THE sbmA LOCUS IS INVOLVED IN VIRULENCE ASSOSIATED PHENOTYPES

CORBALAN NATALIA; POMARES FERNANDA; LAMI, MARÍA JESUS; ADLER CONRADO; DE CRISTOBAL RE ; MONICA DELGADO; VINCENT, PAULA

San Luis

Congreso; SAIB; 2011

SbmA protein is involved in the transport of MccB17, MccJ25, bleomycin and proline rich peptides into the Escherichia coli cytoplasm. In Brucella abortus, Sinorhizobium meliloti and Mycobacterium tuberculosis the SbmA homologue,BacA, is essential for the chronic infection of these pathogens. We evaluated SbmA role in the Salmonella Typhimurium ability to infect and replicate within macrophages. The sbmA mutant strain showed increased intracellularreplication compared to parental strain. Further assays demonstr ated that this phenomenon was caused by increased resistance to the acidic pH present in the macrophage environment. Biofilm formation, aggregation and swarmingare important bacterial traits that affect pathogen chances of s urvival in competitive environments and the ability to infect ho sts. Assays demonstrated that sbmA absence significantly enhanced biofilm, aggregation and swarmingphenotypes. Additionally, mutation in yaiW, gene transcriptionally related to sbmA, affected biofilm and swarming in the same way as sbmA mutation did. However, the yaiW mutant showed a reduction in the aggregation phenotype. Agene profile expression assay of sbmA and yaiW mutans showed that the transcription levels of genes implicated in swa rming and motility were enhanced in those mutants. These results suggest that sbmA is involved in importantphysiological roles related to virulence.