THE SBMA LOCUS IS INVOLVED IN VIRULENCE-ASSOSIATED PHENOTYPES

CORBALÁN NATALIA SOLEDAD; POMARES MARÍA FERNANDA; LAMI, MARÍA JESUS; DE CRISTÓBAL RICARDO EZEQUIEL; DELGADO MONICA; VINCENT P.A

San Luis.Potrero de Los Funes

Congreso; SAIB; 2011

SAIB

THE sbmA LOCUS IS INVOLVED IN PHENOTYPES ASSOSIATED TO VIRULENCE Corbalan NS, Pomares MF, De Cristobal RE, Adler C, Delgado MA, Vincent PA Inst. Superior de Investigaciones Biológicas INSIBIO (UNT-CONICET).E-mail: ncorbalan@fbqf.unt.edu.ar SbmA protein is involved in the transport of MccB17, MccJ25, bleomycin and proline rich peptides into the E. coli cytoplasm. In Brucella abortus, Sinorhizobium meliloti and Mycobacterium tuberculosis the SbmA homologue, BacA, is essential for the chronic infection of these pathogens. For this reason we evaluated SbmA role in Salmonella enterica serovar Typhimurium ability to infect and replicate within macrophages. The sbmA mutant strain showed increased intracellular replication compared to parental strain. Further assays demonstrated that this phenomenon was caused by increased resistance to the acidic pH present in the macrophage environment. Biofilm formation and swarming are two important bacterial traits that enhance pathogen chances of survival in competitive environments and the ability to infect hosts. Assays demonstrated that sbmA absence significantly enhanced biofilm and swarming phenotypes. Additionally, mutation in yaiW, gene that belonging to the same operon as sbmA does, affected biofilm and swarming in the same way as sbmA mutation. Finally, a gene profile expression assay (nanostring) of sbmA and yaiW mutans compared to wild type showed that the transcription levels of genes implicated in swarming and motility were enhanced in those mutants. Taken together these results suggest that sbmA is involved in important physiological roles related to virulence.