Bacteriophages (phages) are considered as natural therapeutic agents to control bacterial infections. They are safe for host and highly specific to the targeted bacteria. Aeromonas hydrophila is a motile aeromonad that can cause disease in fish known as "Motile Aeromonas Septicemia" (MAS). In this study, we described the isolation and characterization of a phage, designated pAh-1 which infects A. hydrophila. The pAh-1 was isolated from stream water near Yuseong-gu, Daejeon, Korea after enrichment with A. hydrophila followed by soft agar overlay method. The isolated pAh-1 was morphologically classified as a member of Myoviridae family. pAh-1 showed efficient bacteriolytic activity against A. hydrophila and A. salmonocida salmonicida however, host range was narrow. Single-step growth curve results revealed that latent period of pAh-1 was estimated to be approximately 30 min while the burst size was 75 PFU/cell. The adsorption rate of the pAh-1 was significantly enhanced by the addition of 10 mM CaCl2 and 10 mM MgSO4. The pH stability result indicates that optimum pH for pAh-1 ranged between 7 to 11. Also, pAh-1 showed thermal stability up to 40 °C. Single administration of pAh-1 to zebrafish (Danio rerio) resulted in moderate protective effects on survival rate against A. hydrophila challenge. These results suggest that the pAh-1 is a potential phage as biocontrol agent for treatment of A. hydrophila infection in fish.
Isolation and characterization of a virulent bacteriophage specific to Aeromonas hydrophila
FRONTE, BALDASSARE;
2015-01-01
Abstract
Bacteriophages (phages) are considered as natural therapeutic agents to control bacterial infections. They are safe for host and highly specific to the targeted bacteria. Aeromonas hydrophila is a motile aeromonad that can cause disease in fish known as "Motile Aeromonas Septicemia" (MAS). In this study, we described the isolation and characterization of a phage, designated pAh-1 which infects A. hydrophila. The pAh-1 was isolated from stream water near Yuseong-gu, Daejeon, Korea after enrichment with A. hydrophila followed by soft agar overlay method. The isolated pAh-1 was morphologically classified as a member of Myoviridae family. pAh-1 showed efficient bacteriolytic activity against A. hydrophila and A. salmonocida salmonicida however, host range was narrow. Single-step growth curve results revealed that latent period of pAh-1 was estimated to be approximately 30 min while the burst size was 75 PFU/cell. The adsorption rate of the pAh-1 was significantly enhanced by the addition of 10 mM CaCl2 and 10 mM MgSO4. The pH stability result indicates that optimum pH for pAh-1 ranged between 7 to 11. Also, pAh-1 showed thermal stability up to 40 °C. Single administration of pAh-1 to zebrafish (Danio rerio) resulted in moderate protective effects on survival rate against A. hydrophila challenge. These results suggest that the pAh-1 is a potential phage as biocontrol agent for treatment of A. hydrophila infection in fish.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
