhabdus nematophila; a combined in silico and in vitro approach. J Mol Model 2017; 23:189. [PMID: 28508139 DOI: 10.1007/s00894-017-3361-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 04/26/2017] [Indexed: 12/19/2022]
Abstract
Toxin-antitoxin (TA) complexes play an important role in stress responses and programmed cell death in bacteria. The RelB-RelE toxin antitoxin system is well studied in Escherichia coli. In this study, we used combined in silico and in vitro approaches to study a novel Xn-RelT toxin from Xenorhabdus nematophila bearing its own antitoxin Xn-RelAT-a RelB homolog of E. coli. The structure for this toxin-antitoxin pair is yet unknown. We generated homology-based models of X. nematophila RelT toxin and antitoxin. The deduced models were further characterized for protein-nucleic acid, protein-protein interactions and gene ontology. A detrimental effect of recombinant Xn-RelT on host E. coli was determined through endogenous toxicity assay. When expressed from a isopropyl β-D-1-thiogalactopyranoside-regulated LacZ promoter, Xn-RelT toxin showed a toxic effect on E. coli cells. These observations imply that the conditional cooperativity governing the Xn-RelT TA operon in X. nematophila plays an important role in stress management and programmed cell death.
Collapse
Affiliation(s)
- Lalit Kumar Gautam
- School of Biotechnology, Gautam Buddha University, Yamuna Expressway, Gautam Buddha Nagar, Greater Noida, Uttar Pradesh, 201312, India.,Department of Biotechnology, Panjab University, Chandigarh, 160014, India
| | - Mohit Yadav
- School of Biotechnology, Gautam Buddha University, Yamuna Expressway, Gautam Buddha Nagar, Greater Noida, Uttar Pradesh, 201312, India
| | - Jitendra Singh Rathore
- School of Biotechnology, Gautam Buddha University, Yamuna Expressway, Gautam Buddha Nagar, Greater Noida, Uttar Pradesh, 201312, India.
| |
Collapse
|
45
|
Physical and Functional Interplay between MazF 1Bif and Its Noncognate Antitoxins from Bifidobacterium longum. Appl Environ Microbiol 2017; 83:AEM.03232-16. [PMID: 28213540 DOI: 10.1128/aem.03232-16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 02/09/2017] [Indexed: 11/20/2022] Open
Abstract
Bifidobacterium longum strain JDM301, a widely used commercial strain in China, encodes at least two MazEF-like modules and one RelBE-like toxin-antitoxin (TA) system in its chromosome, designated MazE1F1Bif, MazE2F2Bif, and RelBEBif, respectively. Bacterial TA systems play an important role in several stress responses, but the relationship between these TA systems is largely unknown. In this study, the interactions between MazF1Bif and MazE2Bif or RelBBif were assessed in B. longum strain JDM301. MazF1Bif caused the degradation of tufABif mRNA, and its toxicity was inhibited by forming a protein complex with its cognate antitoxin, MazE1Bif Notably, MazF1Bif toxicity was also partially neutralized when jointly expressed with noncognate antitoxin MazE2Bif or RelBBif Our results show that the two noncognate antitoxins also inhibited mRNA degradation caused by MazF1Bif toxin. Furthermore, the physical interplay between MazF1Bif and its noncognate antitoxins was confirmed by immunoprecipitation. These results suggest that MazF1Bif can arrest cell growth and that MazF1Bif toxicity can be neutralized by its cognate and noncognate antitoxins. These results imply that JDM301 uses a sophisticated toxin-antitoxin interaction network to alter its physiology when coping with environmental stress.IMPORTANCE Although toxin-antitoxin (TA) systems play an important role in several stress responses, the regulatory mechanisms of multiple TA system homologs in the bacterial genome remain largely unclear. In this study, the relationships between MazE1F1Bif and the other two TA systems of Bifidobacterium longum strain JDM301 were explored, and the interactions between MazF1Bif and MazE2Bif or RelBBif were characterized. In addition, the mRNA degradation activity of MazF1Bif was demonstrated. In particular, the interaction of the toxin with noncognate antitoxins was shown, even between different TA families (MazF1Bif toxin and RelBBif antitoxin) in JDM301. This work provides insight into the regulatory mechanisms of TA systems implicated in the stress responses of bifidobacteria.
Collapse
|
46
|
Burbank LP, Stenger DC. The DinJ/RelE Toxin-Antitoxin System Suppresses Bacterial Proliferation and Virulence of Xylella fastidiosa in Grapevine. PHYTOPATHOLOGY 2017; 107:388-394. [PMID: 27938243 DOI: 10.1094/phyto-10-16-0374-r] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Xylella fastidiosa, the causal agent of Pierce's disease of grapes, is a slow-growing, xylem-limited, bacterial pathogen. Disease progression is characterized by systemic spread of the bacterium through xylem vessel networks, causing leaf-scorching symptoms, senescence, and vine decline. It appears to be advantageous to this pathogen to avoid excessive blockage of xylem vessels, because living bacterial cells are generally found in plant tissue with low bacterial cell density and minimal scorching symptoms. The DinJ/RelE toxin-antitoxin system is characterized here for a role in controlling bacterial proliferation and population size during plant colonization. The DinJ/RelE locus is transcribed from two separate promoters, allowing for coexpression of antitoxin DinJ with endoribonuclease toxin RelE, in addition to independent expression of RelE. The ratio of antitoxin/toxin expressed is dependent on bacterial growth conditions, with lower amounts of antitoxin present under conditions designed to mimic grapevine xylem sap. A knockout mutant of DinJ/RelE exhibits a hypervirulent phenotype, with higher bacterial populations and increased symptom development and plant decline. It is likely that DinJ/RelE acts to prevent excessive population growth, contributing to the ability of the pathogen to spread systemically without completely blocking the xylem vessels and increasing probability of acquisition by the insect vector.
Collapse
Affiliation(s)
- Lindsey P Burbank
- United States Department of Agriculture-Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, Parlier, CA 93648-9757
| | - Drake C Stenger
- United States Department of Agriculture-Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, Parlier, CA 93648-9757
| |
Collapse
|
47
|
Ruangprasert A, Maehigashi T, Miles SJ, Dunham CM. Importance of the E. coli DinJ antitoxin carboxy terminus for toxin suppression and regulated proteolysis. Mol Microbiol 2017; 104:65-77. [PMID: 28164393 DOI: 10.1111/mmi.13641] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2017] [Indexed: 11/26/2022]
Abstract
Toxin-antitoxin genes play important roles in the regulation of bacterial growth during stress. One response to stress is selective proteolysis of antitoxin proteins which releases their cognate toxin partners causing rapid inhibition of growth. The features of toxin-antitoxin complexes that are important to inhibit toxin activity as well as to release the active toxin remain elusive. Furthermore, it is unclear how antitoxins are selected for proteolysis by cellular proteases. Here, we test the minimal structural requirements of the Escherichia coli DinJ antitoxin to suppress its toxin partner, YafQ. We find that DinJ-YafQ complex formation is critically dependent on the last ten C-terminal residues of DinJ. However, deletion of these 10 DinJ residues has little effect on transcriptional autorepression suggesting that the YafQ toxin is not a critical component of the repression complex in contrast to other toxin-antitoxin systems. We further demonstrate that loop 5 preceding these ten C-terminal residues is important for Lon-mediated proteolysis. These results provide important insights into the critical interactions between toxin-antitoxin pairs necessary to inhibit toxin activity and the regulated proteolysis of antitoxins.
Collapse
Affiliation(s)
- Ajchareeya Ruangprasert
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta, GA, 30322, USA
| | - Tatsuya Maehigashi
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta, GA, 30322, USA
| | - Stacey J Miles
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta, GA, 30322, USA
| | - Christine M Dunham
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta, GA, 30322, USA
| |
Collapse
|
48
|
Curtis TD, Takeuchi I, Gram L, Knudsen GM. The Influence of the Toxin/Antitoxin mazEF on Growth and Survival of Listeria monocytogenes under Stress. Toxins (Basel) 2017; 9:E31. [PMID: 28098783 PMCID: PMC5308263 DOI: 10.3390/toxins9010031] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/31/2016] [Accepted: 01/07/2017] [Indexed: 12/11/2022] Open
Abstract
A major factor in the resilience of Listeria monocytogenes is the alternative sigma factor B (σB). Type II Toxin/Antitoxin (TA) systems are also known to have a role in the bacterial stress response upon activation via the ClpP or Lon proteases. Directly upstream of the σB operon in L. monocytogenes is the TA system mazEF, which can cleave mRNA at UACMU sites. In this study, we showed that the mazEF TA locus does not affect the level of persister formation during treatment with antibiotics in lethal doses, but exerts different effects according to the sub-inhibitory stress added. Growth of a ΔmazEF mutant was enhanced relative to the wildtype in the presence of sub-inhibitory norfloxacin and at 42 °C, but was decreased when challenged with ampicillin and gentamicin. In contrast to studies in Staphylococcus aureus, we found that the mazEF locus did not affect transcription of genes within the σB operon, but MazEF effected the expression of the σB-dependent genes opuCA and lmo0880, with a 0.22 and 0.05 fold change, respectively, compared to the wildtype under sub-inhibitory norfloxacin conditions. How exactly this system operates remains an open question, however, our data indicates it is not analogous to the system of S. aureus, suggesting a novel mode of action for MazEF in L. monocytogenes.
Collapse
Affiliation(s)
- Thomas D Curtis
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Matematiktorvet Bldg. 301, DK-2800 Kongens Lyngby, Denmark.
| | - Ippei Takeuchi
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Matematiktorvet Bldg. 301, DK-2800 Kongens Lyngby, Denmark.
| | - Lone Gram
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Matematiktorvet Bldg. 301, DK-2800 Kongens Lyngby, Denmark.
| | - Gitte M Knudsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Matematiktorvet Bldg. 301, DK-2800 Kongens Lyngby, Denmark.
| |
Collapse
|
49
|
Lobato-Márquez D, Díaz-Orejas R, García-Del Portillo F. Toxin-antitoxins and bacterial virulence. FEMS Microbiol Rev 2016; 40:592-609. [PMID: 27476076 DOI: 10.1093/femsre/fuw022] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/08/2016] [Indexed: 12/25/2022] Open
Abstract
Bacterial virulence relies on a delicate balance of signals interchanged between the invading microbe and the host. This communication has been extensively perceived as a battle involving harmful molecules produced by the pathogen and host defenses. In this review, we focus on a largely unexplored element of this dialogue, as are toxin-antitoxin (TA) systems of the pathogen. TA systems are reported to respond to stresses that are also found in the host and, as a consequence, could modulate the physiology of the intruder microbe. This view is consistent with recent studies that demonstrate a contribution of distinct TA systems to virulence since their absence alters the course of the infection. TA loci are stress response modules that, therefore, could readjust pathogen metabolism to favor the generation of slow-growing or quiescent cells 'before' host defenses irreversibly block essential pathogen activities. Some toxins of these TA modules have been proposed as potential weapons used by the pathogen to act on host targets. We discuss all these aspects based on studies that support some TA modules as important regulators in the pathogen-host interface.
Collapse
Affiliation(s)
- Damián Lobato-Márquez
- Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, 28049 Madrid, Spain Centro de Investigaciones Biológicas-CSIC (CIB-CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Ramón Díaz-Orejas
- Centro de Investigaciones Biológicas-CSIC (CIB-CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Francisco García-Del Portillo
- Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, 28049 Madrid, Spain
| |
Collapse
|
50
|
Ni T, Ye F, Liu X, Zhang J, Liu H, Li J, Zhang Y, Sun Y, Wang M, Luo C, Jiang H, Lan L, Gan J, Zhang A, Zhou H, Yang CG. Characterization of Gain-of-Function Mutant Provides New Insights into ClpP Structure. ACS Chem Biol 2016; 11:1964-72. [PMID: 27171654 DOI: 10.1021/acschembio.6b00390] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
ATP-dependent Clp protease (ClpP), a highly conserved serine protease in vast bacteria, could be converted into a noncontrollable enzyme capable of degrading mature proteins in the presence of acyldepsipeptides (ADEPs). Here, we design such a gain-of-function mutant of Staphylococcus aureus ClpP (SaClpP) capable of triggering the same level of dysfunctional activity that occurs upon ADEPs treatment. The SaClpPY63A mutant degrades FtsZ in vivo and inhibits staphylococcal growth. The crystal structure of SaClpPY63A indicates that Asn42 would be an important domino to fall for further activation of ClpP. Indeed, the SaClpPN42AY63A mutant demonstrates promoted self-activated proteolysis, which is a result of an enlarged entrance pore as observed in cryo-electron microscopy images. In addition, the expression of the engineered clpP allele phenocopies treatment with ADEPs; inhibition of cell division occurs as does showing sterilizing with rifampicin antibiotics. Collectively, we show that the gain-of-function SaClpPN42AY63A mutant becomes a fairly nonspecific protease and kills persisters by degrading over 500 proteins, thus providing new insights into the structure of the ClpP protease.
Collapse
Affiliation(s)
- Tengfeng Ni
- Laboratory
of Chemical Biology, State Key Laboratory of Drug Research, Shanghai
Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fei Ye
- College
of Life Sciences, Zhejiang Sci-Tech University, Hangzhou 310018, China
- Drug
Design and Discovery Center, State Key Laboratory of Drug Research,
Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xing Liu
- CAS
Key Laboratory of Receptor Research, Shanghai Institute of Materia
Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jie Zhang
- Laboratory
of Chemical Biology, State Key Laboratory of Drug Research, Shanghai
Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Hongchuan Liu
- Laboratory
of Chemical Biology, State Key Laboratory of Drug Research, Shanghai
Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jiahui Li
- Laboratory
of Chemical Biology, State Key Laboratory of Drug Research, Shanghai
Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yingyi Zhang
- National
Center for Protein Science Shanghai, Institute of Biochemistry and
Cell Biology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai 201210, China
| | - Yinqiang Sun
- Experiment
Center for Science and Technology, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Meining Wang
- CAS
Key Laboratory of Receptor Research, Shanghai Institute of Materia
Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Cheng Luo
- Drug
Design and Discovery Center, State Key Laboratory of Drug Research,
Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Hualiang Jiang
- University of Chinese Academy of Sciences, Beijing 100049, China
- Drug
Design and Discovery Center, State Key Laboratory of Drug Research,
Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Lefu Lan
- Laboratory
of Chemical Biology, State Key Laboratory of Drug Research, Shanghai
Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianhua Gan
- School
of Life Sciences, Fudan University, Shanghai 200433, China
| | - Ao Zhang
- University of Chinese Academy of Sciences, Beijing 100049, China
- CAS
Key Laboratory of Receptor Research, Shanghai Institute of Materia
Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Hu Zhou
- University of Chinese Academy of Sciences, Beijing 100049, China
- CAS
Key Laboratory of Receptor Research, Shanghai Institute of Materia
Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Cai-Guang Yang
- Laboratory
of Chemical Biology, State Key Laboratory of Drug Research, Shanghai
Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|