Inhibition dehydrogenase

At concentrations having little effect on viability, glutaraldehyde inhibits dehydrogenase activity [121]. Various concentrations inhibit several periplasmic enzymes, including APase [175]. Studies on the interaction of a... 

Crotonoside. Crotonoside, also caHed isoguanosine, (45) has been isolated from Croton tiglium (4). Ip administration of [2- C]crotonoside to rats results in incorporation into nucleic acids (qv). It inhibits the inducible binding sites, inhibits glutamic acid dehydrogenase, and accumulates cAMP. 

Although the stmctures of ribavirin and selenazofutin are similar, they appear to exert their antiviral action at different enzyme sites along the same biochemical pathway. Selenazofutin forms the nicotinamide adenosiae dinucleotide (NAD) analogue, which inhibits IMP dehydrogenase by binding ia place of the NAD cofactor, and hence this potent reduction of guanylate pools is responsible for the antiviral effect of selenazofutin. 

Succinate Dehydrogenase—A Classic Example of Competitive Inhibition... 

The enzyme succinate dehydrogenase (SDH) is competitively inhibited by malo-nate. Figure 14.14 shows the structures of succinate and malonate. The structural similarity between them is obvious and is the basis of malonate s ability to mimic succinate and bind at the active site of SDH. However, unlike succinate, which is oxidized by SDH to form fumarate, malonate cannot lose two hydrogens consequently, it is unreactive. 

Acetyl-CoA is a potent allosteric effector of glycolysis and gluconeogenesis. It allosterically inhibits pyruvate kinase (as noted in Chapter 19) and activates pyruvate carboxylase. Because it also allosterically inhibits pyruvate dehydrogenase (the enzymatic link between glycolysis and the TCA cycle), the cellular fate of pyruvate is strongly dependent on acetyl-CoA levels. A rise in... 

A Metabolite of Hypoglycin from Akee Fruit Inhibits Acyl-CoA Dehydrogenase... 

FIGURE 24.14 The conversion of hypoglycin from akee fruit to a form that inhibits acyl-CoA dehydrogenase. 

Tolf and eolleagues prepared 4-alkynylpyrazoles and their saturated analogs and assayed them for in vitro inhibition of horse liver aleohol dehydrogenase (LADH). It was shown that the saturated substituents displayed inereased inhibitory aetivity (84BAP265). 

Ethanol is almost entirely metabolized in the liver. The first step, oxidation by alcohol dehydrogenase, yields acetaldehyde, a reactive and toxic compound. Essentially all of the acetaldehyde is converted to acetate by the liver enzyme aldehyde dehydrogenase. Aldehyde dehydrogenase is inhibited by the drag disulfiram. Given alone, disulfiram is a nontoxic substance. However, ethanol consumption in the presence of... 

The active metabolite of leflunomide, the ring-opened drug A771726, inhibits dihydroorotate dehydrogenase (DHOD) which is the key enzyme of the de novo pyrimidine synthesis. Inhibition of synthesis stops proliferation of activated lymphocytes. The leflunomide derivative FK778 which shows similar therapeutic efficacy but shorter half-life is investigated in clinical trials. 

---