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Aberuagba A, Joel EB, Bello AJ, Igunnu A, Malomo SO, Olorunniji FJ. Thermophilic PHP Protein Tyrosine Phosphatases (Cap8C and Wzb) from Mesophilic Bacteria. Int J Mol Sci 2024; 25:1262. [PMID: 38279261 PMCID: PMC10816263 DOI: 10.3390/ijms25021262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Revised: 01/14/2024] [Accepted: 01/17/2024] [Indexed: 01/28/2024] Open
Abstract
Protein tyrosine phosphatases (PTPs) of the polymerase and histidinol phosphatase (PHP) superfamily with characteristic phosphatase activity dependent on divalent metal ions are found in many Gram-positive bacteria. Although members of this family are co-purified with metal ions, they still require the exogenous supply of metal ions for full activation. However, the specific roles these metal ions play during catalysis are yet to be well understood. Here, we report the metal ion requirement for phosphatase activities of S. aureus Cap8C and L. rhamnosus Wzb. AlphaFold-predicted structures of the two PTPs suggest that they are members of the PHP family. Like other PHP phosphatases, the two enzymes have a catalytic preference for Mn2+, Co2+ and Ni2+ ions. Cap8C and Wzb show an unusual thermophilic property with optimum activities over 75 °C. Consistent with this model, the activity-temperature profiles of the two enzymes are dependent on the divalent metal ion activating the enzyme.
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Affiliation(s)
- Adepeju Aberuagba
- School of Pharmacy & Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK; (A.A.); (E.B.J.); (A.J.B.)
| | - Enoch B. Joel
- School of Pharmacy & Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK; (A.A.); (E.B.J.); (A.J.B.)
- Department of Biochemistry, Faculty of Basic Medical Sciences, University of Jos, Jos 930003, Nigeria
| | - Adebayo J. Bello
- School of Pharmacy & Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK; (A.A.); (E.B.J.); (A.J.B.)
| | - Adedoyin Igunnu
- Department of Biochemistry, Faculty of Life Sciences, University of Ilorin, Ilorin 234031, Nigeria; (A.I.); (S.O.M.)
| | - Sylvia O. Malomo
- Department of Biochemistry, Faculty of Life Sciences, University of Ilorin, Ilorin 234031, Nigeria; (A.I.); (S.O.M.)
| | - Femi J. Olorunniji
- School of Pharmacy & Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK; (A.A.); (E.B.J.); (A.J.B.)
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Cellular Mn/Zn Ratio Influences Phosphoglucomutase Activity and Capsule Production in Streptococcus pneumoniae D39. J Bacteriol 2021; 203:e0060220. [PMID: 33875543 PMCID: PMC8316032 DOI: 10.1128/jb.00602-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Capsular polysaccharide (CPS) is a major virulence determinant for many human-pathogenic bacteria. Although the essential functional roles for CPS in bacterial virulence have been established, knowledge of how CPS production is regulated remains limited. Streptococcus pneumoniae (pneumococcus) CPS expression levels and overall thickness change in response to available oxygen and carbohydrate. These nutrients in addition to transition metal ions can vary significantly between host environmental niches and infection stage. Since the pneumococcus must modulate CPS expression among various host niches during disease progression, we examined the impact of the nutritional transition metal availability of manganese (Mn) and zinc (Zn) on CPS production. We demonstrate that increased Mn/Zn ratios increase CPS production via Mn-dependent activation of the phosphoglucomutase Pgm, an enzyme that functions at the branch point between glycolysis and the CPS biosynthetic pathway in a transcription-independent manner. Furthermore, we find that the downstream CPS protein CpsB, an Mn-dependent phosphatase, does not promote aberrant dephosphorylation of its target capsule-tyrosine kinase CpsD during Mn stress. Together, these data reveal a direct role for cellular Mn/Zn ratios in the regulation of CPS biosynthesis via the direct activation of Pgm. We propose a multilayer mechanism used by the pneumococcus in regulating CPS levels across various host niches. IMPORTANCE Evolving evidence strongly indicates that maintenance of metal homeostasis is essential for establishing colonization and continued growth of bacterial pathogens in the vertebrate host. In this study, we demonstrate the impact of cellular manganese/zinc (Mn/Zn) ratios on bacterial capsular polysaccharide (CPS) production, an important virulence determinant of many human-pathogenic bacteria, including Streptococcus pneumoniae. We show that higher Mn/Zn ratios increase CPS production via the Mn-dependent activation of the phosphoglucomutase Pgm, an enzyme that functions at the branch point between glycolysis and the CPS biosynthetic pathway. The findings provide a direct role for Mn/Zn homeostasis in the regulation of CPS expression levels and further support the ability of metal cations to act as important cellular signaling mediators in bacteria.
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Jung YJ, Miller DP, Perpich JD, Fitzsimonds ZR, Shen D, Ohshima J, Lamont RJ. Porphyromonas gingivalis Tyrosine Phosphatase Php1 Promotes Community Development and Pathogenicity. mBio 2019; 10:e02004-19. [PMID: 31551334 PMCID: PMC6759763 DOI: 10.1128/mbio.02004-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 08/23/2019] [Indexed: 01/17/2023] Open
Abstract
Protein-tyrosine phosphorylation in bacteria plays a significant role in multiple cellular functions, including those related to community development and virulence. Metal-dependent protein tyrosine phosphatases that belong to the polymerase and histindinol phosphatase (PHP) family are widespread in Gram-positive bacteria. Here, we show that Porphyromonas gingivalis, a Gram-negative periodontal pathogen, expresses a PHP protein, Php1, with divalent metal ion-dependent tyrosine phosphatase activity. Php1 tyrosine phosphatase activity was attenuated by mutation of conserved histidine residues that are important for the coordination of metal ions and by mutation of a conserved arginine residue, a key residue for catalysis in other bacterial PHPs. The php1 gene is located immediately downstream of the gene encoding the bacterial tyrosine (BY) kinase Ptk1, which was a substrate for Php1 in vitro Php1 rapidly caused the conversion of Ptk1 to a state of low tyrosine phosphorylation in the absence of discernible intermediate phosphoforms. Active Php1 was required for P. gingivalis exopolysaccharide production and for community development with the antecedent oral biofilm constituent Streptococcus gordonii under nutrient-depleted conditions. In contrast, the absence of Php1 had no effect on the ability of P. gingivalis to form monospecies biofilms. In vitro, Php1 enzymatic activity was resistant to the effects of the streptococcal secreted metabolites pABA and H2O2, which inhibited Ltp1, an enzyme in the low-molecular-weight (LMW) phosphotyrosine phosphatase family. Ptk1 reciprocally phosphorylated Php1 on tyrosine residues 159 and 161, which independently impacted phosphatase activity. Loss of Php1 rendered P. gingivalis nonvirulent in an animal model of periodontal disease. Collectively, these results demonstrate that P. gingivalis possesses active PHP and LMW tyrosine phosphatases, a unique configuration in Gram-negatives which may allow P. gingivalis to maintain phosphorylation/dephosphorylation homeostasis in multispecies communities. Moreover, Php1 contributes to the pathogenic potential of the organism.IMPORTANCE Periodontal diseases are among the most common infections of humans and are also associated with systemic inflammatory conditions. Colonization and pathogenicity of P. gingivalis are regulated by signal transduction pathways based on protein tyrosine phosphorylation and dephosphorylation. Here, we identify and characterize a novel component of the tyrosine (de)phosphorylation axis: a polymerase and histindinol phosphatase (PHP) family enzyme. This tyrosine phosphatase, designated Php1, was required for P. gingivalis community development with other oral bacteria, and in the absence of Php1 activity P. gingivalis was unable to cause disease in a mouse model of periodontitis. This work provides significant insights into the protein tyrosine (de)phosphorylation network in P. gingivalis, its adaptation to heterotypic communities, and its contribution to colonization and virulence.
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Affiliation(s)
- Young-Jung Jung
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - Daniel P Miller
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - John D Perpich
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - Zackary R Fitzsimonds
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - Daonan Shen
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - Jun Ohshima
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - Richard J Lamont
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
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Tahoun A, Masutani H, El-Sharkawy H, Gillespie T, Honda RP, Kuwata K, Inagaki M, Yabe T, Nomura I, Suzuki T. Capsular polysaccharide inhibits adhesion of Bifidobacterium longum 105-A to enterocyte-like Caco-2 cells and phagocytosis by macrophages. Gut Pathog 2017; 9:27. [PMID: 28469711 PMCID: PMC5412050 DOI: 10.1186/s13099-017-0177-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Accepted: 04/21/2017] [Indexed: 02/07/2023] Open
Abstract
Background Bifidobacterium longum 105-A produces markedly high amounts of capsular polysaccharides (CPS) and exopolysaccharides (EPS) that should play distinct roles in bacterial–host interactions. To identify the biological function of B. longum 105-A CPS/EPS, we carried out an informatics survey of the genome and identified the EPS-encoding genetic locus of B. longum 105-A that is responsible for the production of CPS/EPS. The role of CPS/EPS in the adaptation to gut tract environment and bacteria-gut cell interactions was investigated using the ΔcpsD mutant. Results A putative B. longum 105-A CPS/EPS gene cluster was shown to consist of 24 putative genes encoding a priming glycosyltransferase (cpsD), 7 glycosyltransferases, 4 CPS/EPS synthesis machinery proteins, and 3 dTDP-L-rhamnose synthesis enzymes. These enzymes should form a complex system that is involved in the biogenesis of CPS and/or EPS. To confirm this, we constructed a knockout mutant (ΔcpsD) by a double cross-over homologous recombination. Compared to wild-type, the ∆cpsD mutant showed a similar growth rate. However, it showed quicker sedimentation and formation of cell clusters in liquid culture. EPS was secreted by the ∆cpsD mutant, but had altered monosaccharide composition and molecular weight. Comparison of the morphology of B. longum 105-A wild-type and ∆cpsD by negative staining in light and electron microscopy revealed that the formation of fimbriae is drastically enhanced in the ∆cpsD mutant while the B. longum 105-A wild-type was coated by a thick capsule. The fimbriae expression in the ∆cpsD was closely associated with the disappearance of the CPS layer. The wild-type showed low pH tolerance, adaptation, and bile salt tolerance, but the ∆cpsD mutant had lost this survivability in gastric and duodenal environments. The ∆cpsD mutant was extensively able to bind to the human colon carcinoma Caco-2 cell line and was phagocytosed by murine macrophage RAW 264.7, whereas the wild-type did not bind to epithelial cells and totally resisted internalization by macrophages. Conclusions Our results suggest that CPS/EPS production and fimbriae formation are negatively correlated and play key roles in the survival, attachment, and colonization of B. longum 105-A in the gut. Electronic supplementary material The online version of this article (doi:10.1186/s13099-017-0177-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Amin Tahoun
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan.,Faculty of Veterinary Medicine, Kafr El-Sheikh University, Kafr El-Sheikh, 33516 Egypt
| | - Hisayoshi Masutani
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan
| | - Hanem El-Sharkawy
- Faculty of Veterinary Medicine, Kafr El-Sheikh University, Kafr El-Sheikh, 33516 Egypt.,Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan
| | - Trudi Gillespie
- CALM_live Imaging Facility, Centre for Inflammation Research, University of Edinburgh, Edinburgh, 47 EH16 4TJ UK
| | - Ryo P Honda
- Department of Molecular Pathobiochemistry, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan
| | - Kazuo Kuwata
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan.,Department of Gene and Development, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan.,Center for Highly Advanced Integration of Nano and Life Sciences, Gifu University (G-CHAIN), Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan
| | - Mizuho Inagaki
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan.,United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan
| | - Tomio Yabe
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan.,Center for Highly Advanced Integration of Nano and Life Sciences, Gifu University (G-CHAIN), Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan.,United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan
| | - Izumi Nomura
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan
| | - Tohru Suzuki
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan.,United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, Gifu, 501-1193 Japan
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5
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Kang HJ, Gilbert C, Badeaux F, Atlan D, LaPointe G. A tyrosine phosphorylation switch controls the interaction between the transmembrane modulator protein Wzd and the tyrosine kinase Wze of Lactobacillus rhamnosus. BMC Microbiol 2015; 15:40. [PMID: 25885688 PMCID: PMC4340800 DOI: 10.1186/s12866-015-0371-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 02/04/2015] [Indexed: 04/27/2023] Open
Abstract
Background One proposed mechanism for assembly of secreted heteropolysaccharides by many Gram positive bacteria relies on the coordinated action of a polymerization complex through reversible phosphorylation events. The role of the tyrosine protein kinase transmembrane modulator is, however, not well understood. Results The protein sequences deduced from the wzb, wzd and wze genes from Lactobacillus rhamnosus ATCC 9595 and RW-9595 M contain motifs also found in corresponding proteins CpsB, CpsC and CpsD from Streptococcus pneumoniae D39 (serotype 2). Use of an anti-phosphotyrosine antibody demonstrated that both Wzd and Wze can be found in tyrosine phosphorylated form. When tyrosine 266 was mutated to phenylalanine, WzdY266F showed slightly less phosphorylated protein than those produced by using eight other tyrosine mutated Wzd genes, when expressed along with Wze and Wzb in Lactococcus lactis subsp. cremoris MG1363. In order to demonstrate the importance of ATP for the interactions among these proteins, native and fusion Wzb, Wzd and Wze proteins were expressed and purified from Escherichia coli cultures. The modulator protein, Wzd, binds with the phosphotyrosine kinase Wze, irrespective of its phosphorylation status. However, Wze attained a higher phosphorylation level after interacting with phosphorylated Wzd in the presence of 10 mM ATP. This highly phosphorylated Wze did not remain in close association with phosphorylated Wzd. Conclusion The Wze tyrosine kinase protein of Lactobacillus rhamnosus thus carries out tyrosine phosphorylation of Wzd in addition to auto- and trans- phosphorylation of the kinase itself. Electronic supplementary material The online version of this article (doi:10.1186/s12866-015-0371-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hye-Ji Kang
- STELA Dairy Research Centre, INAF, Université Laval, Québec, G1V 0A6, QC, Canada. .,Present address: Academy of Immunology and Microbiology (AIM), Institute for Basic Science (IBS), Pohang, 790-784, Republic of Korea.
| | - Christophe Gilbert
- CIRI-U1111 INSERM- UMR5308 CNRS-UCBL-ENSL, Université de Lyon, Université Lyon 1, 10 rue Dubois, bât. Lwoff, F-69622, Villeurbanne cedex, France.
| | - Frédérique Badeaux
- STELA Dairy Research Centre, INAF, Université Laval, Québec, G1V 0A6, QC, Canada.
| | - Danièle Atlan
- CNRS, UMR5240, Unité microbiologie, adaptation et pathogénie, Villeurbanne, F-69622, France.
| | - Gisèle LaPointe
- STELA Dairy Research Centre, INAF, Université Laval, Québec, G1V 0A6, QC, Canada.
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Characterization and Expression Analysis of the Exopolysaccharide Gene Cluster inLactobacillus fermentumTDS030603. Biosci Biotechnol Biochem 2014; 73:2656-64. [DOI: 10.1271/bbb.90502] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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7
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Standish AJ, Morona R. The role of bacterial protein tyrosine phosphatases in the regulation of the biosynthesis of secreted polysaccharides. Antioxid Redox Signal 2014; 20:2274-89. [PMID: 24295407 PMCID: PMC3995119 DOI: 10.1089/ars.2013.5726] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
SIGNIFICANCE Tyrosine phosphorylation and associated protein tyrosine phosphatases are gaining prominence as critical mechanisms in the regulation of fundamental processes in a wide variety of bacteria. In particular, these phosphatases have been associated with the control of the biosynthesis of capsular polysaccharides and extracellular polysaccharides, critically important virulence factors for bacteria. RECENT ADVANCES Deletion and overexpression of the phosphatases result in altered polysaccharide biosynthesis in a range of bacteria. The recent structures of associated auto-phosphorylating tyrosine kinases have suggested that the phosphatases may be critical for the cycling of the kinases between monomers and higher order oligomers. CRITICAL ISSUES Additional substrates of the phosphatases apart from cognate kinases are currently being identified. These are likely to be critical to our understanding of the mechanism by which polysaccharide biosynthesis is regulated. FUTURE DIRECTIONS Ultimately, these protein tyrosine phosphatases are an attractive target for the development of novel antimicrobials. This is particularly the case for the polymerase and histidinol phosphatase family, which is predominantly found in bacteria. Furthermore, the determination of bacterial tyrosine phosphoproteomes will likely help to uncover the fundamental roles, mechanism, and critical importance of these phosphatases in a wide range of bacteria.
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Affiliation(s)
- Alistair J Standish
- School of Molecular and Biomedical Science, University of Adelaide , Adelaide, Australia
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8
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Streptococcus pneumoniae phosphotyrosine phosphatase CpsB and alterations in capsule production resulting from changes in oxygen availability. J Bacteriol 2014; 196:1992-2003. [PMID: 24659769 DOI: 10.1128/jb.01545-14] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Streptococcus pneumoniae produces a protective capsular polysaccharide whose production must be modulated for bacterial survival within various host niches. Capsule production is affected in part by a phosphoregulatory system comprised of CpsB, CpsC, and CpsD. Here, we found that growth of serotype 2 strain D39 under conditions of increased oxygen availability resulted in decreased capsule levels concurrent with an ∼5-fold increase in Cps2B-mediated phosphatase activity. The change in Cps2B phosphatase activity did not result from alterations in the levels of either the cps2B transcript or the Cps2B protein. Recombinant Cps2B expressed in Escherichia coli similarly exhibited increased phosphatase activity under conditions of high-oxygen growth. S. pneumoniae D39 derivatives with defined deletion or point mutations in cps2B demonstrated reduced phosphatase activity with corresponding increases in levels of Cps2D tyrosine phosphorylation. There was, however, no correlation between these phenotypes and the level of capsule production. During growth under reduced-oxygen conditions, the Cps2B protein was essential for parental levels of capsule, but phosphatase activity alone could be eliminated without an effect on capsule. Under increased-oxygen conditions, deletion of cps2B did not affect capsule levels. These results indicate that neither Cps2B phosphatase activity nor Cps2D phosphorylation levels per se are determinants of capsule levels, whereas the Cps2B protein is important for capsule production during growth under conditions of reduced but not enhanced oxygen availability. Roles for factors outside the capsule locus, possible interactions between capsule regulatory proteins, and links to other cellular processes are also suggested by the results described in this study.
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Cefalo AD, Broadbent JR, Welker DL. The Streptococcus thermophilus protein Wzh functions as a phosphotyrosine phosphatase. Can J Microbiol 2013; 59:391-8. [PMID: 23750953 DOI: 10.1139/cjm-2013-0094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Amino acid residues that are important for metal binding and catalysis in Gram-positive phosphotyrosine phosphatases were identified in the Wzh protein of Streptococcus thermophilus MR-1C by using sequence comparisons. A His-tagged fusion Wzh protein was purified from Escherichia coli cultures and tested for phosphatase activity against synthetic phosphotyrosine and phosphoserine-threonine peptides. Purified Wzh released 2316.5 ± 138.7 pmol PO4·min(-1)·μg(-1) from phosphotyrosine peptide-1 and 2345.7 ± 135.2 pmol PO4·min(-1)·μg(-1) from phosphotyrosine peptide-2. The presence of the phosphotyrosine phosphatase inhibitor sodium vanadate decreased purified Wzh activity by 45%-50% at 1 mmol·L(-1), 74%-84% at 5 mmol·L(-1), and by at least 88% at 10 mmol·L(-1). Purified Wzh had no detectable activity against the phosphoserine-threonine peptide. These results clearly establish that S. thermophilus MR-1C Wzh functions as a phosphotyrosine phosphatase that could function to remove phosphate groups from proteins involved in exopolysaccharide biosynthesis, including the protein tyrosine kinase Wze and priming glycosyltransferase.
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Affiliation(s)
- Angela D Cefalo
- Department of Biology, Utah State University, 5305 Old Main Hill, Logan, UT 84322, USA.
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10
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Standish AJ, Salim AA, Capon RJ, Morona R. Dual inhibition of DNA polymerase PolC and protein tyrosine phosphatase CpsB uncovers a novel antibiotic target. Biochem Biophys Res Commun 2012. [PMID: 23194664 DOI: 10.1016/j.bbrc.2012.11.049] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Increasing antibiotic resistance is making the identification of novel antimicrobial targets critical. Recently, we discovered an inhibitor of protein tyrosine phosphatase CpsB, fascioquinol E (FQE), which unexpectedly inhibited the growth of Gram-positive pathogens. CpsB is a member of the polymerase and histidinol phosphate phosphatase (PHP) domain family. Another member of this family found in a variety of Gram-positive pathogens is DNA polymerase PolC. We purified the PHP domain from PolC (PolC(PHP)), and showed that this competes away FQE inhibition of CpsB phosphatase activity. Furthermore, we showed that this domain hydrolyses the 5'-p-nitrophenyl ester of thymidine-5'-monophosphate (pNP-TMP), which has been used as a measure of exonuclease activity. Finally, we showed that FQE not only inhibits the phosphatase activity of CpsB, but also ability of PolC(PHP) to catalyse the hydrolysis of pNP-TMP. This suggests that PolC may be the essential target of FQE, and that the PHP domain may represent an as yet untapped target for the development of novel antibiotics.
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Affiliation(s)
- Alistair J Standish
- School of Molecular and Biomedical Science, University of Adelaide, Adelaide, SA 5005, Australia.
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11
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Mori Y, Maeda M, Takegawa K, Kimura Y. PhpA, a tyrosine phosphatase of Myxococcus xanthus, is involved in the production of exopolysaccharide. Microbiology (Reading) 2012; 158:2546-2555. [DOI: 10.1099/mic.0.059824-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Yumi Mori
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795, Japan
| | - Miri Maeda
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795, Japan
| | - Kaoru Takegawa
- Department of Bioscience and Biotechnology, Kyushu University, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
| | - Yoshio Kimura
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795, Japan
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12
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Standish AJ, Salim AA, Zhang H, Capon RJ, Morona R. Chemical inhibition of bacterial protein tyrosine phosphatase suppresses capsule production. PLoS One 2012; 7:e36312. [PMID: 22629313 PMCID: PMC3356977 DOI: 10.1371/journal.pone.0036312] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Accepted: 04/01/2012] [Indexed: 12/12/2022] Open
Abstract
Capsule polysaccharide is a major virulence factor for a wide range of bacterial pathogens, including Streptococcus pneumoniae. The biosynthesis of Wzy-dependent capsules in both gram-negative and -positive bacteria is regulated by a system involving a protein tyrosine phosphatase (PTP) and a protein tyrosine kinase. However, how the system functions is still controversial. In Streptococcus pneumoniae, a major human pathogen, the system is present in all but 2 of the 93 serotypes found to date. In order to study this regulation further, we performed a screen to find inhibitors of the phosphatase, CpsB. This led to the observation that a recently discovered marine sponge metabolite, fascioquinol E, inhibited CpsB phosphatase activity both in vitro and in vivo at concentrations that did not affect the growth of the bacteria. This inhibition resulted in decreased capsule synthesis in D39 and Type 1 S. pneumoniae. Furthermore, concentrations of Fascioquinol E that inhibited capsule also lead to increased attachment of pneumococci to a macrophage cell line, suggesting that this compound would inhibit the virulence of the pathogen. Interestingly, this compound also inhibited the phosphatase activity of the structurally unrelated gram-negative PTP, Wzb, which belongs to separate family of protein tyrosine phosphatases. Furthermore, incubation with Klebsiella pneumoniae, which contains a homologous phosphatase, resulted in decreased capsule synthesis. Taken together, these data provide evidence that PTPs are critical for Wzy-dependent capsule production across a spectrum of bacteria, and as such represents a valuable new molecular target for the development of anti-virulence antibacterials.
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Affiliation(s)
- Alistair J Standish
- School of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia, Australia.
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13
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Cefalo AD, Broadbent JR, Welker DL. Intraspecific and interspecific interactions among proteins regulating exopolysaccharide synthesis in Streptococcus thermophilus, Streptococcus iniae, and Lactococcus lactis subsp. cremoris and the assessment of potential lateral gene transfer. Can J Microbiol 2011; 57:1002-15. [PMID: 22107596 DOI: 10.1139/w11-090] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Using the yeast two-hybrid system, intraspecific protein interactions were detected in Streptococcus iniae and Lactococcus lactis subsp. cremoris between the transmembrane activation protein (CpsC and EpsA, respectively) and the protein tyrosine kinase (CpsD and EpsB, respectively), between two protein tyrosine kinases, and between the protein tyrosine kinase and the phosphotyrosine phosphatase (CpsB and EpsC, respectively). For each of these intraspecific interactions, interspecific interactions were also detected when one protein was from S. iniae and the other was from Streptococcus thermophilus . Interactions were also observed between two protein tyrosine kinases when one protein was from either of the Streptococcus species and the other from L. lactis subsp. cremoris. The results and sequence comparisons performed in this study support the conclusion that interactions among the components of the tyrosine kinase - phosphatase regulatory system are conserved in the order Lactobacillales and that interspecific genetic exchanges of the genes that encode these proteins have the potential to form functional recombinants. A better understanding of intraspecific and interspecific protein interactions involved in regulating exopolysaccharide biosynthesis may facilitate construction of improved strains for industrial uses as well as identification of factors needed to form functional regulatory complexes in naturally occurring recombinants.
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Affiliation(s)
- Angela D Cefalo
- Department of Biology, Utah State University, Logan, UT 84322, USA.
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14
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Huang H, Hagelueken G, Whitfield C, Naismith JH. Crystallization and preliminary crystallographic analysis of the bacterial capsule assembly-regulating tyrosine phosphatases Wzb of Escherichia coli and Cps4B of Streptococcus pneumoniae. Acta Crystallogr Sect F Struct Biol Cryst Commun 2009; 65:770-2. [PMID: 19652335 PMCID: PMC2720329 DOI: 10.1107/s1744309109023914] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 06/22/2009] [Indexed: 11/18/2022]
Abstract
Bacterial tyrosine kinases and their cognate phosphatases are key players in the regulation of capsule assembly and thus are important virulence determinants of these bacteria. Examples of the kinase/phosphatase pairing are found in Gram-negative bacteria such as Escherichia coli (Wzc and Wzb) and in Gram-positive bacteria such as Streptococcus pneumoniae (CpsCD and CpsB). Although Wzb and Cps4B are both predicted to dephosphorylate the C-terminal tyrosine cluster of their cognate tyrosine kinase, they appear on the basis of protein sequence to belong to quite different enzyme classes. Recombinant purified proteins Cps4B of S. pneumoniae TIGR4 and Wzb of E. coli K-30 have been crystallized. Wzb crystals belonged to space-group family P3(x)21 and diffracted to 2.7 A resolution. Crystal form I of Cps4B belonged to space-group family P4(x)2(1)2 and diffracted to 2.8 A resolution; crystal form II belonged to space group P2(1)2(1)2(1) and diffracted to 1.9 A resolution.
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Affiliation(s)
- Hexian Huang
- Centre for Biomolecular Sciences, The University of St Andrews, Fife KY16 9RH, Scotland
| | - Gregor Hagelueken
- Centre for Biomolecular Sciences, The University of St Andrews, Fife KY16 9RH, Scotland
| | - Chris Whitfield
- Department of Molecular and Cellular Biology, University of Guelph, Ontario N1G 2W1, Canada
| | - James H. Naismith
- Centre for Biomolecular Sciences, The University of St Andrews, Fife KY16 9RH, Scotland
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15
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Hagelueken G, Huang H, Mainprize IL, Whitfield C, Naismith JH. Crystal structures of Wzb of Escherichia coli and CpsB of Streptococcus pneumoniae, representatives of two families of tyrosine phosphatases that regulate capsule assembly. J Mol Biol 2009; 392:678-88. [PMID: 19616007 PMCID: PMC2777267 DOI: 10.1016/j.jmb.2009.07.026] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 07/07/2009] [Accepted: 07/09/2009] [Indexed: 12/11/2022]
Abstract
Many Gram-positive and Gram-negative bacteria utilize polysaccharide surface layers called capsules to evade the immune system; consequently, the synthesis and export of the capsule are a potential therapeutic target. In Escherichia coli K-30, the integral membrane tyrosine autokinase Wzc and the cognate phosphatase Wzb have been shown to be key for both synthesis and assembly of capsular polysaccharides. In the Gram-positive bacterium Streptococcus pneumoniae, the CpsCD complex is analogous to Wzc and the phosphatase CpsB is the corresponding cognate phosphatase. The phosphatases are known to dephosphorylate their corresponding autokinases, yet despite their functional equivalence, they share no sequence homology. We present the structure of Wzb in complex with phosphate and high-resolution structures of apo-CpsB and a phosphate-complexed CpsB. We show that both proteins are active toward Wzc and thereby demonstrate that CpsB is not specific for CpsCD. CpsB is a novel enzyme and represents the first solved structure of a tyrosine phosphatase from a Gram-positive bacterium. Wzb and CpsB have completely different structures, suggesting that they must operate by very different mechanisms. Although the mechanism of Wzb can be inferred from previous studies, CpsB appears to have a tyrosine phosphatase mechanism not observed before. We propose a chemical mechanism for CpsB based on site-directed mutagenesis and structural data.
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Affiliation(s)
- Gregor Hagelueken
- Centre for Biomolecular Sciences, The University of St. Andrews, Fife KY16 9RH, UK
| | - Hexian Huang
- Centre for Biomolecular Sciences, The University of St. Andrews, Fife KY16 9RH, UK
| | - Iain L. Mainprize
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Chris Whitfield
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - James H. Naismith
- Centre for Biomolecular Sciences, The University of St. Andrews, Fife KY16 9RH, UK
- Corresponding author.
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16
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Lebeer S, Verhoeven TLA, Francius G, Schoofs G, Lambrichts I, Dufrêne Y, Vanderleyden J, De Keersmaecker SCJ. Identification of a Gene Cluster for the Biosynthesis of a Long, Galactose-Rich Exopolysaccharide in Lactobacillus rhamnosus GG and Functional Analysis of the Priming Glycosyltransferase. Appl Environ Microbiol 2009; 75:3554-63. [PMID: 19346339 PMCID: PMC2687306 DOI: 10.1128/aem.02919-08] [Citation(s) in RCA: 201] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Accepted: 03/27/2009] [Indexed: 02/06/2023] Open
Abstract
Cell surface polysaccharides have an established role as virulence factors in human bacterial pathogens. Less documented are the biosynthesis and biological functions of surface polysaccharides in beneficial bacteria. We identified a gene cluster that encodes the enzymes and regulatory and transporter proteins for the different steps in the biosynthesis of extracellular polysaccharides (EPS) of the well-documented probiotic strain Lactobacillus rhamnosus GG. Subsequent mutation of the welE gene, encoding the priming glycosyltransferase within this cluster, and comparative phenotypic analyses of wild-type versus mutant strains confirmed the specific function of this gene cluster in the biosynthesis of high-molecular-weight, galactose-rich heteropolymeric EPS molecules. The phenotypic analyses included monomer composition determination, estimation of the polymer length of the isolated EPS molecules, and single-molecule force spectroscopy of the surface polysaccharides. Further characterization of the welE mutant also showed that deprivation of these long, galactose-rich EPS molecules results in an increased adherence and biofilm formation capacity of L. rhamnosus GG, possibly because of less shielding of adhesins such as fimbria-like structures.
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Affiliation(s)
- Sarah Lebeer
- Centre of Microbial and Plant Genetics, K.U. Leuven, Kasteelpark Arenberg, Belgium
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Revisiting histidine-dependent acid phosphatases: a distinct group of tyrosine phosphatases. Trends Biochem Sci 2009; 34:273-8. [PMID: 19467874 DOI: 10.1016/j.tibs.2009.03.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2008] [Revised: 03/05/2009] [Accepted: 03/06/2009] [Indexed: 11/22/2022]
Abstract
Although classical protein tyrosine phosphatase (PTP) superfamily members are cysteine-dependent, emerging evidence shows that many acid phosphatases (AcPs) function as histidine-dependent PTPs in vivo. These AcPs dephosphorylate phospho-tyrosine substrates intracellularly and could have roles in development and disease. In contrast to cysteine-dependent PTPs, they utilize histidine, rather than cysteine, for substrate dephosphorylation. Structural analyses reveal that active site histidine, but not cysteine, faces towards the substrate and functions as the phosphate acceptor. Nonetheless, during dephosphorylation, both histidine-dependent and cysteine-dependent PTPs use their active site arginine and aspartate for substrate binding and proton donation, respectively. Thus, we propose that they should be referred to as a distinct group of 'histidine-dependent PTPs' within the PTP superfamily.
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