Interaction of LipidII with specific residues of its extracytoplasmic domain governs appropriate localization and optimal activation of Mycobacterium tuberculosis PknB

ABSTRACT: The Mycobacterium tuberculosis kinase PknB is essential for growth and survival of the pathogen in vitro and in vivo. Here we present the results of our efforts to elucidate the mechanism of regulation of PknB activity. The specific residues in the kinases’s extracytoplasmic domain that are essential for ligand interaction and survival of the bacterium have been identified. The extracytoplasmic domain interacts with mDAP-containing LipidII, and this is abolished upon mutation of the ligand-interacting residues. Abrogation of ligand-binding or sequestration of the ligand leads to aberrant localization of PknB. Contrary to the prevailing hypothesis, abrogation of ligand-binding is linked to activation loop hyperphosphorylation, and indiscriminate hyperphosphorylation of PknB substrates as well as other proteins, ultimately causing loss of homeostasis and cell death. We propose that the ligand-kinase interaction directs the appropriate localization of the kinase, coupled to stringently controlled activation of PknB., and consequently the downstream processes thereof.

INSTRUMENT(S):

ORGANISM(S): Mycobacterium Tuberculosis H37rv

DISEASE(S): Tuberculosis

SUBMITTER: Bolaji F Oyeyemi  

LAB HEAD: Vinay K. Nandicoori

PROVIDER: PXD012180 | Pride | 2019-03-14

REPOSITORIES: Pride