title: Identification and characterization of bacteriophages specific to the catfish pathogen, Edwardsiella ictaluri.
abstract: OBJECTIVE
  To identify and characterize bacteriophages specific for Edwardsiella ictaluri, the causative agent for enteric septicemia of catfish (ESC).
  
  
  RESULTS
  Two bacteriophages were isolated that infect Edw. ictaluri. They both produce clear plaques, have icosahedral heads with a non-rigid tail, and are tentatively classified as Siphoviridae. Phages PhieiDWF and PhieiAU are dsDNA viruses with approximate genome sizes of 40 and 45 kb, respectively. The addition of 500 micromol l(-1) CaCl(2) enhanced phage titres. Both phages have a latent period of 40 min and an estimated burst size of 270. Every Edw. ictaluri strain tested was susceptible to phage infection with variable plaquing efficiencies and with no evidence of lysogeny, with no plaques detected on other bacterial species.
  
  
  CONCLUSIONS
  Two unique bacteriophages were isolated that show host-specificity for Edw. ictaluri, have temperature and metal cation-dependent infectivity, and are tentatively placed within the family Siphoviridae.
  
  
  CONCLUSIONS
  This is the first report of bacteriophages specific to Edw. ictaluri, an important fish pathogen affecting farm-raised channel catfish. Initial characterization of these bacteriophages has demonstrated their potential use as biotherapeutic and diagnostic agents associated with ESC.
authors.affiliation: Department of Fisheries and Allied Aquaculture, Auburn University, Auburn, AL 36849, USA.
authors.forename: J K
authors.initials: JK
authors.lastname: Walakira
authors.forename: A A
authors.initials: AA
authors.lastname: Carrias
authors.forename: M J
authors.initials: MJ
authors.lastname: Hossain
authors.forename: E
authors.initials: E
authors.lastname: Jones
authors.forename: J S
authors.initials: JS
authors.lastname: Terhune
authors.forename: M R
authors.initials: MR
authors.lastname: Liles
mesh_terms: D000818:Animals; D001435:Bacteriophages / Q000254:growth & development / Q000302:isolation & purification*; D002118:Calcium; D002397:Catfishes; D020610:Edwardsiella ictaluri / Q000821:virology*; D005393:Fish Diseases / Q000382:microbiology; D006790:Host-Parasite Interactions; D008274:Magnesium; D008854:Microscopy, Electron; D013696:Temperature
chemical_list: D008274:Magnesium; D002118:Calcium