Isolation and Characterization of a Lysogenic phage from Burkholderia pseudomallei (การแยกและลักษณะเฉพาะของ ไลโซเจนิกฝาจจากเชื้อ Burkholderia pseudomallei)

Abstract

Burkholderia pseudomallei is the causative agent of melioidosis, an infectious disease endemic in northeast Thailand. Lysogenic phages are viruses that integrated their DNA into host bacterial chromosomes. In this study, lysogenic phages were isolated from B. pseudomallei clinical isolates by mitomycin induction. Eighty percents of B. pseudomallei tested isolates produced phages. One of them, designated P27 was further characterized by electron microscopy, host range analysis, growth characteristic and genome restriction analysis. Transmission electron micrograph of P27 revealed that it possesses an isometric head of 73.33 nm in diameter with a non-contractile tail of 175 nm in length, which belong to the B1 morphotype of Siphoviridae family. This phage was able to lyse 51.1% of B. pseudomallei and 10% of B. thailandensis but not to B. mallei, E. coli, K. pneumoniae and P. aeruginosa. The nucleic acid of P27 was double stranded DNA with approximately 42.89 Kb. This phage demonstrated a short latent period (20 min) and small burst size (16 particles) resulting to observed small plaques of phage on the host.