Comparative Analysis of Virulence Profiles of Isolated from Diverse Clinical Origins in Mexican Patients.

is an enteric bacterium with increasing incidence in clinical settings, attributed mainly to the opportune expression of diverse virulence determinants plus a wide intrinsic and acquired antibiotic resistance. The aim of this study was to compare the virulence factor profiles of 185 isolates from different clinical origins. In vitro proteolytic and hemolytic activities, biofilm formation, and motility were assessed in each strain. Additionally, the pathogenicity of four hypervirulent strains was analyzed in vivo in . We found that bacterial isolates from wound/abscess and respiratory tract specimens exhibited the highest protease activity along with a strong biofilm production, while uropathogenic isolates showed the highest hemolytic activity. Swarming and swimming motilities were similar among all the strains. However, respiratory tract isolates showed the most efficient motility. Two hyperhemolytic and two hyperproteolytic strains were detected; the latter were more efficient killing with a 50%-60% larval mortality 48 hours after challenge. A correlation was found between biofilm formation and proteolytic and hemolytic activities in biopsy specimens and bloodstream isolates, respectively. Overall, it becomes critical to evaluate and compare the clinical strains virulence diversity in order to understand the underlying mechanisms that allow the establishment and persistence of opportunistic bacterial infections in the host.