Serine/threonine protein kinase PrkA of the human pathogen Listeria monocytogenes: Biochemical characterization and identification of interacting partners through proteomic approaches

ANALÍA LIMA; ROSARIO DURÁN; GUSTAVO ENRIQUE SCHUJMAN; MARÍA JULIA MARCHISSIO; MARÍA MAGDALENA PORTELA; GONZALO OBAL; OTTO PRITSCH; DIEGO DE MENDOZA; CARLOS CERVEÑANSKY

JOURNAL OF PROTEOMICS

ELSEVIER SCIENCE BV

Lugar: Londres; Año: 2011 vol. 74 p. 1720 - 1734

1874-3919

Listeria monocytogenes is the causative agent of listeriosis, a very serious food-borne humandisease. The analysis of the proteins coded by the L. monocytogenes genome reveals thepresence of two eukaryotic-type Ser/Thr-kinases (lmo1820 and lmo0618) and a Ser/Thrphosphatase(lmo1821). Protein phosphorylation regulates enzyme activities and proteininteractions participating in physiological and pathophysiological processes in bacterialdiseases. However in the case of L. monocytogenes there is scarce information aboutbiochemical properties of these enzymes, as well as the physiological processes that theymodulate. In the present work the catalytic domain of the protein coded by lmo1820 wasproduced as a functional His6-tagged Ser/Thr-kinase, and was denominated PrkA. PrkA wasable to autophosphorylate specific Thr residues within its activation loop sequence. Asimilar autophosphorylation pattern was previously reported for Ser/Thr-kinases fromrelated prokaryotes, whose role in kinase activity and substrate recruitment wasdemonstrated. We studied the kinase interactome using affinity chromatography andproteomic approaches. We identified 62 proteins that interact, either directly or indirectly,with the catalytic domain of PrkA, including proteins that participate in carbohydratesmetabolism, cell wall metabolism and protein synthesis. Our results suggest that PrkA couldbe involved in the regulation of a variety of fundamental biological processes.