Characterization of the Biological Effect Mediated by Mycobacterial Kinase PknG on Protein Phosphorylation and Acetylation.

Tuberculosis (TB) remains a significant global public health challenge, with post-translational modifications (PTMs) in mycobacteria being integral to physiological processes, pathogenesis, and drug resistance mechanisms. Protein kinase G (PknG), the only reported secreted kinase in mycobacteria, is associated with virulence, immune evasion, and drug resistance. Nevertheless, the comprehensive range of proteins and phosphorylation modifications regulated by PknG in mycobacteria has not yet been fully elucidated. This study conducted a systematic investigation into the dynamic alterations in the proteome and phosphoproteome of mycobacteria following the overexpression of PknG. A comprehensive analysis identified 3836 proteins and 467 phosphorylation sites, revealing the regulatory role of PknG in energy metabolism pathways and binding processes. Additionally, the study highlighted the interplay between protein phosphorylation and lysine acetylation, noting a reduction in lysine acetylation that is linked to carbon metabolism and various energy-related pathways in the PknG overexpression strains. The role of PknG in growth, infection, and the secretion of the inflammatory factor was further investigated, providing new insights into phosphorylation functions within mycobacteria and potential clinical targets for tuberculosis treatment. The study additionally provides an innovative perspective on the interplay between post-translational modifications in mycobacteria.