title: Serine/threonine protein kinase PrkA of the human pathogen Listeria monocytogenes: biochemical characterization and identification of interacting partners through proteomic approaches.
abstract: Listeria monocytogenes is the causative agent of listeriosis, a very serious food-borne human disease. The analysis of the proteins coded by the L. monocytogenes genome reveals the presence of two eukaryotic-type Ser/Thr-kinases (lmo1820 and lmo0618) and a Ser/Thr-phosphatase (lmo1821). Protein phosphorylation regulates enzyme activities and protein interactions participating in physiological and pathophysiological processes in bacterial diseases. However in the case of L. monocytogenes there is scarce information about biochemical properties of these enzymes, as well as the physiological processes that they modulate. In the present work the catalytic domain of the protein coded by lmo1820 was produced as a functional His(6)-tagged Ser/Thr-kinase, and was denominated PrkA. PrkA was able to autophosphorylate specific Thr residues within its activation loop sequence. A similar autophosphorylation pattern was previously reported for Ser/Thr-kinases from related prokaryotes, whose role in kinase activity and substrate recruitment was demonstrated. We studied the kinase interactome using affinity chromatography and proteomic approaches. We identified 62 proteins that interact, either directly or indirectly, with the catalytic domain of PrkA, including proteins that participate in carbohydrates metabolism, cell wall metabolism and protein synthesis. Our results suggest that PrkA could be involved in the regulation of a variety of fundamental biological processes.
authors.affiliation: Institut Pasteur de Montevideo/Instituto de Investigaciones Biológicas Clemente Estable, Unidad de Bioquímica y Proteómica Analíticas, Uruguay.
authors.forename: Analía
authors.initials: A
authors.lastname: Lima
authors.forename: Rosario
authors.initials: R
authors.lastname: Durán
authors.forename: Gustavo Enrique
authors.initials: GE
authors.lastname: Schujman
authors.forename: María Julia
authors.initials: MJ
authors.lastname: Marchissio
authors.forename: María Magdalena
authors.initials: MM
authors.lastname: Portela
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Obal
authors.forename: Otto
authors.initials: O
authors.lastname: Pritsch
authors.forename: Diego
authors.initials: D
authors.lastname: de Mendoza
authors.forename: Carlos
authors.initials: C
authors.lastname: Cerveñansky
mesh_terms: D001426:Bacterial Proteins; D020134:Catalytic Domain; D006801:Humans; D008089:Listeria monocytogenes / Q000201:enzymology*; D008660:Metabolism; D010766:Phosphorylation; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D040901:Proteomics / Q000379:methods; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D017346:Protein Serine-Threonine Kinases