Identification and characterization of helveticin V-1829, a bacteriocin produced by Lactobacillus helveticus 1829

摘要: Lactobacillus helveticus 1829 produced an antimicrobial agent, designated helveticin V-1829, that demonstrated antagonistic activity against closely-related species. The agent was excreted into MRS agar, and present in the supernatant fluids from both overnight broth clotted milk cultures. It heat labile (inactivated by 50 degrees C for 30 min) stable over pH range 2.5 to 6.5. Production of substance pH-dependent maximum yields were obtained cultures maintained at 5.5. Helveticin V-1829 partially purified following growth producing strain a semi-defined medium precipitating cell-free filtrate with ammonium sulphate 30% saturation. cleared fluid then brought 60% saturation resulting precipitate pelleted dialysed 0.3 mol/l phosphate buffer. inhibitor sensitive several proteolytic enzymes, it bactericidal its mode action indicator cells Lact. 1844 delbrueckii subsp. bulgaricus 1489, indicating bacteriocin. A DNA probe specific J structural gene failed hybridize total genomic 1829, is not significantly related J.