Trans-enoyl reductase; part of the gene cluster that mediates the biosynthesis of myceliothermophins, mycotoxins that contain a trans-fused decalin ring system connected to a conjugated 3-pyrrolin-2-one moiety and that have potential anti-tumor properties (PubMed:27960349). The polyketide synthase module (PKS) of the PKS-NRPS mycA is responsible for the synthesis of the octaketide backbone (PubMed:27960349). The downstream nonribosomal peptide synthetase (NRPS) module then amidates the carboxyl end of the octaketide with a leucine (PubMed:27960349). A reductase-like domain (R) at the C-terminus catalyzes the reductive release of the polyketide-amino acid intermediate (PubMed:27960349). Because mycA lacks a designated enoylreductase (ER) domain, the required activity is provided the enoyl reductase mycC (PubMed:27960349). Following mycA-catalyzed construction and release of aminoacyl polyketide aldehyde, Knoevenagel condensation yields the expected ketone (PubMed:27960349). This C18 keto acyclic precursor is the substrate of the Diels-Alderase mycB, that catalyzes the Diels-Alder cycloaddition to produce myceliothermophin E (PubMed:27960349). A yet unknown oxygenase involved in the production of myceliothermophin A, via substitution with a hydroxyl group at the C21, has still to be identified (PubMed:27960349). ATP + 12 H(+) + L-leucine + 8 malonyl-CoA + 9 NADPH + 4 S-adenosyl-L-methionine = (5S)-5-(2-methylpropyl)-3-[(2E,6R,8E,10E,12E)-6,8,10,12-tetramethyltetradeca-2,8,10,12-tetraenoyl]-2,5-dihydro-1H-pyrrol-2-one + AMP + 8 CO2 + 8 CoA + diphosphate + 7 H2O + 9 NADP(+) + 4 S-adenosyl-L-homocysteine Mycotoxin biosynthesis. Monomer. Belongs to the zinc-containing alcohol dehydrogenase family.