| Área: Microbiologia Clinica ( Divisão A ) DISTRIBUTION OF RIB GENE AMONG INVASIVE AND COLONIZING STREPTOCOCCUS AGALACTIAE (GBS)ISOLATES RECOVERED IN MISIONES, ARGENTINA Lacszeski Margarita (UNaM); Keil Angela (UNaM); Oviedo Patricia (UNaM); Quiroga Marina (UNaM); Pegels Eduardo (UNaM); Vergara Marta (UNaM)
ResumoGBS is an important cause of invasive infections in neonates. Several virulence factors have been identified and associated with the pathogenesis of GBS. Some serotypes, like III, V and Ia, are recognized as the major serotypes that cause invasive infections. It was reported that rib gene and Rib protein, encoded by rib gene, are present in the large majority of serotype III strains. Characterization of virulence-related genes of GBS isolates is considered as important since there is evidence that some proteins enconded by these genes may contribute to strain differences in virulence. Also, some of these proteins are immunogenic and they may play a future role in development of GBS vaccines.
This study is the first approach that we have done with the aim to contribute to a better understanding about the distribution of rib gene among invasive and colonizing GBS isolates recovered in Misiones, Argentina. Thirty-four GBS colonizing isolates recovered from vaginal-rectal swabs of pregnant women (gestation, 35–37 weeks) and 7 GBS isolates recovered from blood or cerebrospinal fluid of newborns were studied. rib gene was detected by specific PCR. PCR analysis revealed that 94.1% of the colonizing strains possessed the genes rib. Across invasive strains, rib gene was present in all of the isolates (100%). In agreement with others, we did not find rib gene more frequently in invasive versus colonizing GBS strains. The gene rib was found at higher frequency than in other studies. The difference could be caused by difference in the capsular serotype distribution of our GBS strains.
It was concluded that we needed more-extensive analysis of the virulence-related genes presents in our GBS isolates, including the relationship between rib gene and capsular serotype, to contribute with more useful epidemiological data.
Palavras-chave: rib gene, Streptococcus agalactiae, GBS |