Caracterización de bacteriocinas de Bacillus subtilis ATCC 6633 y Pseudomonas extremaustralis CMPUJ U515 en la perspectiva de control hacía patógenos humanos

Abstract

Bacteriocins comprise a large number of peptides synthesized ribosomically by countless numbers of bacteria. Biosynthesis is carried out by structural genes that encode these peptides. The increasing bacterial resistance threatens human and animal health. Bacillus subtilis has been shown to produce a wide range of bacteriocins. The genus Pseudomonas sp. synthesizes different antimicrobial peptides to dominate over other competing organisms. P. extremeustralis species is a non-pathogenic Gram-negative bacterium, isolated from a pond in the Antarctic Peninsula. Twenty-one bacteriocin sequences were identified in silico in the genome of B. Subtilis ATCC 6633 and two associated sequences in the genome of P. extremeustralis CMPUJ U515. The physicochemical properties allowed establishing the molecular weight, the isoelectric point, the positively and negatively charged residues, the extinction coefficient, the stability index, the aliphatic index and the overall average of hydropaticity (GRAVY). The products obtained from PCR, resulted in three products that correspond to the bacteriocins Subtilin, Sublancin 168 and Subtilocin A. Finally, it was desired to establish the possible growth inhibitory effect of the protein extracts of B. subtilis ATCC 6633 and P. extremaustralis CMPUJ U515, for which a qualitative sensidisk test was performed on the strains of Escherichia coli ATCC 25922 and Staphylococcus aureus CMPUJ 080. Unfortunately no activity was found. In this investigation we concluded that Bacillus subtilis ATCC 6633 has biocontrol potential due to its bacteriocins which can be cloned by homologous recombination into yeast, to analyze its biological functionality.