Submitted to: American Society for Microbiology Branch Meeting
Publication Type: Abstract only
Publication Acceptance Date: 10/18/2004
Publication Date: 10/22/2004
Citation: Panangala, V.S., Shoemaker, C.A., Vansanten, V., Mcnulty, S.T., Arias, C. 2004. Polyphasic characterization of edwardsiella ictaluri and e. tarda isolates from fish. American Society for Microbiology Branch Meeting. Interpretive Summary:
Technical Abstract: Edwardsiella ictaluri, a catfish pathogen is the cause of enteric septicemia in catfish and E. tarda predominantly an enteric pathogen of marine and fresh water fish has a broader host range. Phenotypic characterization of 18 E. ictaluri and 9, E .tarda on the basis of sodium dodecyl sulfate - polyacrylamide gel electrophoresis profiles, outer membrane antigens and fatty acid methyl esters revealed a high degree of similarity among E. ictaluri but distinctive differences among E. tarda isolates. Genotypically, rDNA sequence alignment revealed that five of the E. ictaluri isolates, each exhibited marked heterogeneity at four nucleotide positions in the intergenic spacer region (ISR). The sequences of the remaining thirteen E. ictaluri were relatively homogeneous. The sequences of the smaller ISR of the E. tarda isolates were 97% identical to the E. ictaluri sequences, while the larger ISR's were 96-98% identical. Among the E .tarda isolates, there was 97% identity. Polyphasic characterization presents a stable and reliable means for detection of inter and intra species heterogeneity among Edwardsiella isolates.