Escherichia coli strains that cause diseases outside the intestine are known as extra intestinal pathogenic E. coli (ExPEC) which includes human uropathogenic E. coli (UPEC) and avian pathogenic E. coli (APEC). Our group has been working, for several years, in the study of APECs, in order to characterize these types of bacteria strains for their biological characteristics related to pathogenicity. Recently, it was demonstrated that different types of extracellular signs regulate gene expression in bacteria. When the sign is produced by the bacteria, the process is called quorum sensing (QS) (Anand e Griffiths, 2003). Pathogenic bacteria, through quorum sensing, can achieve high cell density and produce virulence factors enough to surpass the host defenses, before of the possible immunological system recognition (De Kievit et al., 2001). For all we know, there is no work being realized with APEC strains in Brazil and abroad, where the regulation function of the quorum sensing system, about the general mechanisms of gene expression, including those related to pathogenicity, is being studied. This context led to this proposal, that aims to study the effects of a gene of AI-2 quorum sensing system in the global gene expression, including those possibly related to pathogenicity of APEC, and the changes in biological properties presents in the strain.
News published in Agência FAPESP Newsletter about the scholarship: