Isolation and characterization of lytic bacteriophages specific for antibiotic-resistant Acinetobacter baumannii

Abstract

Almost all conventional antibiotics are no longer effective against the common nosocomial infection Acinetobacter baumannii. Bacteriophage therapy is an effective alternative for bacterial infections resistant to many drugs. In the present study, a lytic bacteriophage, ФEAP, which infects A. baumannii was chosen for characterization. Phage ФEAP described in this research has the ability to lysis A. baumannii that resists 94 % of the used antibiotics. A. baumannii isolated from a resistant wound abscess. When ФEAP alone incubated at different pH values and different temperatures, the phage was stable over a wide pH range (4 to 9) and at extreme temperatures (between 50°C and 60°C). In addition, ФEAP tolerates all concentrations of NaCl solutions used so it shows salinity tolerance and resistance to UV rays. ФEAP has a 94.4 nm icosahedral head and a 302 nm contractile tail. Pure concentrated phage was negatively stained and investigated using transmission electron microscopy (TEM). Electron micrographs showed that the phage belonged to a member of the Myoviridae family and the Caudovirales order. Bacteriophage