TY - JOUR
T1 - Identification of a novel saxitoxin analogue, 12β-deoxygonyautoxin 3, in the cyanobacterium, anabaena circinalis (TA04)
AU - Minowa, Takashi
AU - Cho, Yuko
AU - Oshima, Yasukatsu
AU - Konoki, Keiichi
AU - Yotsu-Yamashita, Mari
N1 - Funding Information:
Funding: This work was funded by the Japan Society for the Promotion of Science (JSPS) through its KAKENHI Grant-in-Aid for Scientific Research no. JP17H03809 to M.Y.-Y. and JP19K06232 to Y.C., and by an Innovative Area, Frontier Research on Chemical Communications grant (no. JP17H06406) and on Redesigning Biosynthetic Machineries (no. JP19H04636), and Grant-in-Aid for Challenging Exploratory Research (no. JP19K22266) to M.Y.-Y.
Publisher Copyright:
© 2019 by the authors.
PY - 2019/9/16
Y1 - 2019/9/16
N2 - Saxitoxin (STX) and its analogues, the potent voltage-gated sodium channel blockers, are biosynthesized by freshwater cyanobacteria and marine dinoflagellates. We previously identified several biosynthetic intermediates in the extract of the cyanobacterium, Anabaena circinalis (TA04), that are primarily produced during the early and middle stages in the biosynthetic pathway to produce STX. These findings allowed us to propose a putative biosynthetic pathway responsible for STX production based on the structures of these intermediates. In the present study, we identified 12β-deoxygonyautoxin 3 (12β-deoxyGTX3), a novel STX analogue produced by A. circinalis (TA04), by comparing the retention time and MS/MS fragmentation pattern with those of synthetic standards using LC-MS. The presence of this compound in A. circinalis (TA04) is consistent with stereoselective enzymatic oxidations at C11 and C12, and 11-O-sulfation, during the late stage of STX biosynthesis, as proposed in previous studies.
AB - Saxitoxin (STX) and its analogues, the potent voltage-gated sodium channel blockers, are biosynthesized by freshwater cyanobacteria and marine dinoflagellates. We previously identified several biosynthetic intermediates in the extract of the cyanobacterium, Anabaena circinalis (TA04), that are primarily produced during the early and middle stages in the biosynthetic pathway to produce STX. These findings allowed us to propose a putative biosynthetic pathway responsible for STX production based on the structures of these intermediates. In the present study, we identified 12β-deoxygonyautoxin 3 (12β-deoxyGTX3), a novel STX analogue produced by A. circinalis (TA04), by comparing the retention time and MS/MS fragmentation pattern with those of synthetic standards using LC-MS. The presence of this compound in A. circinalis (TA04) is consistent with stereoselective enzymatic oxidations at C11 and C12, and 11-O-sulfation, during the late stage of STX biosynthesis, as proposed in previous studies.
KW - Anabaena circinalis
KW - Biosynthesis
KW - Gonyautoxin
KW - Paralytic shellfish toxins
KW - Saxitoxin
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U2 - 10.3390/toxins11090539
DO - 10.3390/toxins11090539
M3 - Article
C2 - 31527551
AN - SCOPUS:85072285370
VL - 11
JO - Toxins
JF - Toxins
SN - 2072-6651
IS - 9
M1 - toxins11090539
ER -