EC Number   |
Substrates |
Organism |
Products |
Reversibility |
|---|
    2.5.1.21 | more |
no substrate: 6,7-dihydrofarnesyl diphosphate, 3-desmethylfarnesyl diphosphate |
Saccharomyces cerevisiae |
? |
- |
? |
| 2.5.1.21 | more |
not metabolized: (E)-6,7,10,11-tetrahydrofarnesyl diphosphate |
Saccharomyces cerevisiae |
? |
- |
? |
| 2.5.1.21 | more |
enzyme is key regulator not only for phytosterol but also for triterpene biosynthesis |
Panax ginseng |
? |
- |
? |
| 2.5.1.21 | more |
the catalytic process involves two reactions: firstly, two FPP molecules are condensed to form presqualene diphosphate (PSPP), an intermediate with a cyclopropane C1'-C2-C3 ring structure, and secondly, PSPP undergoes a NADPH-dependent rearrangement and reduction to generate the end product squalene |
Homo sapiens |
? |
- |
? |
| 2.5.1.21 | more |
catalytic mechanism, overview |
Homo sapiens |
? |
- |
? |
| 2.5.1.21 | more |
squalene and botryococcene are branched-chain, triterpene compounds that arise from the head-to-head condensation of two molecules of farnesyl diphosphate to yield 1'-1 and 1'-3 linkages, respectively. Different enzymes are responsible for botryococcene and squalene biosynthesis in the green alga Botryococcus braunii race B. The specificity for the 1'-1 and 1'-3 linkages is controlled by residues in the active sites that can mediate catalytic specificity. Identification of several amino acid positions contributing to the rearrangement of the cyclopropyl intermediate to squalene, The same positions do not appear to be sufficient to account for the cyclopropyl rearrangement to give botryococcene, oerview |
Botryococcus braunii |
? |
- |
? |
| 2.5.1.21 | more |
analysis of substrate specificity, overview |
Botryococcus braunii |
? |
- |
? |
| 2.5.1.21 | presqualene diphosphate + NAD(P)H |
- |
Rattus norvegicus |
squalene + NAD(P)+ + diphosphate |
- |
? |
| 2.5.1.21 | presqualene diphosphate + NAD(P)H |
- |
Saccharomyces cerevisiae |
squalene + NAD(P)+ + diphosphate |
- |
? |
| 2.5.1.21 | presqualene diphosphate + NAD(P)H |
in presence of reducing pyridine nucleotide, preferably NADPH, squalene is formed, in absence of reducing cofactor the rate of the condensation reaction is lower and all of the product accumulates as presqualene diphosphate |
Rattus norvegicus |
squalene + NAD(P)+ + diphosphate |
- |
? |
