Identification and virulence of Chryseobacterium indologenes isolated from diseased yellow perch (Perca flavescens)
Article first published online: 21 DEC 2012
© 2012 No claim to US Government works
Journal of Applied Microbiology
Volume 114, Issue 3, pages 636–643, March 2013
How to Cite
Pridgeon, J.W., Klesius, P.H. and Garcia, J.C. (2013), Identification and virulence of Chryseobacterium indologenes isolated from diseased yellow perch (Perca flavescens). Journal of Applied Microbiology, 114: 636–643. doi: 10.1111/jam.12070
- Issue published online: 18 FEB 2013
- Article first published online: 21 DEC 2012
- Accepted manuscript online: 20 NOV 2012 03:29AM EST
- Manuscript Accepted: 5 NOV 2012
- Manuscript Revised: 2 NOV 2012
- Manuscript Received: 17 OCT 2012
- USDA/ARS CRIS. Grant Number: 6420-32000-024-00D
- Chryseobacterium indologenes ;
- yellow perch
To identify pathogen of diseased yellow perch and determine their virulence.
Methods and Results
Fifteen Gram-negative bacterial isolates were recovered from the skin lesions of diseased yellow perch (Perca flavescens). Based on API 20NE test, ten isolates were found to share 67·2–99·9% homologies with Chryseobactertium indologenes. Based on fatty acid methyl ester analysis, 13 isolates were found to share similarities with C. indologenes and other species of Chryseobacterium. Based on sequencing results of partial 16S rRNA gene, 13 isolates shared 99% identities (e value = 2e−50) with the 16S rRNA sequence of C. indologenes (GenBank HQ259684). Based on the 16S–23S rRNA intergenic spacer region (ISR) sequence, the 13 isolates shared 88% identity (e value = 1e−165) with the 16S–23S ISR sequence of C. indologenes (GenBank EU014570). T-coffee multiple sequence alignment revealed that the partial 16S rRNA or the 16S–23S ISR sequence of the 13 isolates shared 100% identity with each other. When healthy yellow perch were exposed to the 15 isolates by bath immersion (c. 6 × 107 CFU ml−1 for 1 h), only C. indologenes isolates killed 10–20% of fish, whereas other isolates were avirulent. When yellow perch were exposed to C. indologenes by intraperitoneal injection, mortality was dose dependent, with LD50 and LD95 values of 1·5 × 108 and 3·2 × 108 CFU per fish, respectively.
Chryseobactertium indologenes could be pathogenic to yellow perch.
Significance and Impact of the Study
This is the first report on the isolation of C. indologenes from diseased yellow perch. Virulence studies suggested that C. indologenes could become pathogenic to yellow perch.