Antimicrobial peptides are small molecules that exhibit strong antagonistic activity against pathogenic microorganisms and are synthesized by a wide variety or organisms, including probiotic bacteria. The aim of the study was to identify peptides with antimicrobial activity in the Enterococcus faecium IP5-2a strain previously isolated from the intestinal tract of Nile tilapia (Oreochromis niloticus). Cellular and extracelullar proteins extraction was performed, followed by 1D SDS-PAGE gel electrophoresis and MALDI-TOF/TOF mass spectrometry. The results revealed peptides with antimicrobial activity, including P54 (SagA) protein, a bacteriocin-like protein and a lantibiotic. These proteins play an important role in the antagonistic capacity of the E. faecium IP52a strain, allowing it to be considered as a potential probiotic in the aquaculture industry.

Probiotic bacteria in aquaculture represent a control alternative and prevention of pathogens, in addition, reduce the use of antibiotics. However, it is necessary to search for other groups of bacteria with similar or better properties, obtained even from the same source. The aim of the study was to identify molecularly lactic acid bacteria with probiotic properties isolated from the posterior intestine of Nile tilapia (Oreochromis niloticus). The study was carried out from November 2017 to March 2018 evaluating the antagonistic, proteolytic, amylolytic, and antibiotic sensitivity activities, and antagonistic to the following pathogens: Aeromonas hydrophila, Aeromonas veronii, Pseudomonas aeruginosa, Pseudomonas putida and Plesiomonas shigelloides. It was identified by sequencing the 16S rRNA gene that Enterococcus faecium (IP5-2a) and Pedioc...

Probiotic bacteria in aquaculture represent a control alternative and prevention of pathogens, in addition, reduce the use of antibiotics. However, it is necessary to search for other groups of bacteria with similar or better properties, obtained even from the same source. The aim of the study was to identify molecularly lactic acid bacteria with probiotic properties isolated from the posterior intestine of Nile tilapia (Oreochromis niloticus). The study was carried out from November 2017 to March 2018 evaluating the antagonistic, proteolytic, amylolytic, and antibiotic sensitivity activities, and antagonistic to the following pathogens: Aeromonas hydrophila, Aeromonas veronii, Pseudomonas aeruginosa, Pseudomonas putida and Plesiomonas shigelloides. It was identified by sequencing the 16S rRNA gene that Enterococcus faecium (IP5-2a) and Pedioc...

Probiotic bacteria in aquaculture represent a control alternative and prevention of pathogens, in addition, reduce the use of antibiotics. However, it is necessary to search for other groups of bacteria with similar or better properties, obtained even from the same source. The aim of the study was to identify molecularly lactic acid bacteria with probiotic properties isolated from the posterior intestine of Nile tilapia (Oreochromis niloticus). The study was carried out from November 2017 to March 2018 evaluating the antagonistic, proteolytic, amylolytic, and antibiotic sensitivity activities, and antagonistic to the following pathogens: Aeromonas hydrophila, Aeromonas veronii, Pseudomonas aeruginosa, Pseudomonas putida and Plesiomonas shigelloides. It was identified by sequencing the 16S rRNA gene that Enterococcus faecium (IP5-2a) and Pedioc...

Probiotic bacteria in aquaculture represent a control alternative and prevention of pathogens, in addition, reduce the use of antibiotics. However, it is necessary to search for other groups of bacteria with similar or better properties, obtained even from the same source. The aim of the study was to identify molecularly lactic acid bacteria with probiotic properties isolated from the posterior intestine of Nile tilapia (Oreochromis niloticus). The study was carried out from November 2017 to March 2018 evaluating the antagonistic, proteolytic, amylolytic, and antibiotic sensitivity activities, and antagonistic to the following pathogens: Aeromonas hydrophila, Aeromonas veronii, Pseudomonas aeruginosa, Pseudomonas putida and Plesiomonas shigelloides. It was identified by sequencing the 16S rRNA gene that Enterococcus faecium (IP5-2a) and Pedioc...

The characteristics of a strain of Bacillus amyloliquefaciens isolated from the intestine of Arapaima gigas, selected for its ability to generate inhibition of multiple pathogenic bacteria of fishes were analyzed by using molecular tools such as PCR and mass spectrometry - MALDI TOF / TOFM. The results showed through PCR that this strain has key genes for the generation of antimicrobial peptides such as bmyB (bacillomycin L synthetase B), fenD (fengycin synthetase), srfAA (subunit 1 surfactin synthetase), bacA (bacilysin biosynthesis protein) and iturin (iturin A). In addition, by mass spectrometry analysis were detected bacteriocins (plipastatin, gramicidin, fengycin, surfactin), intestine binding proteins (like-enolase), antimicrobial peptide transport proteins (ABC-transporters) and immune system stimulation proteins like flagelin. Collagenase, chitinases and xylose-isomerases protein...

Se analizaron las características de una cepa de Bacillus amyloliquefaciens aislada del intestino de Arapaima gigas, seleccionada por su capacidad para generar inhibición de múltiples bacterias patógenas de peces, mediante el uso de herramientas moleculares como PCR y espectrometría de masas - MALDI TOF/TOF. Los resultados mostraron a través de PCR que esta cepa cuenta con genes claves para la generación de péptidos antimicrobianos como bmyB (bacillomycin L synthetase B), fenD (fengycin sintetasa), srfAA (subunidad 1 surfactin sintetasa), bacA (proteína de biosíntesis de bacilysin) e iturin (iturin A). Además, mediante el análisis por espectrometría de masas se detectaron bacteriocinas (plipastatin, gramicidin, fengycin, surfactin), proteínas de fijación al intestino (like-enolase), proteinas transportadoras de péptidos antimicrobianos (ABC-transporters) y proteínas de e...

The aim of this study was to characterize the PepT1 of pirarucu Arapaima gigas through genomic and proteomic tools. A transcriptomic and proteomic analysis was made from sections of the intestine, spleen, liver and kidney of fingerlings. The transcriptomic analysis allowed obtaining two consensus sequences of 357 and 459 bp. Both fragments showed a high degree of homology (78 and 80%), mainly with nucleotide sequences coding for the PepT1 of Scleropages formosus of the same Order as A. gigas. The proteomic analysis by double mass spectrometry MALDI TOF/TOF allowed to identify 15 peptide sequences of PepT1 in pirarucu. In conclusion, PepT1 was partially characterized in the intestine of pirarucu, which could be used for further studies on the evaluation of its expression.

El objetivo del estudio fue caracterizar el PepT1 del paiche Arapaima gigas mediante herramientas genómicas y proteómicas. Se realizó un análisis transcriptómico y proteómico a partir de secciones del intestino, bazo, hígado y riñón de alevines. El análisis transcriptómico permitió obtener dos secuencias consenso de 357 y 459 pb. Ambos fragmentos presentaron un alto grado de homología (78 y 80%), principalmente con secuencias de nucleótidos codificantes del PepT1 de Scleropages formosus del mismo Orden que el paiche. El análisis proteómico por espectrometría de doble masa MALDI TOF/TOF permitió identificar quince secuencias peptídicas del PepT1 en paiche. Como conclusión se logró caracterizar parcialmente el PepT1 en el intestino del paiche, las cuales podrán ser usadas para posteriores estudios sobre la evaluación de su expresión.