EC Number   |
Reaction |
Reference  |
|---|
   4.1.99.16 | (1E,4S,5E,7R)-germacra-1(10),5-dien-11-ol + H2O = (-)-geosmin + acetone |
- |
- |
| 4.1.99.16 | (1E,4S,5E,7R)-germacra-1(10),5-dien-11-ol + H2O = (-)-geosmin + acetone |
conversion of germacradienol to geosmin results in the release of the three-carbon side chain as acetone and involves a 1,2-hydride shift of the bridgehead hydrogen exclusively into ring B of geosmin |
692761 |
| 4.1.99.16 | (1E,4S,5E,7R)-germacra-1(10),5-dien-11-ol + H2O = (-)-geosmin + acetone |
the active site in the N-terminal domain of enzyme ScGS catalyzes the ionization-dependent cyclization of FPP to form diphosphate and two cyclic products: germacradienol (major product, 85%) and germacrene D (minor product, 15%). After dissociation from the N-terminal domain, germacradienol is rebound to the active site of the C-terminal domain where it is converted to geosmin in a protonation-dependent cyclization reaction accompanied by the elimination of acetone through a retro-Prins reaction. The tandem cyclization-fragmentation reactions catalyzed by ScGS require two distinct active sites, a unique alphaalpha domain architecture is predicted for ScGS based on primary structure analysis |
-, 747096 |
