Study the Bacteriocin Production from Enterococcus Faecium Isolated From Clinical Sources

Abstract

Two hundred ninety clinical samples were collected from patients of Baghdad hospitals,distributed into(177) urine and (113) stool samples.Bacteriological and biochemical detection tests showed that only 27 isolates (9.31%) were identified as Enterococcus faecium.Antimicrobial susceptibility results showed a high resistance to Nalidixic acid (81%) and Tetracycline (63%) ,while (48%) of the isolates were resistant to Ciprofloxacin. E.faecium showed low resistance to Trimethoprime (19%) and (7%) to Gentamycin. All isolates produce bacteriocin (100%) with a wide range effect on gram positive and negative bacterial growth,with diameter of inhibition zones (8-15)mm and (9-27)mm on the same isolates of species. E.faecium EH1 chosen as the best producer and solid and broth Man Ragusa sharp medium was the best medium for production at )16-45(Cº.Crude bacteriocin was stable at temperature(80,100,121Cº) for (15 ,30) minutes and in pH range (2-8) and storage in temperature (0,4Cº,37) for week.Partial purification with ammonium sulphate in percentage 40% was the best with a specific activity (44.137)unit /mg protein and protein concentration (290)mg/ml.The partial purified bacteriocin was stable at 80Cºfor 30 minutes and 100Cº for( 5,15) minutes.Its activity was stable in pH (5.5-8.5) and storage at 0Cº for week.