[Tetrodotoxin Content of the Small Gastropod Nassarius sufflatus].

Severe tetrodotoxin (TTX) poisoning due to small gastropods has been documented in Japan. In this study, we investigated the TTX content of the muscles and viscera of Nassarius sufflatus collected off the coast of Futaoi Island, Shimonoseki, Yamaguchi Prefecture, Japan, to prevent the occurrence of TTX poisoning caused by this small gastropod. Live specimens were obtained, and their muscles and viscera were collected.

Structural variation of Tn10 that carries tetB found in fish farm bacteria.

Three variants of the composite transposon Tn10 were extracted from transferable plasmids of fish farm bacteria. These variants were identical in insertions with IS10, but differed in another class I transposon insertion and a region of homologous recombination downstream of tetB.

Analysis of a 30 kbp plasmid encoding histidine decarboxylase gene in Tetragenococcus halophilus isolated from fish sauce.

In order to analyze the genes related to the histamine production, a strain of histamine producing halophilic bacteria, referred to as strain H, was isolated using enrichment culture and dilution-to-extinction methods with histidine broth inoculated from the fish sauce mashes. The two Japanese fish sauce mashes used, accumulate over 1000 mg/l of histamine. Phenotypic and 16 S rRNA gene sequence analyses identified strain H as Tetragenococcus halophilus, the predominant histamine producing bacteria present during fish sauce fermentation.

Isolation of multidrug-resistant Stenotrophomonas maltophilia from cultured yellowtail (Seriola quinqueradiata) from a marine fish farm.

Six strains of multidrug-resistant Stenotrophomonas maltophilia were isolated from cultured yellowtail. The strains were divided into two clusters based on the 16S rRNA genes, and all of them contained L1 metallo-beta-lactamase and L2 beta-lactamase genes. Differences in the intercluster divergence between the lactamase genes suggest that horizontal transfer of the genes occurred.

Characterization of group C and G streptococcal strains that cause streptococcal toxic shock syndrome.

Twelve strains (the largest number ever reported) of group C and G(1) streptococci (GCS and GGS, respectively) that caused streptococcal toxic shock syndrome (STSS) were collected and characterized. Eleven strains were identified as Streptococcus dysgalactiae subsp. equisimilis, and one strain was identified as Streptococcus equi subsp.

Similarity of tetracycline resistance genes isolated from fish farm bacteria to those from clinical isolates.

Tetracycline-resistant (Tet(r)) bacteria were isolated from fishes collected at three different fish farms in the southern part of Japan in August and September 2000. Of the 66 Tet(r) gram-negative strains, 29 were identified as carrying tetB only. Four carried tetY, and another four carried tetD.