Toxin-screening and identification of bacteria isolated from highly toxic marine gastropod Nassarius semiplicatus.
Bacteria isolated from a highly toxic sample of gastropod Nassarius semiplicatus in Lianyungang, Jiangsu Province in July 2007, were studied to probe into the relationship between bacteria and toxicity of nassariid gastropod. The toxicity of the gastropod sample was 2 x 10(2)mouse unit (MU) per gram of tissue (wet weight). High concentration of tetrodotoxin (TTX) and its analogues (TTXs) were found in the digestive gland and muscle of the gastropod, using high performance liquid chromatography coupled with mass chromatography (LC-MS). Bacterial strains isolated from the digestive gland were cultured and screened for TTX with a competitive ELISA method. Tetrodotoxin was detected in a proportion of bacterial strains, but the toxin content was low. Partial 16S ribosomal DNA (rDNA) of the TTX-producing strains was then sequenced and compared with those published in the GenBank to tentatively identify the toxic strains. It was found that most of the toxic strains were closely affiliated with genus Vibrio, and the others were related to genus Shewanella, Marinomonas, Tenacibaculum and Aeromonas. These findings suggest that tetrodotoxin-producing bacteria might play an important role in tetrodotoxin accumulation/production in N. semiplicatus.
Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
Xiao-Jie
XJ
Wang
Ren-Cheng
RC
Yu
Xuan
X
Luo
Ming-Jiang
MJ
Zhou
Xiang-Tian
XT
Lin
D000818:Animals; D001419:Bacteria / Q000302:isolation & purification* / Q000472:pathogenicity; D002851:Chromatography, High Pressure Liquid; D049851:Gastropoda / Q000382:microbiology* / Q000472:pathogenicity*; D013058:Mass Spectrometry; D051379:Mice; D013779:Tetrodotoxin / Q000032:analysis* / Q000096:biosynthesis / Q000633:toxicity
D013779:Tetrodotoxin