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Enzymatic one-step ring contraction for quinolone biosynthesis.

ABSTRACT: The 6,6-quinolone scaffolds on which viridicatin-type fungal alkaloids are built are frequently found in metabolites that display useful biological activities. Here we report in vitro and computational analyses leading to the discovery of a hemocyanin-like protein AsqI from the Aspergillus nidulans aspoquinolone biosynthetic pathway that forms viridicatins via a conversion of the cyclopenin-type 6,7-bicyclic system into the viridicatin-type 6,6-bicyclic core through elimination of carbon dioxide and methylamine through methyl isocyanate.

SUBMITTER: Kishimoto S

PROVIDER: S-EPMC6053404 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Enzymatic one-step ring contraction for quinolone biosynthesis.

Kishimoto Shinji S Hara Kodai K Hashimoto Hiroshi H Hirayama Yuichiro Y Champagne Pier Alexandre PA Houk Kendall N KN Tang Yi Y Watanabe Kenji K

Nature communications 20180719 1

The 6,6-quinolone scaffolds on which viridicatin-type fungal alkaloids are built are frequently found in metabolites that display useful biological activities. Here we report in vitro and computational analyses leading to the discovery of a hemocyanin-like protein AsqI from the Aspergillus nidulans aspoquinolone biosynthetic pathway that forms viridicatins via a conversion of the cyclopenin-type 6,7-bicyclic system into the viridicatin-type 6,6-bicyclic core through elimination of carbon dioxide ...[more]

PMID: 30026518

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