Function of the nonidentical subunits of mammalian pyruvate dehydrogenase.
Function of the nonidentical subunits of mammalian pyruvate dehydrogenase.
复制标题
哺乳动物丙酮酸脱氢酶不同亚基的功能。
DOI：
10.1016/0006-291x(72)90684-5
复制
发表时间：
1972
影响因子：
3.1
通讯作者：
Lester J. Reed
中科院分区：
文献类型：
--
作者：
T. Roche;Lester J. Reed
The pyruvate dehydrogenase (PDH) component of the bovine kidney pyruvate dehydrogenase complex (PDC) contains two nonidentical subunits. PDH catalyzes the decarboxylation of pyruvate to produce α-hydroxyethylthiamine-PP (HETPP) and the reductive acetylation of the lipoyl moieties of dihydrolipoyl transacetylase with HETPP. Phosphorylation of PDH with PDH kinase and ATP markedly inhibits the first reaction but does not inhibit the second reaction. Since the α-subunit but not the β-subunit of PDH undergoes phosphorylation, these results suggest that the α-subunit catalyzes the first reaction and the β-subunit catalyzes the second reaction. Thiamine-PP reduces the rate of phosphorylation of PDC by PDH kinase and ATP. Phosphorylation of PDC increases the KDof the PDC-Mg-thiamine-PP complex about 12-fold. It appears that the thiamine-PP binding site and the phosphorylation site on PDH influence each other and that HETPP is bound to PDH in a different orientation or possibly at a different site than is thiamine-PP.
