Sulfhydryl groups, regulated

Dinkova-Kostova AT, Holtzclaw WD, Cole RN, Itoh K, Wakabayashi N, Katoh Y, Yamamoto M, Talalay P. 2002. Direct evidence that sulfhydryl groups of Keapl are the sensors regulating induction of phase 2 enzymes that protect against carcinogens and oxidants. Proc Natl Acad Sci USA 99 11908-11913. 

GSH is involved in the regulation (glutathionylation) of action of several key-enzymes and other proteins (e.g., phosphorylase, creatinine kinase, ras) and in the restoration of the sulfhydryl groups of proteins (maintenance of enzymes and proteins in active form) ... 

Posttranslational regulation of glutamate transporters includes changes in cell surface expression due to trafficking between the plasma membrane and intracellular compartments, and modulation of transport activity by direct phosphorylation, redox modulation of sulfhydryl groups and inhibition by arachidonic acid and other ci5-polyunsaturated fatty acids. 

D-Fructose 1,6-diphosphatase is a regulatory enzyme playing a key role in the control of gluconeogenesis. A number of mechanisms have been proposed for the regulation of D-fructose 1,6-diphosphatase activity, including allosteric control by AMP,396 inhibition by D-fructose 1,6-bisphosphate, ADP, or ATP, and modification of the sulfhydryl groups of the enzyme.397,398... 

Regulation of liver D-fructose 1,6-diphosphatase could involve modification of the sulfhydryl group of the enzyme.397 Cystamine (2,2 -dithiobisethylamine) or homocysteine undergoes a disulfide exchange-reaction with two reactive cysteine residues. This exchange leads to a four-fold increase in catalytic activity.405 Other sulfhydryl reagents, such as l-fluoro-2,4-dinitrobenzene (FDNB), p-mercuri-benzoate (PMB), and 2-iodoacetamide, also activate liver D-fructose... 

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