Molecular characterization of vibriosis associated bacteria from traditional mud-crab farmed in the North Coast of Central Java, Indonesia

Abstract

This study examines the molecular characterization of bacteria associated with clinical symptoms and the diversity of vibriosis infecting farmed mud crab from three sampling locations, namely Rembang, Demak, and Kendal Districts. The clinical symptom was red-brown spots on carapace and wounds. Twenty-five bacterial isolates were gained from hepatopancreas, gills and carapace of nine infected mud crabs, by culturing in TCBS and TSA medium. Molecular characterization was carried out through modified rep-PCR followed by 16S-rRNA gene amplification. The results indicate that seven out of the 25 isolates, namely CJR14, CJR15, CJD23, CJK10, CJK11, CJD22 and CJR05 were 92-98% firmly related to Vibrio harveyi NCIMB1280, Catenococcus thiocicly TG5-3, Photobacterium ganghwense FR311, Vibrio parahaemolyticus ATCC-1780, Shewanella loihica PV4, Shewanella algae ATCC5, and Vibrio alginolyticus NBRC-15630. This study revealed that the 25 isolates found from infected mud crabs fell into seven groups of bacteria. These seven groups were well-known as pathogens for aquatic organisms. Moreover, according to molecular characterization, the highest diversity of Vibrionaceae was obtained from Rembang, and the bacterium most found in all three sampling sites was C. thiocicly.

Keywords

• mud crab
• 16s rrna
• rep pcr
• vibriosis