Isolation of a Lysinibacillus fusiformis strain with tetrodotoxin-producing ability from puffer fish Fugu obscurus and the characterization of this strain

Six dominant strains were isolated from the livers of the puffer fish Fugu obscurus and were screened for their TTX production-ability. Electrospray ionization-mass spectrometry (ESI-MS) analyses revealed that strain B-1 produced TTX and related substances; mouse bioassay revealed that 23.9 mouse units (MU) of toxins were present in 200 ml of broth medium. On the basis of the physiological and biochemical characteristics of this strain and the results of 16S rRNA analysis, strain B-1 was identified as Lysinibacillus fusiformis.