Nucleic Acid and Protein Profile of Bacteriophages that Infect Pseudomonas syringae pv. glycinea, Bacterial Blight on Soybean

Several management strategies of Bacterial blight disease caused by Pseudomonas syringae pv. glycinea has been developing to minimize yield loss including the use of bacteriophage as phage therapy. However, some consideration must be point on its interaction with bacterial host and influence of bacterial host virulence. Therefor, information of characteristic of prospective bacteriophage must be determined prior to use as biological control agent. This research aimed to obtain some information about general characteristics of bacteriophage that infects P. syringae pv. glycinea such as the ability in propagation in bacterial host, type of nucleic acid, and total protein profile. The results showed that about four bacteriophages have been isolated from soybean soil in Sukorambi and Mangli area named ϕSK2a, ϕSK2b, ϕSK2c (from Sukorambi), and ϕMGX1 (from Mangli). All phages had different ability in propagation in bacterial host, P. syringae pv. glycinea strain H3 about 10¹⁰-10¹² PFU/mL. Nucleic acid analysis using digestion enzymes (DNase, RNase, and Restriction endonuclease) showed that all bacteriophage isolates had double stranded deoxyribonucleic acid (dsDNA). Moreover, protein profile of bacteriophage through sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed that all phages had similar pattern of the protein suggested the same type of bacteriophage. However, morphological characteristic is still needed to accurate determination of bacteriophage taxonomy.