In silico and experimental analysis of the repeated domains in BvaP, a protein important for GBS vaginal colonization.

Streptococcus agalactiae (group B strep, GBS) infections in neonates are often fatal and strongly associated with maternal GBS vaginal colonization. Previously, we highlighted the importance of a formerly uncharacterized protein, BvaP, in GBS vaginal colonization. BvaP is highly conserved across GBS and is made up of repeated domains, with a variable number of repeats between strains. Here, we evaluate the prevalence of BvaP repeated domains and their relevance in phenotypes previously associated with vaginal colonization. Using in silico analysis, we found that the number of repeats in the BvaP protein does not generally appear to be associated with serotype, isolation site, or host. Using BvaP truncations in GBS strain A909, we determined that a smaller number of repeats was correlated with decreased bacterial chain length, but adherence to vaginal epithelial cells was complemented using BvaP containing one, two, three, or five repeats. Future research will be geared toward understanding the host immune response to BvaP in vivo and whether vaginal carriage or host response is dependent on the BvaP repeated domains.

Quinovic acid purified from medicinal plant Fagonia indica mediates anticancer effects via death receptor 5.

Plants are major source for discovery and development of anticancer drugs. Several plant-based anticancer drugs are currently in clinical use. Fagonia indica is a plant of medicinal value in the South Asian countries. Using mass spectrometry and NMR spectroscopy, several compounds were purified from the F. indica extract. We have used one of the purified compounds quinovic acid (QA) and found that QA strongly suppressed the growth and viability of human breast and lung cancer cells. QA did not inhibit growth and viability of non-tumorigenic breast cells. QA mediated its anticancer effects by inducing cell death. QA-induced cell death was associated with biochemical features of apoptosis such as activation of caspases 3 and 8 as well as PARP cleavage. QA also upregulated mRNA and protein levels of death receptor 5 (DR5). Further investigation revealed that QA did not alter DR5 gene promoter activity, but enhanced DR5 mRNA and protein stabilities. DR5 is one of the major components of the extrinsic pathway of apoptosis. Accordingly, Apo2L/TRAIL, the DR5 ligand, potentiated the anticancer effects of QA. Our results indicate that QA mediates its anticancer effects, at least in part, by engaging DR5-depentent pathway to induce apoptosis. Based on our results, we propose that QA in combination with Apo2L/TRAIL can be further investigated as a novel therapeutic approach for breast and lung cancers.