Publication details

CHAP domain of tail-associated protein from phage 812 and its lytic activity against Staphylococcus aureus



Year of publication 2013
Type Conference abstract
MU Faculty or unit

Faculty of Science

Description Staphylococcus aureus is a major causative agent of human and animal diseases. The increasing number of pathogenic strains resistant to antimicrobial drugs is a serious public health problem that can be solved by applications of phage therapy as a suitable alternative to antibiotics treatment. Currently the research focus on the phage encoded antimicrobial proteins applicable to combat bacterial infections, such as phage endolysins that digest the cell wall of bacteria. In this study we focused on tail hydrolase of polyvalent staphylococcal bacteriophage 812, a member of SPO1-like viruses from family Myoviridae. This enzyme plays a role in the beginning of phage lytic cycle. It disturbs bacteria cell wall for injection of phage DNA into bacterial cell. CHAP domain was predicted at C-terminus of tail-associated protein by bioinformatics tools Total length of tail protein is 808 aa and CHAP domain is represented by 130 aa. The gene sequence for the CHAP domain was cloned and expressed as a soluble protein in E. coli. Expressed protein with his-tag was purified using metal-chelate affinity chromatography. Activity of this enzyme was verified on zymogram and using turbidity assay. Results show, that CHAP domain of tail-associated protein can lyse peptidogycan of S. aureus in zymograms. CHAP domain is also active against live bacterial cells and the protein decreas optical density of bacterial culture. Tail hydrolase is not as active like endolysin of phage 812. This problem can be resolved by modification of active site or by connecting CHAP domain with another domain.
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