Abstract

Bacteriophages have varied practical applications, so we did a basic study of the characteristics of an isolated phage against Brucella abortus for proper understanding of its general properties. Bacteriophage against B. abortus strain 19 was isolated from the sewage samples. Structural protein profiling of the isolated brucellaphage by SDS-PAGE revealed 4 bands of molecular weight: 65.98, 60.46, 48.56 and 43.97 kDa. The brucellaphage was susceptible to heat at and above 60°C temperature. Exposure to sunlight gradually decreased the phage concentration within 3 h. Ultraviolent light (UV) completely inactivated phage within 3 min of exposure. The brucellaphage was susceptible to pH 2, 4 and 10, whereas pH 6 and 8 did not affect the phage activity. The phage was sensitive to SDS, phenol, chloroform, iodine, benzalkonium and formalin, whereas it was insensitive to EDTA treatment. Lysozyme completely inactivated the phage within one hour, while only 0.51% phage survival was observed in the presence of trypsin within 3 h, whereas RNase treatment did not affect the phage titre. The phage isolated was Brucella specific and did not lyse any of the heterologous bacterial species tested. The phage lysed B. abortus vaccine strains S19 and S99; Brucella melitensis andB. abortus field isolates.

Key words: Brucellaphage, Brucella abortus strain 19, physicochemical characterization.