Sarjito Sarjito, Alfabetian Harjuno Condro Haditomo, Slamet Budi Prayitno, Aninditia Sabdaningsih, Desrina, and Restiana Wisnu Ariyati

DOI: 10.14456/sjst-psu.2022.126

pp. 945 - 952

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.