Journal Article

Characterization of a bacterial tyrosine kinase in Porphyromonas gingivalis involved in polymicrobial synergy

Liu, Chengcheng, Whitmore, Sarah E., Wright, Christopher J., Xue, Peng, Hirano, Takanori, Hackett, Murray, Lamont, Richard J.

2014

Overview

Interspecies communication between Porphyromonas gingivalis and Streptococcus gordonii underlies the development of synergistic dual species communities. Contact with S. gordonii initiates signal transduction within P. gingivalis that is based on protein tyrosine (de)phosphorylation. In this study, we characterize a bacterial tyrosine (BY) kinase (designated Ptk1) of P. gingivalis and demonstrate its involvement in interspecies signaling. Ptk1 can utilize ATP for autophosphorylation and is dephosphorylated by the P. gingivalis tyrosine phosphatase, Ltp1. Community development with S. gordonii is severely abrogated in a ptk1 mutant of P. gingivalis, indicating that tyrosine kinase activity is required for maximal polymicrobial synergy. Ptk1 controls the levels of the transcriptional regulator CdhR and the fimbrial adhesin Mfa1 which mediates binding to S. gordonii. The ptk1 gene is in an operon with two genes involved in exopolysaccharide synthesis, and similar to other BY kinases, Ptk1 is necessary for exopolysaccharide production in P. gingivalis. Ptk1 can phosphorylate the capsule related proteins PGN_0224, a UDP‐acetyl‐mannosamine dehydrogenase, and PGN_0613, a UDP‐glucose dehydrogenase, in P. gingivalis. Knockout of ptk1 in an encapsulated strain of P. gingivalis resulted in loss of capsule production. Collectively these results demonstrate that the P. gingivalis Ptk1 BY kinase regulates interspecies communication and controls heterotypic community development with S. gordonii through adjusting the levels of the Mfa1 adhesin and exopolysaccharide. A novel role for a bacterial tyrosine kinase is identified. In the periodontal pathogen Porphyromonas gingivalis, a tyrosine kinase controls polymicrobial synergy with Streptococcus gordonii through regulation of adhesin and extracellular polysaccharide expression.

• Publisher: John Wiley & Sons, Inc,Blackwell Publishing Ltd
• Subject: Adenosine Triphosphate - metabolism / Bacteria / Bacterial Adhesion / Bacterial Capsules - metabolism / Cloning / Community / Community development / Dehydrogenase / E coli / Enzymes / Exopolysaccharides / Gene Deletion / Glucose dehydrogenase / Gum disease / Kinases / Microbial Interactions / Original Research / periodontitis / Phosphatase / Phosphorylation / polymicrobial synergy / Porphyromonas gingivalis / Porphyromonas gingivalis - enzymology / Porphyromonas gingivalis - genetics / Porphyromonas gingivalis - growth & development / Protein Processing, Post-Translational / Protein-tyrosine kinase / Protein-Tyrosine Kinases - genetics / Protein-Tyrosine Kinases - metabolism / Protein-tyrosine-phosphatase / Proteins / Signal Transduction / Streptococcus gordonii / Streptococcus gordonii - growth & development / Transcription / Tyrosine / tyrosine kinase