BIOCHEMICAL STUDY OF A NOVEL MICROCIN PRODUCED BY A CLINICAL ISOLATE OF Shigella flexneri 2

MONICA FLORENCIA TORREZ LAMBERTI; LUCAS DÍAZ FERNÁNDEZ; MARÍA DE LAS MERCEDES PESCARETTI; MÓNICA A. DELGADO

San Luis

Congreso; SAMIGE; 2018

The enterobacterial have the ability to produce antimicrobial peptides called bacteriocins with the aim to prosper in the host intestine. Shigella is the most common agent of diarrhea, an important worldwide health problem. Previously, we report a new low molecular weight bacteriocin produced by a Shigella flexneri 2 CI172 strain and isolated from fecal sample of a children suffering acute diarrhea. This is the first report where a Shigella flexneri microcin-producer is described, suggesting that the appearance of this strains is not common. Here, we enhance the characterization of this antimicrobial peptide. We performed cross-streaking tests in order to analyze whether the CI172 strain display immunity to other microcin groups. Moreover, we the ShpCI172 cell-free supernatant was subjected to a first purification step with ammonium sulfate precipitation and then, to a second purification step with acetone precipitation. Finally, was improved an HPLC analysis. The ShpCI172 is a novel characterized antimicrobial peptide that may contribute to prevent or control diarrhea diseases.