26109-32-0

Upstream product

• 150-97-0 D,L-mevalonic acid 
• 21435-01-8 7β-hydroxy-(-)-kaur-16-en-19-oic acid 
• 55093-61-3 C₂₃H₃₄O₄ 

Relevant academic research and scientific papers

Influence of electron transport proteins on the reactions catalyzed by Fusarium fujikuroi gibberellin monooxygenases

The multifunctional cytochrome P450 monooxygenases P450-1 and P450-2 from Fusarium fujikuroi catalyze the formation of GA14 and GA4, respectively, in the gibberellin (GA)-biosynthetic pathway. However, the activity of these enzymes is qualitatively and quantitatively different in mutants lacking the NADPH:cytochrome P450 oxidoreductase (CPR) compared to CPR-containing strains. 3β-Hydroxylation, a major P450-1 activity in wild-type strains, was strongly decreased in the mutants relative to oxidation at C-6 and C-7, while synthesis of C19-GAs as a result of oxidative cleavage of C-20 by P450-2 was almost absent whereas the C-20 alcohol, aldehyde and carboxylic acid derivatives accumulated. Interaction of the monooxygenases with alternative electron transport proteins could account for these different product distributions. In the absence of CPR, P450-1 activities were NADH-dependent, and stimulated by cytochrome b5 or by added FAD. These properties as well as the decreased efficiency of P450-1 and P450-2 in the mutants are consistent with the participation of cytochrome b5:NADH cytochrome b5 reductase as redox partner of the gibberellin monooxygenases in the absence of CPR. We provide evidence, from either incubations of GA12 (C-20 methyl) with cultures of the mutant suspended in [18O]H2O or maintained under an atmosphere of [18O]O2:N2 (20:80), that GA15 (C-20 alcohol) and GA24 (C-20 aldehyde) are formed directly from dioxygen and not from hydrolysis of covalently enzyme-bound intermediates. Thus these partially oxidized GAs correspond to intermediates of the sequential oxidation of C-20 catalyzed by P450-2.

BIOSYNTHESIS OF GIBBERELLIN A12-ALDEHYDE, GIBBERELLIN A12 AND THEIR KAURENOID PRECURSORS FROM MEVALONIC ACID IN A CELL-FREE SYSTEM FROM IMMATURE SEED OF PHASEOLUS COCCINEUS

A cell-free system capable of gibberellin (GA) biosynthesis has been prepared from immature seed of Phaseolus coccineus.This system converted mevalonic acid (MVA) to ent-kaurene, ent-kaurenoic acid, ent-kauradienoic acid, ent-7α-hydroxykaurenoic acid, ent-6α,7α-dihydroxykaurenoic acid, GA12-aldehyde and GA12. ent-Kaurene was converted to ent-kaurenol, ent-kaurenal, ent-kaurenoic acid and ent-7α-hydroxykaurenoic acid.All identifications were by GC/MC.The pathway from MVA to GA12-aldehyde in this species thus appears to be the same as that found in cell-free preparations derived from immature seed of other species.Key Word Index-Phaseolus coccineus; Leguminosae; runner bean; seed development; biosynthesis; cell-free system; HPLC; GC/MC; gibberellin.