âThatâs something we can test. If it does, caspase-1 inhibitors mightâand I emphasize mightâbecome a component of a curative cocktail.â G. Doitsh et al., âCell death by pyroptosis drives CD4 T-cell depletion in HIV-1 infection,â Nature, doi:10.1038/nature12940, 2013.
Decades ago it was believed that a cascade of enzymes controls the activity of HMG-CoA reductase: an HMG-CoA reductase kinase was thought to inactivate the enzyme, and the kinase in turn was held to be activated via phosphorylation by HMG-CoA reductase kinase kinase.
This step is a direct nucleophilic attack of the hydroxyl group on the terminal phosphoryl group of the ATP molecule (Aleshin, 99). This produces glucose-6-phosphate and ADP. Hexokinase is the enzyme that catalyzes this phosphoryl-group-transfer.exokinase undergoes and induced-fit conformational change when it binds to glucose, which ultimately prevents the hydrolysis of ATP. It is also allosterically inhibited by physiological concentrations of its immediate product, glucose-6-phosphate.