Recognition of peptidoglycan and ?-lactam antibiotics by the extracellular domain of the Ser/Thr protein kinase StkP from Streptococcus pneumoniae.

ABSTRACT: The eukaryotic-type serine/threonine kinase StkP from Streptococcus pneumoniae is an important signal-transduction element that regulates the expression of numerous pneumococcal genes. We have expressed the extracellular C-terminal domain of StkP kinase (C-StkP), elaborated a three-dimensional structural model and performed a spectroscopical characterization of its structure and stability. Biophysical experiments show that C-StkP binds to synthetic samples of the cell wall peptidoglycan (PGN) and to ?-lactam antibiotics, which mimic the terminal portions of the PGN stem peptide. This is the first experimental report on the recognition of a minimal PGN unit by a PASTA-containing kinase, suggesting that non-crosslinked PGN may act as a signal for StkP function and pointing to this protein as an interesting target for ?-lactam antibiotics.

SUBMITTER: Maestro B 

PROVIDER: S-EPMC3035916 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature