Starch Synthesis | Metabolism | Metabolic Pathway
13/03/1995 · In a metabolic pathway, ..
and all other nematodes studied to date lack the capacity to synthesize sterols from acetate (; ). This requirement can be met by providing exogenous cholesterol, -sitosterol, 7-dehydrocholesterol, ergosterol, or stigmasterol (; ). Indeed, can use various dietary sterols, including plant sterols (). and species have the capacity to synthesize lanosterol from squalene 2,3-oxide; the major metabolic block in the pathway of sterol biosynthesis likely occurs between farnesol (and any other steps before farnesol) and squalene (; ). More recently, ) constructed a strain expressing human dehydrocholesterol reductase, which enabled the worms to convert exogenous 7-dehydrocholesterol into cholesterol. This transgenic strain was slightly longer-lived and stress-resistant, but showed reduced fecundity.
become the substrate for the next enzyme in a metabolic pathway
This allows for additional control by the cell to switch between biosynthesis of new macromolecules and the energy requirements to fuel those biosynthetic pathways, and also allows differences in metabolism and control of metabolism from cell type to cell type, or species to species.