The bbk32 gene was amplified from B31 genomic DNA, however, PCR product was not detected in the N40D10/E9 strain. (B) Southern blot of EcoR1-digested genomic DNA of both strains (top) was hybridized with the probe prepared
using the bbk32 PCR product from B31. An approximately 1.8 kb size fragment was detected only in B31, as expected, but not in the N40D10/E9 genomic DNA containing lane. In another study, we compared two important, highly variable virulence factors of B. burgdorferi, OspC and DbpA. As expected, both of these selleck chemicals llc molecules are present in both spirochete strains but showed high sequence variation . Therefore, irrespective of the phylogenetic grouping of these strains using RST and OspC categorization, the presence of known virulence factors in both strains suggests that B31 and N40D10/E9 could possibly exhibit similar levels of pathogenicity. Furthermore, although BBK32 is an adhesin , previous
studies showed that its absence results in a subtle infectivity defect, exhibiting disease attenuation only at low dose of infection [45, 102, 103]. Divergence of fibronectin-binding adhesin gene bbk32 in N40D10/E9 strain BBK32 could possibly www.selleckchem.com/products/Imatinib-Mesylate.html contribute to the adherence-mediated tissue colonization in B31 as compared to N40D10/E9 strain but a negative PCR result is not sufficient to demonstrate this difference. Since sequence divergence at the priming sites may lead to unsuccessful PCR amplification, Southern hybridization was conducted to determine the presence of a homolog of bbk32 gene in the N40D10/E9 strain. Absence of a band in N40
even under low stringency conditions (data not shown) indicated that either bbk32 homolog in the N40D10/E9 strain was absent or had substantial Bortezomib nmr DNA sequence divergence from that in the B31 strain (Figure 3B). Therefore, irrespective of the presence of BBK32, the two B. burgdorferi strains examined here (B31 and N40D10/E9) show similar levels of binding to most cells, indicating redundancy of function. However, BBK32 may contribute to the binding of Lyme spirochetes to specific cell line(s), such as Vero cells, and potentially to epithelial cells in vivo. B31 and N40D10/E9 showed remarkably different protein expression profiles Although known virulence factors are present in both B31 and N40D10/E9 strains (Figure 3A), they only represent the molecular profile of previously identified virulence factors and molecules associated with infectivity. Therefore, it would be erroneous to conclude that they represent the full repertoire of the virulence factors of B. burgdorferi that play important roles during pathogenesis in the mammalian host.