Characterization of Serine/Threonine protein kinases K (PknK) in Mycobacterium

Abstract:

[Objective] Serine/Threonine Protein Kinases K (PknK) is a eukaryotic-like Ser/Thr protein kinase in Mycobacterium, with important roles in cell growth and signaling transduction. However, its underlying mechanism of action is not completed. [Methods] The pknK knockout strain △pknK was obtained by phage specialized transduction meanwhile the complement strain pMV361-pknK/ΔpknK and the overexpressing strain with pMV261-pknK/BCG was construed for further analysis. The growth curve and resistance of the obtained strains were determined. PknK-interacting proteins were identified by pulldown-MS. [Results] PknK affected Mycobacterium growth, and △pknK had growth advantage over BCG and pMV261-pknK/BCG. Knockout pknK led to increased multiple antibiotic susceptibility. We identified the binding proteins for PnK in BCG using in pulldown combined with Mass Spectrometry. [Conclusion] PknK negatively regulates BCG growth and increases antibiotic susceptibility in mycobacteria. The PknK binding proteins include a Ser/Thr protein kinase PknA, and two component system regulators such as MtrA, MoxR1 and TrcR, which is expected to be a resource for understanding the PknK-mediated signaling pathways in Mycobacterium, thus facilitating new therapeutic strategies for antibiotic-resistant infections.