Molecular screening of the entA gene of Enterococcus faecium isolated from Food and clinical sources

Background: The microbial production of substances that have the potency to suppress the growth of other microorganisms is probably one of the prevalent defense strategy developed in nature, microorganisms produce a variable bunch of microbial defense systems, which include antibiotics, metabolic by-products, lytic agents, bacteriocins and others. Objective: The purpose of the present study was to isolate and identify Enterococcus faecium isolates then detecting its ability of carrying the gene responsible for enterocin production in this species. Materials and methods: Out of 50 samples from different sources (food and clinical sources) were collected for the Enterococcus faecium isolation, and the isolated bacteria Enterococcus faecium (37) isolates were detected for their harboring of Enterocin A gene (entA), using conventional PCR technique. Results: The identification revealed that 37(74%) isolates were considered as Enterococcus faecium, 20 isolates (54.05%) out of food samples (10 samples were collected from dairies, 7 from vegetables and 3 from fish samples), and 17 isolates 45.9% out of clinical samples (11 from stool and 6 from urine source). Genotypic Detection done by the amplification of the enterocin coding gene (ent A),  and the results revealed that all the isolates were harboring that gene despite of the phonotypical differences, that they amplified entA gene and the PCR product size (362 bp) was detected using agarose gel electrophoresis. Conclusions: This study indicates the presence of Enterococcus spp. in food and clinical sources and the ability of these bacteria to produce antibacterial substances which is active against closely related clinical isolates.