Tetrodotoxin-Producing Bacteria from the Horseshoe Crab Carcinoscorpius rotundicauda

Abstract

Attempts were made to detect tetrodotoxin (TTX)-producing bacteria in the Thai horseshoe crab Carcinoscorpius rotundicauda, one of TTX-containing marine invertebrates. Thirteen dominant bacteria were isolated from the intestinal contents of live horseshoe crab specimens, and were cultured in a 2 × ORI medium at 20°C for 24 h. Bacterial cells of each strain were harvested, ultrasonicated and ultrafiltered, and TTX and anh-TTX fractions were separated from the filtrate by Bio-Gel P-2 column chromatography. HPLC, UV and GC-MS analyses showed that all out of the 13 strains isolated produced anh-TTX, and one strain produced TTX and anh-TTX. The strain which produced both toxins was identified as Vibrio alginolyticus on the basis of biochemical and other characters. © 1988, The Japanese Society of Fisheries Science. All rights reserved.