title: A serine/threonine phosphatase encoded by MG_207 of Mycoplasma genitalium is critical for its virulence.
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.
authors: Regional Academic Health Center and Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, Edinburg, TX 78541, USA.
authors: Mario A
authors: MA
authors: Martinez
authors: Kishore
authors: K
authors: Das
authors: Sankaralingam
authors: S
authors: Saikolappan
authors: Luis A
authors: LA
authors: Materon
authors: Subramanian
authors: S
authors: Dhandayuthapani
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D016923:Cell Death; D002460:Cell Line; D004251:DNA Transposable Elements; D004847:Epithelial Cells / Q000382:microbiology; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D055786:Gene Knockout Techniques; D006801:Humans; D006868:Hydrolysis; D009000:Monocytes / Q000276:immunology; D016254:Mutagenesis, Insertional; D045704:Mycoplasma genitalium / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity*; D009596:Nitrophenols / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D037521:Virulence Factors / Q000235:genetics* / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D009596:Nitrophenols; D009943:Organophosphorus Compounds; D011994:Recombinant Proteins; D037521:Virulence Factors; C008644:nitrophenylphosphate; D010749:Phosphoprotein Phosphatases