DAO 108:23-35 (2014)  -  DOI: https://doi.org/10.3354/dao02687

Edwardsiella piscicida identified in the southeastern USA by gyrB sequence, species-specific and repetitive sequence-mediated PCR

Matt J. Griffin1,*, Cynthia Ware1, Sylvie M. Quiniou2, James M. Steadman1, Patricia S. Gaunt1, Lester H. Khoo1, Esteban Soto3

1Aquatic Research and Diagnostic Laboratory, Thad Cochran National Warmwater Aquaculture Center, College of Veterinary Medicine, Mississippi State University, PO Box 197, 127 Experiment Station Road, Stoneville, Mississippi 38776, USA
2Warmwater Aquaculture Research Unit, Thad Cochran National Warmwater Aquaculture Center, USDA-ARS, PO Box 38, Stoneville, Mississippi 38776, USA
3Marine Research Laboratory, Department of Pathobiology, School of Veterinary Medicine, Ross University, Basseterre, St. Kitts, West Indies
*Corresponding author:

ABSTRACT: A new Edwardsiella taxon was recently described from fishes of Europe and Asia. Phenotypically similar to E. tarda, extensive genetic and phenotypic characterization determined this new strain does not belong to any established Edwardsiella taxa, leading to the adoption of a new taxon, E. piscicida. Concurrent research in the USA also identified 2 genetically distinct taxa within the group of organisms traditionally classified as E. tarda. Comparisons of gyrB sequences between US isolates and E. piscicida from Europe and Asia identified several US isolates with >99.6% similarity to the gyrB sequence of the E. piscicida type strain (ET883) but <87% similarity to the E. tarda type strain (ATCC #15947). A discriminatory PCR was developed for the identification of E. tarda and 2 genetic variants of E. piscicida (E. piscicida and E. piscicida-like species). Using these PCR assays, a survey was conducted of 44 archived bacterial specimens from disease case submissions to the Aquatic Research and Diagnostic Laboratory (Stoneville, MS, USA) between 2007 and 2012. All 44 isolates, originally identified phenotypically and biochemically as E. tarda, were identified as E. piscicida by PCR. Repetitive sequence-mediated PCR (rep-PCR) analysis of these archived specimens suggests they are largely homogenous, similar to what has been observed for E. ictaluri. The gyrB sequence data, coupled with the E. piscicida specific-PCR and rep-PCR data, confirms that E. piscicida has been isolated from fish disease cases in the southeastern USA. Moreover, our survey data suggests E. piscicida may be more prevalent in catfish aquaculture than E. tarda


KEY WORDS: Edwardsiella tarda · E. piscicida · gyrB · PCR · Repetitive sequence-mediated PCR · Rep-PCR


Full text in pdf format 
Cite this article as: Griffin MJ, Ware C, Quiniou SM, Steadman JM, Gaunt PS, Khoo LH, Soto E (2014) Edwardsiella piscicida identified in the southeastern USA by gyrB sequence, species-specific and repetitive sequence-mediated PCR. Dis Aquat Org 108:23-35. https://doi.org/10.3354/dao02687

Export citation
Mail this link - Contents Mailing Lists - RSS
- -