Colisepticemia is one of the major problems of modern medicine, the treatment cost billions of dollars and causes hundreds of thousands mortality cases annually. Colisepticemia is caused by strains that can grow in blood.
Our research is focused on the iss locus of plasmid ColV and its homologous chromosomal bor gene, both of them closely related to a previously identified gene of phage lambda that is expressed during lysogeny. There is a high homology between Bor and Iss proteins (95%) and regulatory regions (81%), however only strains that have both bor and iss genes can survive in human serum.
In this work we characterize the conditions that promote iss and bor expression using lacZ as a reporting gene. The activity of the promoters is determined in K-12 and O78 E.coli strains. The results indicate that the expression profile of these genes is unique for each of the bacterial strains.
