Two novel thermally resistant endolysins encoded by pseudo T-even bacteriophages RB43 and RB49.

Identification and cloning of genes as well as biochemical characterization of the gene products were carried out for two novel endolysins of pseudo T-even lytic bacteriophages RB43 and RB49, which represent different myovirus groups of the subfamily . Genes RB43ORF159c and RB49р102 were cloned in cells, and their products were purified to electrophoretic homogeneity with an up to 80 % yield of total activity. In respect to substrate specificity, both enzymes were found to be lytic l-alanoyl-d-glutamate peptidases belonging to the M15 family.

In vitro study of the antibacterial effect of the bacteriophage T5 thermostable endolysin on Escherichia coli cells.

Aims: This study aimed to evaluate lysis of Escherichia coli stationary cell cultures induced by the combined action of bacteriophage T5 endolysin (l-alanyl-d-glutamate peptidase) and low doses of various cationic agents permeabilizing the outer membrane of Gram-negative bacteria (polymyxin B, gramicidin D, poly-l-lysine, chlorhexidine and miramistin).

Methods And Results: The enzyme activity was assayed with the turbidimetric method. Antimicrobial activity was assessed through the number of colony-forming units (CFUs); the results of calculation were represented as logarithmic units.