Adenylate Kinase-Catalyzed Reaction of AMP in Pieces: Enzyme Activation for Phosphoryl Transfer to Phosphite Dianion.
Adenylate Kinase-Catalyzed Reaction of AMP in Pieces: Enzyme Activation for Phosphoryl Transfer to Phosphite Dianion.
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AMP在碎片中的腺苷酸激酶催化反应：磷酸化转移至磷酸二角体的酶激活。
DOI：
10.1021/acs.biochem.1c00535
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发表时间：
2021-09-07
期刊：
影响因子：
2.9
通讯作者：
Richard JP
中科院分区：
文献类型：
--
作者：
Fernandez PL;Richard JP
腺苷5 '-三磷酸（ATP）和腺苷5'-单磷酸（AMP）与腺苷酸激酶（AdK）的结合驱动底物腺苷基团上的盖的闭合。我们测试的假设，这种构象变化激活AdK催化。人类腺苷酸激酶1（HsAdK 1）催化的磷酰基转移到AMP的速率常数kcat/Km = 7.0 x 106 M−1 s−1，亚磷酸根二价阴离子（kHPi）obs ≤ 1 x 10−4 M−1 s−1，表明腺苷酸基团的结合能使磷酰基从ATP转移的速率加速≥7.0 x 1010倍。测定了1-（β-d-赤呋喃糖基）腺嘌呤（EA）活化的磷酰基转移到亚磷酸根二价阴离子的三级速率常数kcat/KHPiKEA = 260 M−2 s−1，并通过31 P NMR表征了异次磷酸反应产物。结果表明：（i）AMP的腺苷基团导致的磷酰基转移的过渡态稳定性≥14.7 kcal/mol，EA驱动的构象变化导致的速率加速≥2.6 x 106倍，以及（ii）EA激活的磷酰基从ATP转移至亚磷酸酯的过渡态稳定性恢复≥8.7 kcal/mol。
The binding of adenosine 5’-triphosphate (ATP) and adenosine 5’-monophosphate (AMP) to adenylate kinase (AdK) drives closure of lids over the substrate adenosyl groups. We test the hypothesis that this conformational change activates AdK for catalysis. The rate constants for Homo sapiens adenylate kinase 1 (HsAdK1)-catalyzed phosphoryl group transfer to AMP, kcat/Km = 7.0 x 106 M−1 s−1, and phosphite dianion, (kHPi)obs ≤ 1 x 10−4 M−1 s−1, show that the binding energy of the adenosyl group effects a ≥7.0 x 1010-fold rate acceleration of phosphoryl transfer from ATP. The third-order rate constant of kcat/KHPiKEA = 260 M−2 s−1 for 1-(β-d-erythrofuranosyl)adenine (EA)-activated phosphoryl transfer to phosphite dianion was determined, and the isohypophosphate reaction product characterized by 31P NMR. The results demonstrate: (i) a ≥14.7 kcal/mol stabilization of the transition state for phosphoryl transfer by the adenosyl group of AMP and a ≥2.6 x 106-fold rate acceleration from the EA-driven conformational change, and (ii) the recovery of ≥8.7 kcal/mol of this transition state stabilization for EA-activated phosphoryl transfer from ATP to phosphite.
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影响因子：
18.3
作者：
Richard JP;Amyes TL;Reyes AC
通讯作者：
Reyes AC
影响因子：
8
作者：
Bellinzoni, Marco;Haouz, Ahmed;Alzari, Pedro M.
通讯作者：
Alzari, Pedro M.
影响因子：
4.6
作者：
CARROLL, RL;MESMER, RE
通讯作者：
MESMER, RE
用于酶催化的质子转移，氢化物转移和脱羧的活化氧结合结构域：特异性和酶结构。
影响因子：
15
作者：
Reyes, Archie C.;Zhai, Xiang;Morgan, Kelsey T.;Reinhardt, Christopher J.;Amyes, Tina L.;Richard, John P.
通讯作者：
Richard, John P.
影响因子：
2.9
作者：
ALBERY, WJ;KNOWLES, JR
通讯作者：
KNOWLES, JR