The biosynthesis of the tryptophan-derived mould metabolites roquefortine and aszonalenin

Abstract

~-[2,4,5,6,7-2H~lTryptophan has been incorporated into roquefortine and aszonalenin, by Penicillium roqueforti and by Aspergillus zonatus respectively, with retention of five deuterium atoms; the 5a-hydrogen of each of these metabolites is derived from the 2-hydrogen of tryptophan, contrary to an earlier report.A considerable degree of interest has been shown during the last two decades in the biosynthesis of tryptophan-derived metabolites that contain a 1 ,l-dimethylallyl substituent.1.2 In this connection Barrow et al. have reported that isotopic label from [2,4,5,6,7-2H5]tryptophan was incorporated by a trypto-

Reverse Prenyltransferase in the Biosynthesis of Fumigaclavine C in Aspergillus fumigatus: Gene Expression, Purification, and Characterization of Fumigaclavine C Synthase FGAPT1

“…190 12. Our results therefore support the current hypothesis for the mechanism of this reverse prenylation, as discussed by Williams et al14 Feeding experiments on echinulin,40 roquefortine,41, 42 paraherquamide A,15, 43 brevianamide A,15 and austamide15 also indicated that the reverse prenylation is more likely to take place by a simple S N 2′ alkylation.…”

Acetylaszonalenin Biosynthesis in Neosartorya fischeri

“…According to this hypothesis, H-2 of L-tryptophan would be retained in roquefortine or aszonalenin. This hypothesis was supported by the observation that feeding of L-[2,4,5,6,7-2 H 5 ]tryptophan in P. roqueforti and A. zonatus resulted in formation of roquefortine and aszonalenin with significant incorporation of deuterium at all of the five positions (20,21). This indicated that the H-2 was retained during the prenylation reaction.…”

“…Feeding experiments have shown that L-tryptophan was incorporated into aszonalenin (20,21), indicating that the original (S) configuration of the ␣-atom in L-tryptophan was converted to (R) configuration at position C11 of aszonalenin. Prenylation and acetylation steps led to formation of aszonalenin and acetylaszonalenin with the same configuration at C11 as in (R)-benzodiazepinedione or D-tryptophan.…”

“…Investigation on the biosynthesis of these compounds was limited to precursor feeding experiments in P. roqueforti for roquefortine and in A. zonatus for acetylaszonalenin (1,20,21). It could be demonstrated that tryptophan was the biosynthetic precursor in the biosynthesis of both compounds (20,21).…”

Penicillium roqueforti : a multifunctional cell factory of high value-added molecules

“…The alkaloid roquefortine D (5) was subsequently isolated-it was suggested that its biogenesis passes through mevalonic acid, tryptophan and histidine (Ohmomo et al 1978). More recently, some evidence supporting this hypothesis has been provided (Bhat et al 1993). Moreover, Bellinck (1975) studied the chemistry of the pigments of P. roqueforti and showed that these compounds are polyphenolic in nature (Fig.…”