Merlich A. Characterization of Enterococcus italicus ONU547 strain bacteriocin producer

The work is dedicated to characterization of the strain Enterococcus italicus ОNU547, which is able to produce a bacteriocin and also to study of properties of the bacteriocin. Tinctorial, morphological, cultural, biochemical, physiological biochemical and genetic properties of bacteria of the isolated strain of bacteriocin producer were studied and it was identified as belonging to the species E. italicus. It was determined that L-glutamic acid (12,68%), L-arginin (16,56%) and glycine (16,47%) compose cells of E. italicus ONU547 in the biggest quantity among amino acids and glucose (87,77%) - among sugars. Presence of acetic acid in cultural liquid of E. italicus ONU547 was revealed. Bacteriocin of E. italicus ONU547 was characterized and its hydrophobicity, cationic nature, two component structure (or there are two bacteriocins), thermostability, inhibitory activity against bacteria causing food spoilage, opportunistic bacteria, and also their biofilms were established. Production of new bacteriocin for the species E. italicus was showed. Ability of bacteria of the strain E. italicus ONU547 to inhibit growth of phytopathogenic bacteria Rhizobium radiobacter C58 and Erwinia carotovora ZM1 in vivo and, moreover, to form biofilms on plant surfaces were established. These last two properties they exhibit as separately as well as in complexes with bacteria Lactobacillus plantarum ОNU12 and Lactobacillus plantarum ОNU311.