title: Isolation and structural determination of the first 8-epi-type tetrodotoxin analogs from the newt, Cynops ensicauda popei, and comparison of tetrodotoxin analogs profiles of this newt and the puffer fish, Fugu poecilonotus.
abstract: Identification of new tetrodotoxin (TTX) analogs from TTX-possessing animals might provide insight into its biosynthesis and metabolism. In this study, four new analogs, 8-epi-5,6,11-trideoxyTTX, 4,9-anhydro-8-epi-5,6,11-trideoxyTTX, 1-hydroxy-8-epi-5,6,11-trideoxyTTX, and 1-hydroxy-4,4a-anhydro-8-epi-5,6,11-trideoxyTTX, were isolated from the newt, Cynops ensicauda popei, and their structures were determined using spectroscopic methods. These are the first 8-epi-type analogs of TTX that have been found in a natural source. Furthermore, we examined the composition of the TTX analogs in this newt and in the ovary of the puffer fish, Fugu poecilonotus, using LC/MS. The results indicate that TTX and 11-deoxyTTX were present in both sources. However, 6-epiTTX and 8-epi-type analogs were detected only in the newt, while 5,6,11-trideoxyTTX was a specific and major analog in the puffer fish. Such considerable differences among analog compositions might reflect differences in the biosynthesis or metabolism of TTX between these animals.
authors.affiliation: Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Kudo
authors.affiliation: Tama Laboratory, Japan Food Research Laboratories, 6-11-10 Nagayama, Tama-shi, Tokyo 206-0025, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yasumoto
authors.affiliation: Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Konoki
authors.affiliation: Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Cho
authors.affiliation: Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Yotsu-Yamashita
mesh_terms: D000818:Animals; D059001:Aquatic Organisms; D002851:Chromatography, High Pressure Liquid; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D012455:Salamandridae / Q000378:metabolism*; D013045:Species Specificity; D016339:Spectrometry, Mass, Fast Atom Bombardment; D023741:Takifugu / Q000378:metabolism*; D013779:Tetrodotoxin / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000737:chemistry*
chemical_list: D007202:Indicators and Reagents; D013779:Tetrodotoxin