A conserved hypothetical protein of Brucella spp is essential for their virulence in animals

CARRICA M; CRAVERO S

Chicago

Conferencia; 59th Annual Brucellosis Research Conference; 2006

By gene inactivation and allelic exchange in Brucella abortus S2308, B. melitensis 16M and B. suis 1330, we identify the B. melitensis BMEI0489 ORF as being essential for their virulence, and we named this ORF as iivA. This ORF encodes a hypothetical conserved protein of 106 amino acids that belongs to the Cluster of Orthologous Group (COG) 2960 that belongs to a family of uncharacterized proteins currently contains 126 members. IivA is trimeric in solution, with a coiled-coil domain in its carboxy-terminal and an unstructured amino-terminal. The B. abortus S2308 and its knock-out mutant grow at a similar rate in vitro. The mutant is protective in the mice model against a challenge with S2308. A Salmonella typhimurium knock-out mutant in the orthologous gene of BMEI0489 is attenuated in the mice model. We are trying to define the biochemical function of IivA through its protein structure.