Isolation and characterization of bacteriophages against enterotoxigenic Escherichia coli strains causing swine diseases

Xuan Hoa Nguyen, Tang Fang, Bai Qinqin, Shen Chanjuan, Thin Vo Thanh, Lu Chengping
2013 African Journal of Microbiology Research  
Six lytic bacteriophages (JH1-JH6) lytic against O8 ETEC were isolated from 40 individual fecal samples and 30 sewage samples from pig farms in Nanjing, China. Two of the bacteriophages (JH1 and JH2) with icosahedral heads, necks, contractile tails belonged to the Myoviridae family. The other four bacteriophages (JH3, JH4, JH5 and JH6) had relatively thin, long, non-contractile and belonged to the Siphoviridae family. Unlike typical Siphoviridae family members' morphologyes had flexible tails,
more » ... hereas JH5 had the straight tails and fibers. All bacteriophages produced clear plaques in double agar, with JH6 producing the largest plaques. Phages JH1 to JH6 lysed 50 to 100% of 12 O8: F18 ETEC strains, 50 to 75% of 20 O8:F4 ETEC, 5 to 42.5% of 40 non-O8 ETEC and 4.76 to 9.52% of 21 chickens E. coli strains. No lysis of E. coli strain from cows, as well as Escherichia coli in other O serogroups (O2, O5, O9, O11, O138, O139, O141 and O149), was observed. All bacteriophages titers were unaffected by exposure to pH 5 to 9 for 16 h. Sodium dodecyl sulphate-polyacrilamide gel electrophoresis (SDS-PAGE) obtained from proteins was extracted from the various bacteriophages. The proteomes of JH1 and JH2 appear to be identical while that of the other four phages are all different indicating they are probably different. These six bacteriophages are potential candidates for prophylaxis and therapeutic strategies against diarrhea in piglets caused by O8 ETEC.
doi:10.5897/ajmr2013.5744 fatcat:ukkx6mbrafbm3cuqtlvlc7qjta