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Wilkening RV, Langouët-Astrié C, Severn MM, Federle MJ, Horswill AR. Identifying genetic determinants of Streptococcus pyogenes-host interactions in a murine intact skin infection model. Cell Rep 2023; 42:113332. [PMID: 37889753 PMCID: PMC10841832 DOI: 10.1016/j.celrep.2023.113332] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/12/2023] [Accepted: 10/06/2023] [Indexed: 10/29/2023] Open
Abstract
Streptococcus pyogenes is an obligate human pathobiont associated with many disease states. Here, we present a model of S. pyogenes infection using intact murine epithelium. We were able to perform RNA sequencing to evaluate genetic changes undertaken by both the bacterium and host at 5 and 24 h post-infection. Analysis of these genomic data demonstrate that S. pyogenes undergoes genetic adaptation to successfully infect the murine epithelium, including changes to metabolism and activation of the Rgg2/Rgg3 quorum-sensing (QS) system. Subsequent experiments demonstrate that an intact Rgg2/Rgg3 QS cascade is necessary to establish a stable superficial skin infection. QS cascade activation results in increased murine morbidity and bacterial burden on the skin. This phenotype is associated with gross changes to the murine skin and with evidence of inflammation. These experiments offer a method to investigate S. pyogenes-epithelial interactions and demonstrate that a well-studied QS pathway is critical to a persistent infection.
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Affiliation(s)
- Reid V Wilkening
- Section of Pediatric Critical Care Medicine, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO 80045, USA; Department of Microbiology and Immunology, University of Colorado School of Medicine, Aurora, CO 80045, USA.
| | - Christophe Langouët-Astrié
- Section of Pulmonary Sciences and Critical Care, Department of Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Morgan M Severn
- Department of Microbiology and Immunology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Michael J Federle
- Department of Pharmaceutical Sciences, University of Illinois Chicago, Chicago, IL 60607, USA
| | - Alexander R Horswill
- Department of Microbiology and Immunology, University of Colorado School of Medicine, Aurora, CO 80045, USA; Department of Veterans Affairs, Eastern Colorado Healthcare System, Aurora, CO 80045, USA.
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2
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Plainvert C, Rosinski-Chupin I, Weckel A, Lambert C, Touak G, Sauvage E, Poyart C, Glaser P, Fouet A. A Novel CovS Variant Harbored by a Colonization Strain Reduces Streptococcus pyogenes Virulence. J Bacteriol 2023; 205:e0003923. [PMID: 36920220 PMCID: PMC10127592 DOI: 10.1128/jb.00039-23] [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: 02/02/2023] [Accepted: 02/16/2023] [Indexed: 03/16/2023] Open
Abstract
Streptococcus pyogenes, also known as group A Streptococcus, causes a wide variety of diseases ranging from mild noninvasive to severe invasive infections. To identify possible causes of colonization-to-invasive switches, we determined the genomic sequences of 10 isolates from five pairs each composed of an invasive strain and a carriage strain originating from five infectious clusters. Among them, one pair displayed a single-nucleotide difference in covS, encoding the sensor histidine kinase of the two-component CovRS system that controls the expression of 15% of the genome. In contrast to previously described cases where the invasive strains harbor nonfunctional CovS proteins, the carriage strain possessed the mutation covST115C, leading to the replacement of the tyrosine at position 39 by a histidine. The CovSY39H mutation affected the expression of the genes from the CovR regulon in a unique fashion. Genes usually overexpressed in covS mutant strains were underexpressed and vice versa. Furthermore, the covS mutant strain barely responded to the addition of the CovS-signaling compounds Mg2+ and LL-37. The variations in the accumulation of two virulence factors paralleled the transcription modifications. In addition, the covST115C mutant strain showed less survival than its wild-type counterpart in murine macrophages. Finally, in two murine models of infection, the covS mutant strain was less virulent than the wild-type strain. Our study suggests that the CovSY39H protein compromises CovS phosphatase activity and that this yields a noninvasive strain. IMPORTANCE Streptococcus pyogenes, also known as group A Streptococcus, causes a wide variety of diseases, leading to 517,000 deaths yearly. The two-component CovRS system, which responds to MgCl2 and the antimicrobial peptide LL-37, controls the expression of 15% of the genome. Invasive strains may harbor nonfunctional CovS sensor proteins that lead to the derepression of most virulence genes. We isolated a colonization strain that harbors a novel covS mutation. This mutant strain harbored a transcriptome profile opposite that of other covS mutant strains, barely responded to environmental signals, and was less virulent than the wild-type strain. This supports the importance of the derepression of the expression of most virulence genes, via mutations that impact the phosphorylation of the regulator CovR, for favoring S. pyogenes invasive infections.
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Affiliation(s)
- Céline Plainvert
- Université Paris Cité, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France
- Service de Bactériologie, CNR des Streptocoques, Hôpitaux Universitaires Paris Centre, Paris, France
| | - Isabelle Rosinski-Chupin
- Institut Pasteur, Ecologie et Evolution de la Résistance aux Antibiotiques, UMR3525, Paris, France
| | - Antonin Weckel
- Université Paris Cité, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France
| | - Clara Lambert
- Université Paris Cité, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France
| | - Gérald Touak
- Service de Bactériologie, CNR des Streptocoques, Hôpitaux Universitaires Paris Centre, Paris, France
| | - Elisabeth Sauvage
- Institut Pasteur, Ecologie et Evolution de la Résistance aux Antibiotiques, UMR3525, Paris, France
| | - Claire Poyart
- Université Paris Cité, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France
- Service de Bactériologie, CNR des Streptocoques, Hôpitaux Universitaires Paris Centre, Paris, France
| | - Philippe Glaser
- Institut Pasteur, Ecologie et Evolution de la Résistance aux Antibiotiques, UMR3525, Paris, France
| | - Agnès Fouet
- Université Paris Cité, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France
- Service de Bactériologie, CNR des Streptocoques, Hôpitaux Universitaires Paris Centre, Paris, France
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3
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Kant S, Sun Y, Pancholi V. StkP- and PhpP-Mediated Posttranslational Modifications Modulate the S. pneumoniae Metabolism, Polysaccharide Capsule, and Virulence. Infect Immun 2023; 91:e0029622. [PMID: 36877045 PMCID: PMC10112228 DOI: 10.1128/iai.00296-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 02/09/2023] [Indexed: 03/07/2023] Open
Abstract
Pneumococcal Ser/Thr kinase (StkP) and its cognate phosphatase (PhpP) play a crucial role in bacterial cytokinesis. However, their individual and reciprocal metabolic and virulence regulation-related functions have yet to be adequately investigated in encapsulated pneumococci. Here, we demonstrate that the encapsulated pneumococcal strain D39-derived D39ΔPhpP and D39ΔStkP mutants displayed differential cell division defects and growth patterns when grown in chemically defined media supplemented with glucose or nonglucose sugars as the sole carbon source. Microscopic and biochemical analyses supported by RNA-seq-based global transcriptomic analyses of these mutants revealed significantly down- and upregulated polysaccharide capsule formation and cps2 genes in D39ΔPhpP and D39ΔStkP mutants, respectively. While StkP and PhpP individually regulated several unique genes, they also participated in sharing the regulation of the same set of differentially regulated genes. Cps2 genes were reciprocally regulated in part by the StkP/PhpP-mediated reversible phosphorylation but independent of the MapZ-regulated cell division process. StkP-mediated dose-dependent phosphorylation of CcpA proportionately inhibited CcpA-binding to Pcps2A, supporting increased cps2 gene expression and capsule formation in D39ΔStkP. While the attenuation of the D39ΔPhpP mutant in two mouse infection models corroborated with several downregulated capsules-, virulence-, and phosphotransferase systems (PTS)-related genes, the D39ΔStkP mutant with increased amounts of polysaccharide capsules displayed significantly decreased virulence in mice compared to the D39 wild-type, but more virulence compared to D39ΔPhpP. NanoString technology-based inflammation-related gene expression and Meso Scale Discovery-based multiplex chemokine analysis of human lung cells cocultured with these mutants confirmed their distinct virulence phenotypes. StkP and PhpP may, therefore, serve as critical therapeutic targets.
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Affiliation(s)
- Sashi Kant
- Department of Pathology, Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Youcheng Sun
- Department of Pathology, Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Vijay Pancholi
- Department of Pathology, Ohio State University College of Medicine, Columbus, Ohio, USA
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Chaudhary R, Kota S, Misra HS. DivIVA Phosphorylation Affects Its Dynamics and Cell Cycle in Radioresistant Deinococcus radiodurans. Microbiol Spectr 2023; 11:e0314122. [PMID: 36744915 PMCID: PMC10100863 DOI: 10.1128/spectrum.03141-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 01/06/2023] [Indexed: 02/07/2023] Open
Abstract
DivIVA is a member of the Min family of proteins that spatially regulates septum formation at the midcell position and cell pole determination in Bacillus subtilis. Deinococcus radiodurans, a Gram-positive coccus-shaped bacterium, is characterized by its extreme resistance to DNA-damaging agents, including radiation. D. radiodurans cells exposed to gamma radiation undergo cell division arrest by as-yet-uncharacterized mechanisms. divIVA is shown to be an essential cell division gene in this bacterium, and DivIVA of D. radiodurans (drDivIVA) interacts with genome segregation proteins through its N-terminal region. Earlier, RqkA, a gamma radiation-responsive Ser/Thr quinoprotein kinase, was characterized for its role in radioresistance in D. radiodurans. Here, we showed that RqkA phosphorylates drDivIVA at the threonine 19 (T19) residue. The phospho-mimetic mutant with a mutation of T19 to E19 in DivIVA (DivIVAT19E) is found to be functionally different from the phospho-ablative mutant (DivIVAT19A) or the wild-type drDivIVA. A DivIVAT19E-red fluorescent protein (RFP) fusion expressed in the wild-type background showed the arrest in the typical dynamics of drDivIVA and the loss of its interaction with the genome segregation protein ParA2. The allelic replacement of divIVA with divIVAT19E-rfp was not tolerated unless drDivIVA was expressed episomally, while there was no phenotypic change when the wild-type allele was replaced with either divIVAT19A-rfp or divIVA-rfp. These results suggested that the phosphorylation of T19 in drDivIVA by RqkA affected its in vivo functions, which may contribute to the cell cycle arrest in this bacterium. IMPORTANCE Deinococcus radiodurans, a radioresistant bacterium, lacks LexA/RecA-mediated DNA damage response and cell cycle regulation as known in other bacteria. However, it adjusts its transcriptome and proteome upon DNA damage. In eukaryotes, the DNA damage response and cell cycle are regulated by Ser/Thr protein kinases. In D. radiodurans, we characterized a gamma radiation-responsive Ser/Thr quinoprotein kinase (RqkA) that phosphorylated DNA repair and cell division proteins in this bacterium. In previous work, the effect of S/T phosphorylation by RqkA on activity improvement of the DNA repair proteins has been demonstrated. This study reports that Ser phosphorylation by RqkA attenuates the function of a cell polarity and plane of cell division-determining protein, DivIVA, and its cellular dynamics in response to DNA damage, which might help to understand the mechanism of cell cycle regulation in this bacterium.
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Affiliation(s)
- Reema Chaudhary
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India
- Life Sciences, Homi Bhabha National Institute, Mumbai, India
| | - Swathi Kota
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India
- Life Sciences, Homi Bhabha National Institute, Mumbai, India
| | - Hari S. Misra
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India
- Life Sciences, Homi Bhabha National Institute, Mumbai, India
- School of Science, GITAM, Visakhapatnam, Andhra Pradesh, India
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5
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Pancholi V. Editorial: Post-translational Modification in Response to Stresses in Bacteria. Front Microbiol 2022; 13:844854. [PMID: 35273590 PMCID: PMC8901876 DOI: 10.3389/fmicb.2022.844854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 01/28/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Vijay Pancholi
- Department of Pathology, The Ohio State University, Columbus, OH, United States
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6
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Roseobacter group probiotics exhibit differential killing of fish pathogenic Tenacibaculum species. Appl Environ Microbiol 2022; 88:e0241821. [PMID: 35080904 DOI: 10.1128/aem.02418-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fish pathogenic bacteria of the Tenacibaculum genus are a serious emerging concern in modern aquaculture, causing tenacibaculosis in a broad selection of cultured finfish. Data describing their virulence mechanisms are scarce and few means, antibiotic treatment aside, are available to control their proliferation in aquaculture systems. We genome sequenced a collection of 19 putative Tenacibaculum isolates from outbreaks at two aquaculture facilities and tested their susceptibility to treatment with tropodithietic acid (TDA)-producing Roseobacter group probiotics. We found that local outbreaks of Tenacibaculum can involve heterogeneous assemblages of species and strains with the capacity to produce multiple different virulence factors related to host invasion and infection. The probiotic Phaeobacter piscinae S26 proved efficient in killing pathogenic Tenacibaculum species such as T. maritimum, T. soleae, and some T. discolor strains. However, the T. mesophilum and T. gallaicum species exhibit natural tolerance towards TDA and are hence not likely to be easily killed by TDA-producing probiotics. Tolerance towards TDA in Tenacibaculum is likely involving multiple inherent physiological features pertaining to electron and proton transport, iron sequestration, and potentially also drug efflux mechanisms, as genetic determinants encoding such features were significantly associated with TDA tolerance. Collectively, our results support the use of TDA-producers to prevent tenacibaculosis, however, their efficacy is likely limited to some Tenacibaculum species. Importance A productive and sustainable aquaculture sector is needed to meet the UN sustainable development goals (SDGs) and supply the growing world population with high-protein food sources. A sustainable way to prevent disease outbreaks in the industry is the application of probiotic bacteria that can antagonize fish pathogens in the aquaculture systems. TDA-producing Roseobacter group probiotics have proven efficient in killing important vibrio pathogens and protecting fish larvae against infection, yet their efficacy against different fish pathogenic species of the Tenacibaculum genus has not been explored. Therefore, we tested the efficacy of such potential probiotics against a collection of different Tenacibaculum isolates and found the probiotic to efficiently kill a subset of relevant strains and species, supporting their use as sustainable disease control measure in aquaculture.
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7
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Kant S, Pancholi V. Novel Tyrosine Kinase-Mediated Phosphorylation With Dual Specificity Plays a Key Role in the Modulation of Streptococcus pyogenes Physiology and Virulence. Front Microbiol 2021; 12:689246. [PMID: 34950110 PMCID: PMC8689070 DOI: 10.3389/fmicb.2021.689246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 10/25/2021] [Indexed: 11/15/2022] Open
Abstract
Streptococcus pyogenes (Group A Streptococcus, GAS) genomes do not contain a gene encoding a typical bacterial-type tyrosine kinase (BY-kinase) but contain an orphan gene-encoding protein Tyr-phosphatase (SP-PTP). Hence, the importance of Tyr-phosphorylation is underappreciated and not recognized for its role in GAS pathophysiology and pathogenesis. The fact that SP-PTP dephosphorylates Abl-tyrosine kinase-phosphorylated myelin basic protein (MBP), and SP-STK (S. pyogenes Ser/Thr kinase) also autophosphorylates its Tyr101-residue prompted us to identify a putative tyrosine kinase and Tyr-phosphorylation in GAS. Upon a genome-wide search of kinases possessing a classical Walker motif, we identified a non-canonical tyrosine kinase M5005_Spy_1476, a ∼17 kDa protein (153 aa) (SP-TyK). The purified recombinant SP-TyK autophosphorylated in the presence of ATP. In vitro and in vivo phosphoproteomic analyses revealed two key phosphorylated tyrosine residues located within the catalytic domain of SP-TyK. An isogenic mutant lacking SP-TyK derived from the M1T1 strain showed a retarded growth pattern. It displayed defective cell division and long chains with multiple parallel septa, often resulting in aggregates. Transcriptomic analysis of the mutant revealed 287 differentially expressed genes responsible for GAS pathophysiology and pathogenesis. SP-TyK also phosphorylated GAS CovR, WalR, SP-STP, and SDH/GAPDH proteins with dual specificity targeting their Tyr/Ser/Thr residues as revealed by biochemical and mass-spectrometric-based phosphoproteomic analyses. SP-TyK-phosphorylated CovR bound to PcovR efficiently. The mutant displayed sustained release of IL-6 compared to TNF-α during co-culturing with A549 lung cell lines, attenuation in mice sepsis model, and significantly reduced ability to adhere to and invade A549 lung cells and form biofilms on abiotic surfaces. SP-TyK, thus, plays a critical role in fine-tuning the regulation of key cellular functions essential for GAS pathophysiology and pathogenesis through post-translational modifications and hence, may serve as a promising target for future therapeutic developments.
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8
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Hu Q, Yao L, Liao X, Zhang LS, Li HT, Li TT, Jiang QG, Tan MF, Li L, Draheim RR, Huang Q, Zhou R. Comparative Phenotypic, Proteomic, and Phosphoproteomic Analysis Reveals Different Roles of Serine/Threonine Phosphatase and Kinase in the Growth, Cell Division, and Pathogenicity of Streptococcus suis. Microorganisms 2021; 9:microorganisms9122442. [PMID: 34946045 PMCID: PMC8707513 DOI: 10.3390/microorganisms9122442] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/22/2021] [Accepted: 11/22/2021] [Indexed: 11/24/2022] Open
Abstract
Eukaryote-like serine/threonine kinases (STKs) and cognate phosphatases (STPs) comprise an important regulatory system in many bacterial pathogens. The complexity of this regulatory system has not been fully understood due to the presence of multiple STKs/STPs in many bacteria and their multiple substrates involved in many different physiological and pathogenetic processes. Streptococci are the best materials for the study due to a single copy of the gene encoding STK and its cognate STP. Although several studies have been done to investigate the roles of STK and STP in zoonotic Streptococcus suis, respectively, few studies were performed on the coordinated regulatory roles of this system. In this study, we carried out a systemic study on STK/STP in S. suis by using a comparative phenotypic, proteomic, and phosphoproteomic analysis. Mouse infection assays revealed that STK played a much more important role in S. suis pathogenesis than STP. The ∆stk and ∆stp∆stk strains, but not ∆stp, showed severe growth retardation. Moreover, both ∆stp and ∆stk strains displayed defects in cell division, but they were abnormal in different ways. The comparative proteomics and phosphoproteomics revealed that deletion of stk or stp had a significant influence on protein expression. Interestingly, more virulence factors were found to be downregulated in ∆stk than ∆stp. In ∆stk strain, a substantial number of the proteins with a reduced phosphorylation level were involved in cell division, energy metabolism, and protein translation. However, only a few proteins showed increased phosphorylation in ∆stp, which also included some proteins related to cell division. Collectively, our results show that both STP and STK are critical regulatory proteins for S. suis and that STK seems to play more important roles in growth, cell division, and pathogenesis.
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Affiliation(s)
- Qiao Hu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Lun Yao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Xia Liao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Liang-Sheng Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Hao-Tian Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Ting-Ting Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Qing-Gen Jiang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Mei-Fang Tan
- Institute of Animal Husbandry and Veterinary Science, Jiangxi Academy of Agricultural Sciences, Nanchang 330200, China;
| | - Lu Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
- Cooperative Innovation Center of Sustainable Pig Production, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology of China, Wuhan 430070, China
| | - Roger R. Draheim
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2UP, UK;
| | - Qi Huang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
- Cooperative Innovation Center of Sustainable Pig Production, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology of China, Wuhan 430070, China
- Correspondence: (Q.H.); (R.Z.)
| | - Rui Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
- Cooperative Innovation Center of Sustainable Pig Production, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology of China, Wuhan 430070, China
- Correspondence: (Q.H.); (R.Z.)
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9
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Dai W, Chen G, Bi X, Zhong H, Wang X, Dong S, Lv D, Zhang S, Zhang D, Wang N. Light limitation inducing overcompensatory growth of cyanobacteria and function of serine/threonine kinase (STK) genes involved. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2021; 83:1347-1356. [PMID: 33767041 DOI: 10.2166/wst.2021.071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The rapid overcompensatory growth that appears when cyanobacteria are supplied with adequate resources after a period of resource deprivation might contribute to the occurrence of cyanobacterial blooms. We investigated the changing characteristics of overcompensatory growth and serine/threonine kinase (STK) genes expression of cyanobacterium Microcystis aeruginosa in response to light limitation. The results showed M. aeruginosa exhibited overcompensatory growth for 2 days after light recovery, during which the increase in growth was inversely related to light intensity. Expression of STK genes, such as spkD, was upregulated significantly at 0.5-4 h after light recovery (P < 0.05). To investigate the function of STK genes in the overcompensatory growth, M. aeruginosa spkD was heterologously expressed in Synechocystis. Transgenic Synechocystis exhibited greater and longer overcompensatory growth than wild-type Synechocystis after light recovery. Relative expression levels of STK genes in transgenic Synechocystis were significantly higher than those in wild-type Synechocystis at 24 h of light recovery (P < 0.05). Heterologous expression of Microcystis spkD might stimulate overcompensatory growth of Synechocystis by affecting its STK gene expression.
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Affiliation(s)
- Wei Dai
- Key Laboratory of Aquatic-Ecology and Aquaculture of Tianjin, College of Fishery, Tianjin Agricultural University, Tianjin, China E-mail: ; † Wei Dai and Gao Chen are co-first authors of the article
| | - Gao Chen
- Biotechnology Research Center, Shandong Academy of Agricultural Sciences, Ji'nan, China and Shandong Provincial Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Ji'nan, China; † Wei Dai and Gao Chen are co-first authors of the article
| | - Xiangdong Bi
- Key Laboratory of Aquatic-Ecology and Aquaculture of Tianjin, College of Fishery, Tianjin Agricultural University, Tianjin, China E-mail:
| | - Huairong Zhong
- Biotechnology Research Center, Shandong Academy of Agricultural Sciences, Ji'nan, China and Shandong Provincial Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Ji'nan, China
| | - Xueying Wang
- Key Laboratory of Aquatic-Ecology and Aquaculture of Tianjin, College of Fishery, Tianjin Agricultural University, Tianjin, China E-mail:
| | - Shaojie Dong
- Key Laboratory of Aquatic-Ecology and Aquaculture of Tianjin, College of Fishery, Tianjin Agricultural University, Tianjin, China E-mail:
| | - Dong Lv
- Key Laboratory of Aquatic-Ecology and Aquaculture of Tianjin, College of Fishery, Tianjin Agricultural University, Tianjin, China E-mail:
| | - Shulin Zhang
- Key Laboratory of Aquatic-Ecology and Aquaculture of Tianjin, College of Fishery, Tianjin Agricultural University, Tianjin, China E-mail:
| | - Dajuan Zhang
- Key Laboratory of Aquatic-Ecology and Aquaculture of Tianjin, College of Fishery, Tianjin Agricultural University, Tianjin, China E-mail:
| | - Na Wang
- Key Laboratory of Aquatic-Ecology and Aquaculture of Tianjin, College of Fishery, Tianjin Agricultural University, Tianjin, China E-mail:
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10
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Liu H, Ye C, Fu H, Yue M, Li X, Fang W. Stk and Stp1 participate in Streptococcus suis serotype 2 pathogenesis by regulating capsule thickness and translocation of certain virulence factors. Microb Pathog 2020; 152:104607. [PMID: 33161059 DOI: 10.1016/j.micpath.2020.104607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/30/2020] [Accepted: 11/02/2020] [Indexed: 11/17/2022]
Abstract
Eukaryotic-like serine/threonine protein kinase (eSTK) and phosphatase (eSTP) play multiple roles in pathogenesis of many Gram-positive bacteria. eSTK (Stk) and eSTP (Stp1) of Streptococcus suis serotype 2 (S. suis 2) have also been reported to be virulence-associated, but their roles and underlying mechanisms in S. suis 2 pathogenesis require further investigation. We constructed mutants of stk or stp1 deletion using the virulent S. suis 2 isolate 05ZYH33 as the parental strain. Both Δstk and Δstp1 mutants showed abnormal cell division shown as increased chain length. This might be due to regulation by Stk and Stp1 of the phosphorylation status of the bacterial division protein DivIVA. Both mutants showed increased adhesion but reduced invasion to epithelial and endothelial cells. The two mutants were more readily phagocytosed by murine RAW264.7 macrophages. Western blotting revealed that GAPDH (glyceraldehyde-3-phosphate dehydrogenase), an important adhesin of S. suis, was significantly increased in the surface-associated and secreted fractions of the two mutant strains. Because increased adhesion of the mutant strains Δstk and Δstp1 to endothelial cells could be significantly inhibited by anti-GAPDH serum, we suppose that aberrant translocation of GAPDH due to deletion of the stk or stp1 gene contributed to increased interaction with host cells. The Δstk mutant showed reduced survival in macrophages, while the Δstp1 mutant showed increased survival probably as a result of increased capsule thickness. Enhanced hemolytic activity of the Δstk mutant could be due to increased secretion of suilysin. Both mutants exhibited reduced survival in pig whole blood and attenuated virulence to mice. Taken together, these results suggest that Stk and Stp1 can modulate S. suis cell division by post-translational modification of DivIVA, and regulate translocation of certain virulence factors, thereby benefiting its pathogenicity by compromising its interactions with the host.
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Affiliation(s)
- Hanze Liu
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang, 310058, China.
| | - Chaofeng Ye
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang, 310058, China.
| | - Hao Fu
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang, 310058, China.
| | - Min Yue
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang, 310058, China.
| | - Xiaoliang Li
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang, 310058, China.
| | - Weihuan Fang
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang, 310058, China.
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11
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Djorić D, Minton NE, Kristich CJ. The enterococcal PASTA kinase: A sentinel for cell envelope stress. Mol Oral Microbiol 2020; 36:132-144. [PMID: 32945615 DOI: 10.1111/omi.12313] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/05/2020] [Accepted: 09/08/2020] [Indexed: 12/12/2022]
Abstract
Enterococci are Gram-positive, opportunistic pathogens that reside throughout the gastrointestinal tracts of most terrestrial organisms. Enterococci are resistant to many antibiotics, which makes enterococcal infections difficult to treat. Enterococci are also particularly hardy bacteria that can tolerate a variety of environmental stressors. Understanding how enterococci sense and respond to the extracellular environment to enact adaptive biological responses may identify new targets that can be exploited for development of treatments for enterococcal infections. Bacterial eukaryotic-like serine/threonine kinases (eSTKs) and cognate phosphatases (STPs) are important signaling systems that mediate biological responses to extracellular stimuli. Some bacterial eSTKs are transmembrane proteins that contain a series of extracellular repeats of the penicillin-binding and Ser/Thr kinase-associated (PASTA) domain, leading to their designation as "PASTA kinases." Enterococcal genomes encode a single PASTA kinase and its cognate phosphatase. Investigations of the enterococcal PASTA kinase revealed its importance in resistance to antibiotics and other cell wall stresses, in enterococcal colonization of the mammalian gut, clues about its mechanism of signal transduction, and its integration with other enterococcal signal transduction systems. In this review, we describe the current state of knowledge of PASTA kinase signaling in enterococci and describe important gaps that still need to be addressed to provide a better understanding of this important signaling system.
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Affiliation(s)
- Dušanka Djorić
- Department of Microbiology and Immunology, Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Nicole E Minton
- Department of Microbiology and Immunology, Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Christopher J Kristich
- Department of Microbiology and Immunology, Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, WI, USA
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12
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Two-Component Signal Transduction Systems in the Human Pathogen Streptococcus agalactiae. Infect Immun 2020; 88:IAI.00931-19. [PMID: 31988177 DOI: 10.1128/iai.00931-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Streptococcus agalactiae (group B Streptococcus [GBS]) is an important cause of invasive infection in newborns, maternal women, and older individuals with underlying chronic illnesses. GBS has many mechanisms to adapt and survive in its host, and these mechanisms are often controlled via two-component signal transduction systems. In GBS, more than 20 distinct two-component systems (TCSs) have been classified to date, consisting of canonical TCSs as well as orphan and atypical sensors and regulators. These signal transducing systems are necessary for metabolic regulation, resistance to antibiotics and antimicrobials, pathogenesis, and adhesion to the mucosal surfaces to colonize the host. This minireview discusses the structures of these TCSs in GBS as well as how selected systems regulate essential cellular processes such as survival and colonization. GBS contains almost double the number of TCSs compared to the closely related Streptococcus pyogenes and Streptococcus pneumoniae, and while research on GBS TCSs has been increasing in recent years, no comprehensive reviews of these TCSs exist, making this review especially relevant.
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13
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Bonne Køhler J, Jers C, Senissar M, Shi L, Derouiche A, Mijakovic I. Importance of protein Ser/Thr/Tyr phosphorylation for bacterial pathogenesis. FEBS Lett 2020; 594:2339-2369. [PMID: 32337704 DOI: 10.1002/1873-3468.13797] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/16/2020] [Accepted: 04/20/2020] [Indexed: 12/13/2022]
Abstract
Protein phosphorylation regulates a large variety of biological processes in all living cells. In pathogenic bacteria, the study of serine, threonine, and tyrosine (Ser/Thr/Tyr) phosphorylation has shed light on the course of infectious diseases, from adherence to host cells to pathogen virulence, replication, and persistence. Mass spectrometry (MS)-based phosphoproteomics has provided global maps of Ser/Thr/Tyr phosphosites in bacterial pathogens. Despite recent developments, a quantitative and dynamic view of phosphorylation events that occur during bacterial pathogenesis is currently lacking. Temporal, spatial, and subpopulation resolution of phosphorylation data is required to identify key regulatory nodes underlying bacterial pathogenesis. Herein, we discuss how technological improvements in sample handling, MS instrumentation, data processing, and machine learning should improve bacterial phosphoproteomic datasets and the information extracted from them. Such information is expected to significantly extend the current knowledge of Ser/Thr/Tyr phosphorylation in pathogenic bacteria and should ultimately contribute to the design of novel strategies to combat bacterial infections.
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Affiliation(s)
- Julie Bonne Køhler
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Carsten Jers
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Mériem Senissar
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Lei Shi
- Systems and Synthetic Biology Division, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Abderahmane Derouiche
- Systems and Synthetic Biology Division, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Ivan Mijakovic
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark.,Systems and Synthetic Biology Division, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
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14
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Hirschfeld C, Gómez-Mejia A, Bartel J, Hentschker C, Rohde M, Maaß S, Hammerschmidt S, Becher D. Proteomic Investigation Uncovers Potential Targets and Target Sites of Pneumococcal Serine-Threonine Kinase StkP and Phosphatase PhpP. Front Microbiol 2020; 10:3101. [PMID: 32117081 PMCID: PMC7011611 DOI: 10.3389/fmicb.2019.03101] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 12/23/2019] [Indexed: 12/17/2022] Open
Abstract
Like eukaryotes, different bacterial species express one or more Ser/Thr kinases and phosphatases that operate in various signaling networks by catalyzing phosphorylation and dephosphorylation of proteins that can immediately regulate biochemical pathways by altering protein function. The human pathogen Streptococcus pneumoniae encodes a single Ser/Thr kinase-phosphatase couple known as StkP-PhpP, which has shown to be crucial in the regulation of cell wall synthesis and cell division. In this study, we applied proteomics to further understand the physiological role of pneumococcal PhpP and StkP with an emphasis on phosphorylation events on Ser and Thr residues. Therefore, the proteome of the non-encapsulated D39 strain (WT), a kinase (ΔstkP), and phosphatase mutant (ΔphpP) were compared in a mass spectrometry based label-free quantification experiment. Results show that a loss of function of PhpP causes an increased abundance of proteins in the phosphate uptake system Pst. Quantitative proteomic data demonstrated an effect of StkP and PhpP on the two-component systems ComDE, LiaRS, CiaRH, and VicRK. To obtain further information on the function, targets and target sites of PhpP and StkP we combined the advantages of phosphopeptide enrichment using titanium dioxide and spectral library based data evaluation for sensitive detection of changes in the phosphoproteome of the wild type and the mutant strains. According to the role of StkP in cell division we identified several proteins involved in cell wall synthesis and cell division that are apparently phosphorylated by StkP. Unlike StkP, the physiological function of the co-expressed PhpP is poorly understood. For the first time we were able to provide a list of previously unknown putative targets of PhpP. Under these new putative targets of PhpP are, among others, five proteins with direct involvement in cell division (DivIVA, GpsB) and peptidoglycan biosynthesis (MltG, MreC, MacP).
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Affiliation(s)
- Claudia Hirschfeld
- Department of Microbial Proteomics, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Alejandro Gómez-Mejia
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, University of Greifswald, Greifswald, Germany
| | - Jürgen Bartel
- Department of Microbial Proteomics, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Christian Hentschker
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Sandra Maaß
- Department of Microbial Proteomics, Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, University of Greifswald, Greifswald, Germany
| | - Dörte Becher
- Department of Microbial Proteomics, Institute of Microbiology, University of Greifswald, Greifswald, Germany
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15
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Park EJ, Kwon YM, Lee JW, Kang HY, Oh JI. Dual control of RegX3 transcriptional activity by SenX3 and PknB. J Biol Chem 2019; 294:11023-11034. [PMID: 31160336 DOI: 10.1074/jbc.ra119.008232] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/30/2019] [Indexed: 01/08/2023] Open
Abstract
The mycobacterial SenX3-RegX3 two-component system consists of the SenX3 sensor histidine kinase and its cognate RegX3 response regulator. This system is a phosphorelay-based regulatory system involved in sensing environmental Pi levels and induction of genes required for Pi acquisition under Pi-limiting conditions. Here we demonstrate that overexpression of the kinase domain of Mycobacterium tuberculosis PknB (PknB-KDMtb) inhibits the transcriptional activity of RegX3 of both M. tuberculosis and Mycobacterium smegmatis (RegX3Mtb and RegX3Ms, respectively). Mass spectrometry results, along with those of in vitro phosphorylation and complementation analyses, revealed that PknB kinase activity inhibits the transcriptional activity of RegX3Mtb through phosphorylation events at Thr-100, Thr-191, and Thr-217. Electrophoretic mobility shift assays disclosed that phosphorylation of Thr-191 and Thr-217 abolishes the DNA-binding ability of RegX3Mtb and that Thr-100 phosphorylation likely prevents RegX3Mtb from being activated through conformational changes induced by SenX3-mediated phosphorylation. We propose that the convergence of the PknB and SenX3-RegX3 signaling pathways might enable mycobacteria to integrate environmental Pi signals with the cellular replication state to adjust gene expression in response to Pi availability.
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Affiliation(s)
- Eun-Jin Park
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea
| | - Yu-Mi Kwon
- Biomedical Research Institute, Center for Theragnosis, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea, and; Department of Life Science and Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - Jin-Won Lee
- Department of Life Science and Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - Ho-Young Kang
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea
| | - Jeong-Il Oh
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea,.
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16
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Janczarek M, Vinardell JM, Lipa P, Karaś M. Hanks-Type Serine/Threonine Protein Kinases and Phosphatases in Bacteria: Roles in Signaling and Adaptation to Various Environments. Int J Mol Sci 2018; 19:ijms19102872. [PMID: 30248937 PMCID: PMC6213207 DOI: 10.3390/ijms19102872] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 09/17/2018] [Accepted: 09/19/2018] [Indexed: 12/19/2022] Open
Abstract
Reversible phosphorylation is a key mechanism that regulates many cellular processes in prokaryotes and eukaryotes. In prokaryotes, signal transduction includes two-component signaling systems, which involve a membrane sensor histidine kinase and a cognate DNA-binding response regulator. Several recent studies indicate that alternative regulatory pathways controlled by Hanks-type serine/threonine kinases (STKs) and serine/threonine phosphatases (STPs) also play an essential role in regulation of many different processes in bacteria, such as growth and cell division, cell wall biosynthesis, sporulation, biofilm formation, stress response, metabolic and developmental processes, as well as interactions (either pathogenic or symbiotic) with higher host organisms. Since these enzymes are not DNA-binding proteins, they exert the regulatory role via post-translational modifications of their protein targets. In this review, we summarize the current knowledge of STKs and STPs, and discuss how these enzymes mediate gene expression in prokaryotes. Many studies indicate that regulatory systems based on Hanks-type STKs and STPs play an essential role in the regulation of various cellular processes, by reversibly phosphorylating many protein targets, among them several regulatory proteins of other signaling cascades. These data show high complexity of bacterial regulatory network, in which the crosstalk between STK/STP signaling enzymes, components of TCSs, and the translational machinery occurs. In this regulation, the STK/STP systems have been proved to play important roles.
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Affiliation(s)
- Monika Janczarek
- Department of Genetics and Microbiology, Institute of Microbiology and Biotechnology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
| | - José-María Vinardell
- Department of Microbiology, Faculty of Biology, University of Sevilla, Avda. Reina Mercedes 6, 41012 Sevilla, Spain.
| | - Paulina Lipa
- Department of Genetics and Microbiology, Institute of Microbiology and Biotechnology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
| | - Magdalena Karaś
- Department of Genetics and Microbiology, Institute of Microbiology and Biotechnology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
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17
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Mutation in the pssZ Gene Negatively Impacts Exopolysaccharide Synthesis, Surface Properties, and Symbiosis of Rhizobium leguminosarum bv. trifolii with Clover. Genes (Basel) 2018; 9:genes9070369. [PMID: 30041474 PMCID: PMC6071215 DOI: 10.3390/genes9070369] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 07/05/2018] [Accepted: 07/16/2018] [Indexed: 12/19/2022] Open
Abstract
Rhizobium leguminosarum bv. trifolii is a soil bacterium capable of establishing a nitrogen-fixing symbiosis with clover plants (Trifolium spp.). This bacterium secretes large amounts of acidic exopolysaccharide (EPS), which plays an essential role in the symbiotic interaction with the host plant. This polymer is biosynthesized by a multi-enzymatic complex located in the bacterial inner membrane, whose components are encoded by a large chromosomal gene cluster, called Pss-I. In this study, we characterize R. leguminosarum bv. trifolii strain Rt297 that harbors a Tn5 transposon insertion located in the pssZ gene from the Pss-I region. This gene codes for a protein that shares high identity with bacterial serine/threonine protein phosphatases. We demonstrated that the pssZ mutation causes pleiotropic effects in rhizobial cells. Strain Rt297 exhibited several physiological and symbiotic defects, such as lack of EPS production, reduced growth kinetics and motility, altered cell-surface properties, and failure to infect the host plant. These data indicate that the protein encoded by the pssZ gene is indispensable for EPS synthesis, but also required for proper functioning of R. leguminosarum bv. trifolii cells.
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18
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Ni H, Fan W, Li C, Wu Q, Hou H, Hu D, Zheng F, Zhu X, Wang C, Cao X, Shao ZQ, Pan X. Streptococcus suis DivIVA Protein Is a Substrate of Ser/Thr Kinase STK and Involved in Cell Division Regulation. Front Cell Infect Microbiol 2018; 8:85. [PMID: 29616196 PMCID: PMC5869912 DOI: 10.3389/fcimb.2018.00085] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 03/02/2018] [Indexed: 12/14/2022] Open
Abstract
Streptococcus suis serotype 2 is an important swine pathogen and an emerging zoonotic agent that causes severe infections. Recent studies have reported a eukaryotic-like Ser/Thr protein kinase (STK) gene and characterized its role in the growth and virulence of different S. suis 2 strains. In the present study, phosphoproteomic analysis was adopted to identify substrates of the STK protein. Seven proteins that were annotated to participate in different cell processes were identified as potential substrates, which suggests the pleiotropic effects of stk on S. suis 2 by targeting multiple pathways. Among them, a protein characterized as cell division initiation protein (DivIVA) was further investigated. In vitro analysis demonstrated that the recombinant STK protein directly phosphorylates threonine at amino acid position 199 (Thr-199) of DivIVA. This effect could be completely abolished by the T199A mutation. To determine the specific role of DivIVA in growth and division, a divIVA mutant was constructed. The ΔdivIVA strain exhibited impaired growth and division, including lower viability, enlarged cell mass, asymmetrical division caused by aberrant septum, and extremely weak pathogenicity in a mouse infection model. Collectively, our results reveal that STK regulates the cell growth and virulence of S. suis 2 by targeting substrates that are involved in different biological pathways. The inactivation of DivIVA leads to severe defects in cell division and strongly attenuates pathogenicity, thereby indicating its potential as a molecular drug target against S. suis.
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Affiliation(s)
- Hua Ni
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,School of Life Sciences, Nanjing Normal University, Nanjing, China.,The Key Laboratory of Ecology and Biological Resources in Yarkand Oasis at Colleges and Universities Under the Department of Education of Xinjiang Uygur Autonomous Region, Kashgar University, Kashgar, China
| | - Weiwei Fan
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,Department of Pharmacy, Changzhou Wujin People's Hospital, Changzhou, China
| | - Chaolong Li
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Qianqian Wu
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Hongfen Hou
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Dan Hu
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Feng Zheng
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Xuhui Zhu
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Changjun Wang
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Xiangrong Cao
- School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Zhu-Qing Shao
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Xiuzhen Pan
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,School of Life Sciences, Nanjing Normal University, Nanjing, China
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19
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Khara P, Mohapatra SS, Biswas I. Role of CovR phosphorylation in gene transcription in Streptococcus mutans. MICROBIOLOGY-SGM 2018; 164:704-715. [PMID: 29504927 DOI: 10.1099/mic.0.000641] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Streptococcus mutans, the primary aetiological agent of dental caries, is one of the major bacteria of the human oral cavity. The pathogenicity of this bacterium is attributed not only to the expression of virulence factors, but also to its ability to respond and adapt rapidly to the ever-changing conditions of the oral cavity. The two-component signal transduction system (TCS) CovR/S plays a crucial role in virulence and stress response in many streptococci. Surprisingly, in S. mutans the response regulator CovR appears to be an orphan, as the cognate sensor kinase, CovS, is absent in all the strains. We found that acetyl phosphate, an intracellular phosphodonor molecule known to act in signalling, might play a role in CovR phosphorylation in vivo. We also found that in vitro, upon phosphorylation by potassium phosphoramide (a high-energy phophodonor) CovR formed a dimer and showed altered electrophoretic mobility. As expected, we found that the conserved aspartic acid residue at position 53 (D53) was the site of phosphorylation, since neither phosphorylation nor dimerization was seen when an alanine-substituted CovR mutant (D53A) was used. Surprisingly, we found that the ability of CovR to act as a transcriptional regulator does not depend upon its phosphorylation status, since the D53A mutant behaved similarly to the wild-type protein in both in vivo and in vitro DNA-binding assays. This unique phosphorylation-mediated inhibition of CovR function in S. mutans sheds light on an unconventional mechanism of the signal transduction pathway.
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Affiliation(s)
- Pratick Khara
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Saswat Sourav Mohapatra
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, USA.,Present address: Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, TN 603203, India
| | - Indranil Biswas
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, USA
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20
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Mattos-Graner RO, Duncan MJ. Two-component signal transduction systems in oral bacteria. J Oral Microbiol 2017; 9:1400858. [PMID: 29209465 PMCID: PMC5706477 DOI: 10.1080/20002297.2017.1400858] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 11/01/2017] [Indexed: 01/03/2023] Open
Abstract
We present an overview of how members of the oral microbiota respond to their environment by regulating gene expression through two-component signal transduction systems (TCSs) to support conditions compatible with homeostasis in oral biofilms or drive the equilibrium toward dysbiosis in response to environmental changes. Using studies on the sub-gingival Gram-negative anaerobe Porphyromonas gingivalis and Gram-positive streptococci as examples, we focus on the molecular mechanisms involved in activation of TCS and species specificities of TCS regulons.
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Affiliation(s)
- Renata O. Mattos-Graner
- Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas – UNICAMP, São Paulo, Brazil
| | - Margaret J. Duncan
- Department of Oral Medicine, Infection and Immunity, The Forsyth Institute, Cambridge, MA, USA
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21
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Kant S, Asthana S, Missiakas D, Pancholi V. A novel STK1-targeted small-molecule as an "antibiotic resistance breaker" against multidrug-resistant Staphylococcus aureus. Sci Rep 2017; 7:5067. [PMID: 28698584 PMCID: PMC5505960 DOI: 10.1038/s41598-017-05314-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 06/15/2017] [Indexed: 01/28/2023] Open
Abstract
Ser/Thr protein kinase (STK1) plays a critical role in cell wall biosynthesis of and drug resistance in methicillin-resistant Staphylococcus aureus (MRSA). MRSA strains lacking STK1 become susceptible to failing cephalosporins, such as Ceftriaxone and Cefotaxime. STK1, despite being nonessential protein for MRSA survival, it can serve as an important therapeutic agent for combination therapy. Here, we report a novel small molecule quinazoline compound, Inh2-B1, which specifically inhibits STK1 activity by directly binding to its ATP-binding catalytic domain. Functional analyses encompassing in vitro growth inhibition of MRSA, and in vivo protection studies in mice against the lethal MRSA challenge indicated that at high concentration neither Inh2-B1 nor Ceftriaxone or Cefotaxime alone was able to inhibit the growth of bacteria or protect the challenged mice. However, the growth of MRSA was inhibited, and a significant protection in mice against the bacterial challenge was observed at a micromolar concentration of Ceftriaxone or Cefotaxime in the presence of Inh2-B1. Cell-dependent minimal to no toxicity of Inh2-B1, and its abilities to down-regulate cell wall hydrolase genes and disrupt the biofilm formation of MRSA clearly indicated that Inh2-B1 serves as a therapeutically important “antibiotic-resistance-breaker,” which enhances the bactericidal activity of Ceftriaxone/Cefotaxime against highly pathogenic MRSA infection.
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Affiliation(s)
- Sashi Kant
- Department of Pathology, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Shailendra Asthana
- Drug Discovery Research Center, Translational Health Science and Technology Institute, Faridabad-Gurgaon Expressway, Haryana, India
| | | | - Vijay Pancholi
- Department of Pathology, The Ohio State University College of Medicine, Columbus, Ohio, USA.
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Stamsås GA, Straume D, Salehian Z, Håvarstein LS. Evidence that pneumococcal WalK is regulated by StkP through protein-protein interaction. MICROBIOLOGY-SGM 2017; 163:383-399. [PMID: 27902439 DOI: 10.1099/mic.0.000404] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
WalRK is the only two-component regulatory system essential for viability in Streptococcus pneumoniae. Despite its importance, the biological role of this system is not well understood. However, previous studies have shown that it has a crucial role in controlling pneumococcal cell division. Considerable efforts have been made to understand how the WalRK system is regulated, but no signal(s) sensed by the WalK histidine kinase has been identified so far. Here, we provide evidence that the serine/threonine protein kinase StkP modulates the activity of WalK through direct protein-protein interaction, suggesting that this interaction is one of the signals sensed by WalK. In most low-G+C content Gram-positive bacteria, WalK orthologues are attached to the cytoplasmic membrane via two transmembrane segments separated by a large extracellular loop believed to function as a sensor domain. In contrast, members of the genus Streptococcus have WalK histidine kinases that are anchored to the cytoplasmic membrane by a single transmembrane segment. It has been a long-standing question whether this segment only serves as a membrane anchor or if it also functions as a signal-sensing domain. Our data strongly support the latter, i.e. that the transmembrane segment senses signals that regulate the activity of WalK.
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Affiliation(s)
- Gro Anita Stamsås
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, NO-1432 Ås, Norway
| | - Daniel Straume
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, NO-1432 Ås, Norway
| | - Zhian Salehian
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, NO-1432 Ås, Norway
| | - Leiv Sigve Håvarstein
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, NO-1432 Ås, Norway
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Roobthaisong A, Aikawa C, Nozawa T, Maruyama F, Nakagawa I. YvqE and CovRS of Group A Streptococcus Play a Pivotal Role in Viability and Phenotypic Adaptations to Multiple Environmental Stresses. PLoS One 2017; 12:e0170612. [PMID: 28122066 PMCID: PMC5266302 DOI: 10.1371/journal.pone.0170612] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 01/06/2017] [Indexed: 01/14/2023] Open
Abstract
Streptococcus pyogenes (group A Streptococcus, or GAS) is a human pathogen that causes a wide range of diseases. For successful colonization within a variety of host niches, GAS utilizes TCSs to sense and respond to environmental changes and adapts its pathogenic traits accordingly; however, many GAS TCSs and their interactions remain uncharacterized. Here, we elucidated the roles of a poorly characterized TCS, YvqEC, and a well-studied TCS, CovRS, in 2 different GAS strain SSI-1 and JRS4, respectively. Deletion of yvqE and yvqC in JRS4 resulted in lower cell viability and abnormality of cell division when compared to the wild-type strain under standard culture conditions, demonstrating an important role for YvqEC. Furthermore, a double-deletion of yvqEC and covRS in SSI-1 and JRS4 resulted in a significantly impaired ability to survive under various stress conditions, as well as an increased sensitivity to cell wall-targeting antibiotics compared to that observed in either single mutant or wild-type strains suggesting synergistic interactions. Our findings provide new insights into the impact of poorly characterized TCS (YvqEC) and potential synergistic interactions between YvqEC and CovRS and reveal their potential role as novel therapeutic targets against GAS infection.
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Affiliation(s)
- Amonrattana Roobthaisong
- Section of Molecular Craniofacial Embryology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Chihiro Aikawa
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takashi Nozawa
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Fumito Maruyama
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Ichiro Nakagawa
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
- * E-mail:
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Edgar RJ, Chen J, Kant S, Rechkina E, Rush JS, Forsberg LS, Jaehrig B, Azadi P, Tchesnokova V, Sokurenko EV, Zhu H, Korotkov KV, Pancholi V, Korotkova N. SpyB, a Small Heme-Binding Protein, Affects the Composition of the Cell Wall in Streptococcus pyogenes. Front Cell Infect Microbiol 2016; 6:126. [PMID: 27790410 PMCID: PMC5061733 DOI: 10.3389/fcimb.2016.00126] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 09/27/2016] [Indexed: 12/01/2022] Open
Abstract
Streptococcus pyogenes (Group A Streptococcus or GAS) is a hemolytic human pathogen associated with a wide variety of infections ranging from minor skin and throat infections to life-threatening invasive diseases. The cell wall of GAS consists of peptidoglycan sacculus decorated with a carbohydrate comprising a polyrhamnose backbone with immunodominant N-acetylglucosamine side-chains. All GAS genomes contain the spyBA operon, which encodes a 35-amino-acid membrane protein SpyB, and a membrane-bound C3-like ADP-ribosyltransferase SpyA. In this study, we addressed the function of SpyB in GAS. Phenotypic analysis of a spyB deletion mutant revealed increased bacterial aggregation, and reduced sensitivity to β-lactams of the cephalosporin class and peptidoglycan hydrolase PlyC. Glycosyl composition analysis of cell wall isolated from the spyB mutant suggested an altered carbohydrate structure compared with the wild-type strain. Furthermore, we found that SpyB associates with heme and protoporphyrin IX. Heme binding induces SpyB dimerization, which involves disulfide bond formation between the subunits. Thus, our data suggest the possibility that SpyB activity is regulated by heme.
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Affiliation(s)
- Rebecca J. Edgar
- Department of Molecular and Cellular Biochemistry, University of KentuckyLexington, KY, USA
| | - Jing Chen
- Department of Molecular and Cellular Biochemistry, University of KentuckyLexington, KY, USA
| | - Sashi Kant
- Department of Pathology, Ohio State UniversityColumbus, OH, USA
| | - Elena Rechkina
- Department of Microbiology, University of WashingtonSeattle, WA, USA
| | - Jeffrey S. Rush
- Department of Molecular and Cellular Biochemistry, University of KentuckyLexington, KY, USA
| | | | - Bernhard Jaehrig
- Complex Carbohydrate Research Center, University of GeorgiaAthens, GA, USA
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of GeorgiaAthens, GA, USA
| | | | | | - Haining Zhu
- Department of Molecular and Cellular Biochemistry, University of KentuckyLexington, KY, USA
| | - Konstantin V. Korotkov
- Department of Molecular and Cellular Biochemistry, University of KentuckyLexington, KY, USA
| | - Vijay Pancholi
- Department of Pathology, Ohio State UniversityColumbus, OH, USA
| | - Natalia Korotkova
- Department of Molecular and Cellular Biochemistry, University of KentuckyLexington, KY, USA
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25
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Abstract
Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the "stressome" of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance.
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26
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Sajid A, Arora G, Singhal A, Kalia VC, Singh Y. Protein Phosphatases of Pathogenic Bacteria: Role in Physiology and Virulence. Annu Rev Microbiol 2015; 69:527-47. [DOI: 10.1146/annurev-micro-020415-111342] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Andaleeb Sajid
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
| | - Gunjan Arora
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
| | - Anshika Singhal
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
| | - Vipin C. Kalia
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
| | - Yogendra Singh
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
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Wright DP, Ulijasz AT. Regulation of transcription by eukaryotic-like serine-threonine kinases and phosphatases in Gram-positive bacterial pathogens. Virulence 2015; 5:863-85. [PMID: 25603430 PMCID: PMC4601284 DOI: 10.4161/21505594.2014.983404] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Bacterial eukaryotic-like serine threonine kinases (eSTKs) and serine threonine phosphatases (eSTPs) have emerged as important signaling elements that are indispensable for pathogenesis. Differing considerably from their histidine kinase counterparts, few eSTK genes are encoded within the average bacterial genome, and their targets are pleiotropic in nature instead of exclusive. The growing list of important eSTK/P substrates includes proteins involved in translation, cell division, peptidoglycan synthesis, antibiotic tolerance, resistance to innate immunity and control of virulence factors. Recently it has come to light that eSTK/Ps also directly modulate transcriptional machinery in many microbial pathogens. This novel form of regulation is now emerging as an additional means by which bacteria can alter their transcriptomes in response to host-specific environmental stimuli. Here we focus on the ability of eSTKs and eSTPs in Gram-positive bacterial pathogens to directly modulate transcription, the known mechanistic outcomes of these modifications, and their roles as an added layer of complexity in controlling targeted RNA synthesis to enhance virulence potential.
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Key Words
- OCS, one-component signaling
- PASTA, penicillin-binding protein and Ser/Thr kinase associated
- PPM, protein phosphatase metal binding
- PTM, posttranslational modification
- REC, receiver
- ROS, reactive oxygen species
- TCS, two-component signaling
- bacteria
- eSTK, eukaryotic-like serine-threonine kinase
- eSTP, eukaryotic-like serine-threonine phosphatase
- infection
- phosphorylation
- serine threonine kinase
- serine threonine phosphatase
- transcription
- wHTH, winged helix-turn-helix
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Affiliation(s)
- David P Wright
- a MRC Centre for Molecular Bacteriology and Infection (CMBI); Imperial College London ; London , UK
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28
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Consequences of the variability of the CovRS and RopB regulators among Streptococcus pyogenes causing human infections. Sci Rep 2015; 5:12057. [PMID: 26174161 PMCID: PMC4502508 DOI: 10.1038/srep12057] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 06/05/2015] [Indexed: 11/08/2022] Open
Abstract
To evaluate the importance of covRS and ropB mutations in invasive disease caused by Group A Streptococci (GAS), we determined the sequence of the covRS and ropB genes of 191 isolates from invasive infections and pharyngitis, comprising a diverse set of emm types and multilocus sequence types. The production of SpeB and the activity of NAD glycohydrolase (NADase) and streptolysin S (SLS) were evaluated. The results support the acquisition of null covS alleles (predicted to eliminate protein function), resulting in downregulation of SpeB and upregulation of NADase and SLS, as a mechanism possibly contributing to higher invasiveness. Among the isolates tested, this mechanism was found to be uncommon (10% of invasive isolates) and was not more prevalent among clones with enhanced invasiveness (including M1T1) but occurred in diverse genetic backgrounds. In lineages such as emm64, these changes did not result in upregulation of NADase and SLS, highlighting the diversity of regulatory pathways in GAS. Despite abrogating SpeB production, null alleles in ropB were not associated with invasive infection. The covRS and ropB genes are under stabilising selection and no expansion of isolates carrying null alleles has been observed, suggesting that the presence of these regulators is important for overall fitness.
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29
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Herbert JA, Mitchell AM, Mitchell TJ. A Serine-Threonine Kinase (StkP) Regulates Expression of the Pneumococcal Pilus and Modulates Bacterial Adherence to Human Epithelial and Endothelial Cells In Vitro. PLoS One 2015; 10:e0127212. [PMID: 26090876 PMCID: PMC4474723 DOI: 10.1371/journal.pone.0127212] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 04/02/2015] [Indexed: 12/25/2022] Open
Abstract
The pneumococcal serine threonine protein kinase (StkP) acts as a global regulator in the pneumococcus. Bacterial mutants deficient in StkP are less virulent in animal models of infection. The gene for this regulator is located adjacent to the gene for its cognate phosphatase in the pneumococcal genome. The phosphatase dephosphorylates proteins phosphorylated by StkP and has been shown to regulate a number of key pneumococcal virulence factors and to modulate adherence to eukaryotic cells. The role of StkP in adherence of pneumococci to human cells has not previously been reported. In this study we show StkP represses the pneumococcal pilus, a virulence factor known to be important for bacterial adhesion. In a serotype 4 strain regulation of the pilus by StkP modulates adherence to human brain microvascular endothelial cells (HBMEC) and human lung epithelial cells. This suggests that the pneumococcal pilus may play a role in adherence during infections such as meningitis and pneumonia. We show that regulation of the pilus occurs at the population level as StkP alters the number of pili-positive cells within a single culture. As far as we are aware this is the first gene identified outside of the pilus islet that regulates the biphasic expression of the pilus. These findings suggest StkPs role in cell division may be linked to regulation of expression of a cell surface adhesin.
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Affiliation(s)
- Jenny A. Herbert
- Institute of Microbiology and Infection, School of Immunity and Infection, University of Birmingham, Birmingham, England, United Kingdom
| | - Andrea M. Mitchell
- Institute of Microbiology and Infection, School of Immunity and Infection, University of Birmingham, Birmingham, England, United Kingdom
| | - Timothy J. Mitchell
- Institute of Microbiology and Infection, School of Immunity and Infection, University of Birmingham, Birmingham, England, United Kingdom
- * E-mail:
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30
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Kant S, Agarwal S, Pancholi P, Pancholi V. TheStreptococcus pyogenesorphan protein tyrosine phosphatase, SP-PTP, possesses dual specificity and essential virulence regulatory functions. Mol Microbiol 2015; 97:515-40. [DOI: 10.1111/mmi.13047] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/30/2015] [Indexed: 01/06/2023]
Affiliation(s)
- Sashi Kant
- Department of Pathology; The Ohio State University College of Medicine; Wexner Medical Center; Columbus OH USA
| | - Shivani Agarwal
- Department of Pathology; The Ohio State University College of Medicine; Wexner Medical Center; Columbus OH USA
| | - Preeti Pancholi
- Department of Pathology; The Ohio State University College of Medicine; Wexner Medical Center; Columbus OH USA
| | - Vijay Pancholi
- Department of Pathology; The Ohio State University College of Medicine; Wexner Medical Center; Columbus OH USA
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Characterization of the effect of the histidine kinase CovS on response regulator phosphorylation in group A Streptococcus. Infect Immun 2015; 83:1068-77. [PMID: 25561708 DOI: 10.1128/iai.02659-14] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Two-component gene regulatory systems (TCSs) are a major mechanism by which bacteria respond to environmental stimuli and thus are critical to infectivity. For example, the control of virulence regulator/sensor kinase (CovRS) TCS is central to the virulence of the major human pathogen group A Streptococcus (GAS). Here, we used a combination of quantitative in vivo phosphorylation assays, isoallelic strains that varied by only a single amino acid in CovS, and transcriptome analyses to characterize the impact of CovS on CovR phosphorylation and GAS global gene expression. We discovered that CovS primarily serves to phosphorylate CovR, thereby resulting in the repression of virulence factor-encoding genes. However, a GAS strain selectively deficient in CovS phosphatase activity had a distinct transcriptome relative to that of its parental strain, indicating that both CovS kinase and phosphatase activities influence the CovR phosphorylation status. Surprisingly, compared to a serotype M3 strain, serotype M1 GAS strains had high levels of phosphorylated CovR, low transcript levels of CovR-repressed genes, and strikingly different responses to environmental cues. Moreover, the inactivation of CovS in the serotype M1 background resulted in a greater decrease in phosphorylated CovR levels and a greater increase in the transcript levels of CovR-repressed genes than did CovS inactivation in a serotype M3 strain. These data clarify the influence of CovS on the CovR phosphorylation status and provide insight into why serotype M1 GAS strains have high rates of spontaneous mutations in covS during invasive GAS infection, thus providing a link between TCS molecular function and the epidemiology of deadly bacterial infections.
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32
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Streptococcus pyogenes polymyxin B-resistant mutants display enhanced ExPortal integrity. J Bacteriol 2014; 196:2563-77. [PMID: 24794568 DOI: 10.1128/jb.01596-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The ExPortal protein secretion organelle in Streptococcus pyogenes is an anionic phospholipid-containing membrane microdomain enriched in Sec translocons and postsecretion protein biogenesis factors. Polymyxin B binds to and disrupts ExPortal integrity, resulting in defective secretion of several toxins. To gain insight into factors that influence ExPortal organization, a genetic screen was conducted to select for spontaneous polymyxin B-resistant mutants displaying enhanced ExPortal integrity. Whole-genome resequencing of 25 resistant mutants revealed from one to four mutations per mutant genome clustered primarily within a core set of 10 gene groups. Construction of mutants with individual deletions or insertions demonstrated that 7 core genes confer resistance and enhanced ExPortal integrity through loss of function, while 3 were likely due to gain of function and/or combinatorial effects. Core resistance genes include a transcriptional regulator of lipid biosynthesis, several genes involved in nutrient acquisition, and a variety of genes involved in stress responses. Two members of the latter class also function as novel regulators of the secreted SpeB cysteine protease. Analysis of the most frequently isolated mutation, a single nucleotide deletion in a track of 9 consecutive adenine residues in pstS, encoding a component of a high-affinity Pi transporter, suggests that this sequence functions as a molecular switch to facilitate stress adaptation. Together, these data suggest the existence of a membrane stress response that promotes enhanced ExPortal integrity and resistance to cationic antimicrobial peptides.
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33
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Dual-site phosphorylation of the control of virulence regulator impacts group a streptococcal global gene expression and pathogenesis. PLoS Pathog 2014; 10:e1004088. [PMID: 24788524 PMCID: PMC4006921 DOI: 10.1371/journal.ppat.1004088] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 03/10/2014] [Indexed: 11/20/2022] Open
Abstract
Phosphorylation relays are a major mechanism by which bacteria alter transcription in response to environmental signals, but understanding of the functional consequences of bacterial response regulator phosphorylation is limited. We sought to characterize how phosphorylation of the control of virulence regulator (CovR) protein from the major human pathogen group A Streptococcus (GAS) influences GAS global gene expression and pathogenesis. CovR mainly serves to repress GAS virulence factor-encoding genes and has been shown to homodimerize following phosphorylation on aspartate-53 (D53) in vitro. We discovered that CovR is phosphorylated in vivo and that such phosphorylation is partially heat-stable, suggesting additional phosphorylation at non-aspartate residues. Using mass spectroscopy along with targeted mutagenesis, we identified threonine-65 (T65) as an additional CovR phosphorylation site under control of the serine/threonine kinase (Stk). Phosphorylation on T65, as mimicked by the recombinant CovR T65E variant, abolished in vitro CovR D53 phosphorylation. Similarly, isoallelic GAS strains that were either unable to be phosphorylated at D53 (CovR-D53A) or had functional constitutive phosphorylation at T65 (CovR-T65E) had essentially an identical gene repression profile to each other and to a CovR-inactivated strain. However, the CovR-D53A and CovR-T65E isoallelic strains retained the ability to positively influence gene expression that was abolished in the CovR-inactivated strain. Consistent with these observations, the CovR-D53A and CovR-T65E strains were hypervirulent compared to the CovR-inactivated strain in a mouse model of invasive GAS disease. Surprisingly, an isoalleic strain unable to be phosphorylated at CovR T65 (CovR-T65A) was hypervirulent compared to the wild-type strain, as auto-regulation of covR gene expression resulted in lower covR gene transcript and CovR protein levels in the CovR-T65A strain. Taken together, these data establish that CovR is phosphorylated in vivo and elucidate how the complex interplay between CovR D53 activating phosphorylation, T65 inhibiting phosphorylation, and auto-regulation impacts streptococcal host-pathogen interaction. Group A Streptococcus (GAS) causes a variety of human diseases ranging from mild throat infections to deadly invasive infections. The capacity of GAS to cause infections at such diverse locations is dependent on its ability to precisely control the production of a broad variety of virulence factors. The control of virulence regulator (CovR) is a master regulator of GAS genes encoding virulence factors. It is known that CovR can be phosphorylated on aspartate-53 in vitro and that such phosphorylation increases its regulatory activity, but what additional factors influence CovR-mediated gene expression have not been established. Herein we show for the first time that CovR is phosphorylated in vivo and that phosphorylation of CovR on threonine-65 by the threonine/serine kinase Stk prevents aspartate-53 phosphorylation, thereby decreasing CovR regulatory activity. Further, while CovR-mediated gene repression is highly dependent on aspartate-53 phosphorylation, CovR-mediated gene activation proceeds via a phosphorylation-independent mechanism. Modifications in CovR phosphorylation sites significantly affected the expression of GAS virulence factors during infection and markedly altered the ability of GAS to cause disease in mice. These data establish that multiple inter-related pathways converge to influence CovR phosphorylation, thereby providing new insight into the complex regulatory network used by GAS during infection.
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Tatsuno I, Isaka M, Okada R, Zhang Y, Hasegawa T. Relevance of the two-component sensor protein CiaH to acid and oxidative stress responses in Streptococcus pyogenes. BMC Res Notes 2014; 7:189. [PMID: 24673808 PMCID: PMC3986815 DOI: 10.1186/1756-0500-7-189] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 03/17/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The production of virulence proteins depends on environmental factors, and two-component regulatory systems are involved in sensing these factors. We previously established knockout strains in all suspected two-component regulatory sensor proteins of the emm1 clinical strain of S. pyogenes and examined their relevance to acid stimuli in a natural atmosphere. In the present study, their relevance to acid stimuli was re-examined in an atmosphere containing 5% CO2. RESULTS The spy1236 (which is identical to ciaHpy) sensor knockout strain showed significant growth reduction compared with the parental strain in broth at pH 6.0, suggesting that the Spy1236 (CiaHpy) two-component sensor protein is involved in acid response of S. pyogenes. CiaH is also conserved in Streptococcus pneumoniae, and it has been reported that deletion of the gene for its cognate response regulator (ciaRpn) made the pneumococcal strains more sensitive to oxidative stress. In this report, we show that the spy1236 knockout mutant of S. pyogenes is more sensitive to oxidative stress than the parental strain. CONCLUSIONS These results suggest that the two-component sensor protein CiaH is involved in stress responses in S. pyogenes.
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Affiliation(s)
| | | | | | | | - Tadao Hasegawa
- Department of Bacteriology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi Mizuho-cho Mizuho-ku, Nagoya 467-8601, Japan.
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35
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Massidda O, Nováková L, Vollmer W. From models to pathogens: how much have we learned about Streptococcus pneumoniae cell division? Environ Microbiol 2013; 15:3133-57. [PMID: 23848140 DOI: 10.1111/1462-2920.12189] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 06/08/2013] [Accepted: 06/09/2013] [Indexed: 12/22/2022]
Abstract
Streptococcus pneumoniae is an oval-shaped Gram-positive coccus that lives in intimate association with its human host, both as a commensal and pathogen. The seriousness of pneumococcal infections and the spread of multi-drug resistant strains call for new lines of intervention. Bacterial cell division is an attractive target to develop antimicrobial drugs. This review discusses the recent advances in understanding S. pneumoniae growth and division, in comparison with the best studied rod-shaped models, Escherichia coli and Bacillus subtilis. To maintain their shape, these bacteria propagate by peripheral and septal peptidoglycan synthesis, involving proteins that assemble into distinct complexes called the elongasome and the divisome, respectively. Many of these proteins are conserved in S. pneumoniae, supporting the notion that the ovococcal shape is also achieved by rounds of elongation and division. Importantly, S. pneumoniae and close relatives with similar morphology differ in several aspects from the model rods. Overall, the data support a model in which a single large machinery, containing both the peripheral and septal peptidoglycan synthesis complexes, assembles at midcell and governs growth and division. The mechanisms generating the ovococcal or coccal shape in lactic-acid bacteria have likely evolved by gene reduction from a rod-shaped ancestor of the same group.
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Affiliation(s)
- Orietta Massidda
- Department of Surgical Sciences, University of Cagliari, Via Porcell, 4, 09100, Cagliari, Italy
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36
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Tatsuno I, Okada R, Zhang Y, Isaka M, Hasegawa T. Partial loss of CovS function in Streptococcus pyogenes causes severe invasive disease. BMC Res Notes 2013; 6:126. [PMID: 23537349 PMCID: PMC3637574 DOI: 10.1186/1756-0500-6-126] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 03/20/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND CovRS (or CsrRS) is a two-component regulatory system that regulates the production of multiple virulence factors in Streptococcus pyogenes. covS mutations are often found in isolates recovered from mice that have been experimentally infected with S. pyogenes and covS mutations enhance bacterial virulence in an invasive infection mouse model. In addition, covS mutations were detected more frequently in a panel of clinical isolates from severe invasive streptococcal infections than those from non-severe infections. Thus, covS mutations may be associated with the onset of severe invasive infections. RESULTS Known covS mutations were divided into two groups: (i) frameshift mutations that caused a deletion of functional regions and (ii) point mutations that caused single (or double) amino acid(s) substitutions. Frameshift mutations are frequent in mouse-passaged isolates, whereas point mutations are frequent in clinical isolates. The functions of CovS proteins with a single amino acid substitution in clinical isolates were estimated based on the streptococcal pyrogenic exotoxin B (SpeB) production and NAD+-glycohydrolase (NADase) activity, which are known to be regulated by the CovRS system. Point mutations partially, but not completely, impaired the function of the covS alleles. We also investigated some of the benefits that a partial loss of function in covS alleles with point mutations might confer on clinical isolates. We found that covS knockout mutants (ΔcovS strains) had an impaired growth ability in a normal atmosphere in Todd Hewitt broth compared with parental isolates having wild-type or point-mutated covS. CONCLUSIONS The loss of CovS proteins in S. pyogenes may confer greater virulence, but bacteria may also lose the ability to respond to certain external signals recognized by CovS. Therefore, point mutations that retain the function of CovS and confer hypervirulence may have natural selective advantages.
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Affiliation(s)
- Ichiro Tatsuno
- Department of Bacteriology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi Mizuho-cho Mizuho-ku, Nagoya 467-8601, Japan
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Martinez MA, Das K, Saikolappan S, Materon LA, Dhandayuthapani S. A serine/threonine phosphatase encoded by MG_207 of Mycoplasma genitalium is critical for its virulence. BMC Microbiol 2013; 13:44. [PMID: 23432936 PMCID: PMC3639085 DOI: 10.1186/1471-2180-13-44] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 02/19/2013] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Bacterial signal transduction systems like two component system (TCS) and Serine/Threonine kinase (STK) and Serine/Threonine phosphatase (STP) play important roles in the virulence and pathogenesis of bacterial pathogens. Mycoplasma genitalium, a mollicute that causes the urogenital diseases urethritis and cervicitis in men and women, respectively, is a pathogen which lacks TCS but possesses STK/STP. In this study, we investigated the biochemical and virulence properties of an STP protein encoded by the gene MG_207 of this species. RESULTS We overexpressed MG207 in Escherichia coli overexpression system as a recombinant His10MG207 protein and purified it with affinity chromatography. This recombinant protein readily hydrolyzed the substrate p-nitrophenyl phosphate (pNPP) in a dose-dependent manner. Additional studies using synthetic peptides as substrates revealed that the recombinant protein was able to hydrolyze the threonine phosphate. Further, a transposon insertion mutant strain of M. genitalium (TIM207) that lacks the protein MG207 showed differentially phosphorylated proteins when compared to the wild type G37 strain. Mass spectrometry revealed that some of the key proteins differentially phosphorylated in TIM207 strain were putative cytoskeletal protein encoded by the gene MG_328 and pyruvate dehydrogenase E1 α chain encoded by the gene MG_274. In addition, TIM207 was noticed to be less cytotoxic to HeLa cells and this correlated with the production of less hydrogen peroxide by this strain. This strain was also less efficient in inducing the differentiation of THP-1 cell line as compared to wild type M. genitalium. CONCLUSIONS The results of the study suggest that MG207 is an important signaling protein of M. genitalium and its presence may be crucial for the virulence of this species.
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Affiliation(s)
- Mario A Martinez
- Regional Academic Health Center and Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, Edinburg, TX 78541, USA
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Strain-specific regulatory role of eukaryote-like serine/threonine phosphatase in pneumococcal adherence. Infect Immun 2012; 80:1361-72. [PMID: 22311926 DOI: 10.1128/iai.06311-11] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pneumoniae exploits a battery of virulence factors to colonize the host. Although the eukaryote-like Ser/Thr kinase of S. pneumoniae (StkP) has been implicated in physiology and virulence, the role of its cotranscribing phosphatase (PhpP) has remained elusive. The construction of nonpolar markerless phpP knockout mutants (ΔphpP) in two pathogenic strains, D39 (type 2) and 6A-EF3114 (type 6A), indicated that PhpP is not indispensable for pneumococcal survival. Further, PhpP also participates in the regulation of cell wall biosynthesis/division, adherence, and biofilm formation in a strain-specific manner. Additionally, we provide hitherto-unknown in vitro and in vivo evidence of a physiologically relevant biochemical link between the StkP/PhpP-mediated cognate regulation and the two-component regulatory system TCS06 (RR06/HK06) that regulates the expression of the gene encoding an important pneumococcal surface adhesin, CbpA, which was found to be significantly upregulated in ΔphpP mutants. In particular, StkP (threonine)-phosphorylated RR06 bound to the cbpA promoter with high efficiency even in the absence of the HK06-responsive and catalytically active aspartate 51 residue. Together, our findings unravel the significant contributions of PhpP in pneumococcal physiology and adherence.
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39
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Agarwal S, Agarwal S, Jin H, Pancholi P, Pancholi V. Serine/threonine phosphatase (SP-STP), secreted from Streptococcus pyogenes, is a pro-apoptotic protein. J Biol Chem 2012; 287:9147-67. [PMID: 22262847 DOI: 10.1074/jbc.m111.316554] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
This investigation illustrates an important property of eukaryote-type serine/threonine phosphatase (SP-STP) of group A Streptococcus (GAS) in causing programmed cell death of human pharyngeal cells. The secretory nature of SP-STP, its elevated expression in the intracellular GAS, and the ability of wild-type GAS but not the GAS mutant devoid of SP-STP to cause apoptosis of the host cell both in vitro and in vivo suggest that GAS deploys SP-STP as an important virulence determinant to exploit host cell machinery for its own advantage during infection. The exogenously added SP-STP is able to enter the cytoplasm and subsequently traverses into the nucleus in a temporal fashion to cause apoptosis of the pharyngeal cells. The programmed cell death induced by SP-STP, which requires active transcription and de novo protein synthesis, is also caspase-dependent. Furthermore, the entry of SP-STP into the cytoplasm is dependent on its secondary structure as the catalytically inactive SP-STP with an altered structure is unable to internalize and cause apoptosis. The ectopically expressed wild-type SP-STP was found to be in the nucleus and conferred apoptosis of Detroit 562 pharyngeal cells. However, the catalytically inactive SP-STP was unable to cause apoptosis even when intracellularly expressed. The ability of SP-STP to activate pro-apoptotic signaling cascades both in the cytoplasm and in the nucleus resulted in mitochondrial dysfunctioning and perturbation in the phosphorylation status of histones in the nucleus. SP-STP thus not only functions as a virulence regulator but also as an important factor responsible for host-related pathogenesis.
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Affiliation(s)
- Shivani Agarwal
- Department of Pathology, Ohio State University College of Medicine, Columbus, Ohio 43210-1214, USA
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40
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Burnside K, Rajagopal L. Regulation of prokaryotic gene expression by eukaryotic-like enzymes. Curr Opin Microbiol 2012; 15:125-31. [PMID: 22221896 DOI: 10.1016/j.mib.2011.12.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 12/01/2011] [Accepted: 12/14/2011] [Indexed: 12/30/2022]
Abstract
A growing body of evidence indicates that serine/threonine kinases (STKs) and phosphatases (STPs) regulate gene expression in prokaryotic organisms. As prokaryotic STKs and STPs are not DNA binding proteins, regulation of gene expression is accomplished through post-translational modification of their targets. These include two-component response regulators, DNA binding proteins and proteins that mediate transcription and translation. This review summarizes our current understanding of how STKs and STPs mediate gene expression in prokaryotes. Further studies to identify environmental signals that trigger the signaling cascade and elucidation of mechanisms that regulate crosstalk between eukaryotic-like signaling enzymes, two-component systems, and components of the transcriptional and translational machinery will facilitate a greater understanding of prokaryotic gene regulation.
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Affiliation(s)
- Kellie Burnside
- Department of Pediatric Infectious Diseases, University of Washington and Seattle Children's Hospital Research Institute, Seattle, WA 98101-1304, United States
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41
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Patenge N, Fiedler T, Kreikemeyer B. Common regulators of virulence in streptococci. Curr Top Microbiol Immunol 2012; 368:111-53. [PMID: 23242855 DOI: 10.1007/82_2012_295] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Streptococcal species are a diverse group of bacteria which can be found in animals and humans. Their interactions with host organisms can vary from commensal to pathogenic. Many of the pathogenic species are causative agents of severe, invasive infections in their hosts, accounting for a high burden of morbidity and mortality, associated with high economic costs in industry and health care. Among them, Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus pneumoniae, and Streptococcus suis are discussed here. An environmentally stimulated and tightly controlled expression of their virulence factors is of utmost importance for their pathogenic potential. Thus, the most universal and widespread regulators from the classes of stand-alone transcriptional regulators, two-component signal transduction systems (TCS), eukaryotic-like serine/threonine kinases, and small noncoding RNAs are the topic of this chapter. The regulatory levels are reviewed with respect to function, activity, and their role in pathogenesis. Understanding of and interfering with transcriptional regulation mechanisms and networks is a promising basis for the development of novel anti-infective therapies.
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Affiliation(s)
- Nadja Patenge
- Institute of Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Schillingallee 70, 18057 Rostock, Germany
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42
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Burnside K, Lembo A, Harrell MI, Gurney M, Xue L, BinhTran NT, Connelly JE, Jewell KA, Schmidt BZ, de Los Reyes M, Tao WA, Doran KS, Rajagopal L. Serine/threonine phosphatase Stp1 mediates post-transcriptional regulation of hemolysin, autolysis, and virulence of group B Streptococcus. J Biol Chem 2011; 286:44197-44210. [PMID: 22081606 DOI: 10.1074/jbc.m111.313486] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Elucidating how serine/threonine phosphatases regulate kinase function and bacterial virulence is critical for our ability to combat these infections. Group B streptococci (GBS) are β-hemolytic Gram-positive bacteria that cause invasive infections in humans. To adapt to environmental changes, GBS encodes signaling mechanisms comprising two component systems and eukaryotic-like enzymes. We have previously described the importance of the serine/threonine kinase Stk1 to GBS pathogenesis. However, how the presence or absence of the cognate serine/threonine phosphatase Stp1 affects Stk1 function and GBS virulence is not known. Here, we show that GBS deficient only in Stp1 expression are markedly reduced for their ability to cause systemic infections, exhibit decreased β-hemolysin/cytolysin activity, and show increased sensitivity to autolysis. Although transcription of genes important for β-hemolysin/cytolysin expression and export is similar to the wild type (WT), 294 genes (excluding stp1) showed altered expression in the stp1 mutant and included autolysin genes. Furthermore, phosphopeptide enrichment analysis identified that 35 serine/threonine phosphopeptides, corresponding to 27 proteins, were unique to the stp1 mutant. This included phosphorylation of ATP synthase, DNA and RNA helicases, and proteins important for cell division and protein synthesis. Collectively, our results indicate that Stp1 is important for appropriate regulation of Stk1 function, hemolysin activity, autolysis, and GBS virulence.
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Affiliation(s)
- Kellie Burnside
- Department of Pediatric Infectious Diseases, University of Washington School of Medicine and Seattle Children's Hospital Research Institute, Seattle, Washington 98101
| | - Annalisa Lembo
- Department of Pediatric Infectious Diseases, University of Washington School of Medicine and Seattle Children's Hospital Research Institute, Seattle, Washington 98101
| | - Maria Isabel Harrell
- Department of Pediatric Infectious Diseases, University of Washington School of Medicine and Seattle Children's Hospital Research Institute, Seattle, Washington 98101
| | - Michael Gurney
- Department of Biology and Center for Microbial Sciences, San Diego State University, San Diego, California 92182
| | - Liang Xue
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907
| | - Nguyen-Thao BinhTran
- Department of Pediatric Infectious Diseases, University of Washington School of Medicine and Seattle Children's Hospital Research Institute, Seattle, Washington 98101
| | - James E Connelly
- Department of Pediatric Infectious Diseases, University of Washington School of Medicine and Seattle Children's Hospital Research Institute, Seattle, Washington 98101
| | - Kelsea A Jewell
- Department of Pediatric Infectious Diseases, University of Washington School of Medicine and Seattle Children's Hospital Research Institute, Seattle, Washington 98101
| | - Byron Z Schmidt
- Department of Pediatric Infectious Diseases, University of Washington School of Medicine and Seattle Children's Hospital Research Institute, Seattle, Washington 98101
| | - Melissa de Los Reyes
- Department of Pediatric Infectious Diseases, University of Washington School of Medicine and Seattle Children's Hospital Research Institute, Seattle, Washington 98101
| | - Weiguo Andy Tao
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907
| | - Kelly S Doran
- Department of Biology and Center for Microbial Sciences, San Diego State University, San Diego, California 92182
| | - Lakshmi Rajagopal
- Department of Pediatric Infectious Diseases, University of Washington School of Medicine and Seattle Children's Hospital Research Institute, Seattle, Washington 98101.
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