title: Flagellin FliC Phosphorylation Affects Type 2 Protease Secretion and Biofilm Dispersal in Pseudomonas aeruginosa PAO1.
abstract: Protein phosphorylation has a major role in controlling the life-cycle and infection stages of bacteria. Proteome-wide occurrence of S/T/Y phosphorylation has been reported for many prokaryotic systems. Previously, we reported the phosphoproteome of Pseudomonas aeruginosa and Pseudomonas putida. In this study, we show the role of S/T phosphorylation of one motility protein, FliC, in regulating multiple surface-associated phenomena of P. aeruginosa PAO1. This is the first report of occurrence of phosphorylation in the flagellar protein, flagellin FliC in its highly conserved N-terminal NDO domain across several Gram negative bacteria. This phosphorylation is likely a well-regulated phenomenon as it is growth phase dependent in planktonic cells. The absence of phosphorylation in the conserved T27 and S28 residues of FliC, interestingly, did not affect swimming motility, but affected the secretome of type 2 secretion system (T2SS) and biofilm formation of PAO1. FliC phosphomutants had increased levels and activities of type 2 secretome proteins. The secretion efficiency of T2SS machinery is associated with flagellin phosphorylation. FliC phosphomutants also formed reduced biofilms at 24 h under static conditions and had delayed biofilm dispersal under dynamic flow conditions, respectively. The levels of type 2 secretome and biofilm formation under static conditions had an inverse correlation. Hence, increase in type 2 secretome levels was accompanied by reduced biofilm formation in the FliC phosphomutants. As T2SS is involved in nutrient acquisition and biofilm dispersal during survival and spread of P. aeruginosa, we propose that FliC phosphorylation has a role in ecological adaptation of this opportunistic environmental pathogen. Altogether, we found a system of phosphorylation that affects key surface related processes such as proteases secretion by T2SS, biofilm formation and dispersal.
authors.affiliation: Metabolites Biology Lab, Department of Biological Sciences, National University of Singapore, Singapore, Singapore.|Microbiology Lab, Faculty of Dentistry, National University of Singapore, Singapore, Sinagpore.
authors.forename: Tanujaa
authors.initials: T
authors.lastname: Suriyanarayanan
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore, Singapore.|Rajalakshmi Engineering College, Chennai, Tamil Nadu, India.
authors.forename: Saravanan
authors.initials: S
authors.lastname: Periasamy
authors.affiliation: Department of Molecular and Cellular Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan.
authors.forename: Miao-Hsia
authors.initials: MH
authors.lastname: Lin
authors.affiliation: Department of Molecular and Cellular Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ishihama
authors.affiliation: Metabolites Biology Lab, Department of Biological Sciences, National University of Singapore, Singapore, Singapore.|NUS Environmental Research Institute (NERI), National University of Singapore, Singapore, Singapore.|Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore, Singapore.|Synthetic Biology for Clinical and Technological Innovation (SynCTI), Centre for Life Sciences, National University of Singapore, Singapore, Singapore.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Swarup
mesh_terms: D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018441:Biofilms; D005408:Flagellin / Q000235:genetics* / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D009154:Mutation; D010447:Peptide Hydrolases / Q000378:metabolism*; D010766:Phosphorylation; D040901:Proteomics / Q000379:methods; D011550:Pseudomonas aeruginosa / Q000378:metabolism / Q000502:physiology*; D012694:Serine / Q000378:metabolism; D013912:Threonine / Q000378:metabolism; D000069178:Type II Secretion Systems / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D000069178:Type II Secretion Systems; D005408:Flagellin; D013912:Threonine; D012694:Serine; D010447:Peptide Hydrolases