The project is aimed at developing the scientific basis for the production and use of complex phage preparations, containing polysaccharide depolymerases (EPS depolymerases), for the biological control of E. amylovora. The idea of the work is based on the natural ability of phage EPS depolymerases to hydrolyze the capsule, one of the main virulence factors of the bacterial cell. The destruction of bacterial extracellular matrix causes an increase in sensitivity to external factors, loss of the ability to biofilm formation, as well as exposes the surface structures of the cell to the action of bacteriophages.
The work involves the search and characterization of new exopolysaccharide-depolymerase enzymes of phage origin, as a potential tool for biological control of E. amylovora, the causative agent of fire blight. It is expected that the following tasks will be performed: molecular genetic analysis of lytic erwiniaphages with EPS depolymerase activity, whole-genome sequencing and bioinformatics analysis of complete phage genome sequences, detection and characterization of genes with EPS-depolymerase activity; cloning of genes with EPS depolymerase activity, construction of producer strains, obtaining, purification and characterization of recombinant phage EPS depolymerases; investigation of the antagonistic effect of recombinant phage EPS depolymerases on E. amylovora strains in monotherapy, as well as in combination with lytic erwiniaphages.
Successful implementation of the project will provide new knowledge about erwiniaphages with EPS-depolymerase activity, persisting within Ukraine, as well as characterization of EPS depolymerases and evaluation of their effectiveness in controlling the causative agent of fire blight. The development of such approaches to biological control has no analogs in Ukraine.