Howland J L, Osrin D, Donatelli M, Theofrastous J P
Biochim Biophys Acta. 1984 Dec 19;778(3):400-4. doi: 10.1016/0005-2736(84)90386-9.
Erythrocyte ghost NADH dehydrogenase is inhibited in a competitive fashion by ATP and ADP whereas other nucleoside di- and triphosphates, cyclic nucleosides, as well as non-phosphorylating ATP analogs are relatively ineffective. In addition, this enzyme, measured with ferricyanide as electron acceptor, is inhibited by uncouplers of oxidative phosphorylation (proton-conducting reagents), the inhibition being competitive in character (i.e., the uncouplers were without influence upon maximum velocity). The effectiveness of the uncouplers was in the order of their hydrophobic character with the presence of the alkyl side chain rendering nonyl-dinitrophenol much more active than 2,6-dinitrophenol itself. Hydrophobic compounds that are not protonophores (e.g., eosin, proflavin or valinomycin) were not inhibitory. Whereas adenine nucleotides probably inhibit NADH oxidation competitively through structural similarity with the substrate, it appears unlikely that uncouplers compete at the NADH site directly. Rather, the apparently-competitive inhibition in the latter case may reflect competition for proton transfer to an acceptor residing in a hydrophobic region of the enzyme complex.
红细胞血影NADH脱氢酶受到ATP和ADP的竞争性抑制，而其他核苷二磷酸和三磷酸、环核苷以及非磷酸化ATP类似物的抑制作用相对较弱。此外，以铁氰化物作为电子受体测定的这种酶，受到氧化磷酸化解偶联剂（质子传导试剂）的抑制，这种抑制具有竞争性（即解偶联剂对最大反应速度没有影响）。解偶联剂的有效性与其疏水特性有关，烷基侧链的存在使壬基二硝基苯酚比2,6-二硝基苯酚本身活性高得多。不是质子载体的疏水化合物（如伊红、黄素或缬氨霉素）没有抑制作用。腺嘌呤核苷酸可能通过与底物结构相似而竞争性抑制NADH氧化，而后一种情况下解偶联剂不太可能直接在NADH位点竞争。相反，后一种情况下明显的竞争性抑制可能反映了对质子转移到位于酶复合物疏水区域的受体的竞争。
