UV-induced vanadate-dependent modification and cleavage of skeletal myosin subfragment 1 heavy chain. 1. Evidence for active site modification.
UV-induced vanadate-dependent modification and cleavage of skeletal myosin subfragment 1 heavy chain. 1. Evidence for active site modification.
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紫外线诱导的骨骼肌球蛋白亚片段 1 重链的钒酸盐依赖性修饰和裂解。
DOI：
10.1021/bi00422a017
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发表时间：
1988
期刊：
影响因子：
2.9
通讯作者：
Yount,RG
中科院分区：
文献类型：
--
作者：
Grammer,JC;Cremo,CR;Yount,RG
(Si)络合物导致SI的共价修饰，并使捕获的MgADP和VJ迅速释放。这种光修饰的SI的Ca~(2+)-ATPase活性是未辐照的SI的4-5倍，而K+-EDTA-ATPase活性低于对照的10%。Ca~(2+)-ATPase的激活与ADP和VJ的释放均与照射时间呈线性相关。通过用不同的双官能硫醇试剂交联SHI和SH2，对光修饰的SI的硫醇总量以及光修饰的SI对MgADP的捕获能力进行了分析，结果表明，光修饰不涉及这些活性硫醇。Sl-MgADP-VJ络合物辐照后，酶在270 nm处的吸光度显著增加，这与活性部位V的释放有关，表明酶中含有一种芳香族氨基酸(S)。然而，三种不同方法的分析表明色氨酸没有损失。通过用Co2+、Mn2+或Ni2+取代Mg2+，可以防止所有的辐射依赖现象。与以往V；-动力蛋白络合物的辐照研究不同[Lee-Eiford，A.，Ow，R.A.，&Gibbons，I.R.(1986)J.Biol.化学。261,2337-2342]，在光化SI中没有肽键断裂。光修饰的SI能够在与未修饰的SI相似的水平上捕获镁ADP-V。光修饰的Sl-MgADP-V络合物再次从活性中心释放，导致重链断裂，形成NH2末端21 kDa和COOH末端74 kDapepts。所有证据表明，这种新的光修饰和随后的链断裂专门发生在活性部位。
(SI) complex resulted in covalent modification of the SI and in the rapid release of trapped MgADP and Vj. This photomodified SI had Ca2+ ATPase activity 4-5-fold higher than that of the non-irradiated control SI, while the K+ EDTA-ATPase activity was below 10% of controls. There was a linear correlation between the activation of the Ca2+ ATPase and the release of both ADP and Vj with irradiation time. Analysis of the total number of thiols and the ability of photomodified SI to retrap MgADP by cross-linking SHI and SH2 with various bifunctional thiol reagents indicatedthat the photomodification did not involve these reactive thiols. Irradiation of the Sl-MgADP-Vj complex caused a large increase in absorbance of the enzyme at 270 nm which was correlated with the release of V; from the active site, suggesting an aromatic amino acid (s) was (were) involved. However, analysis by three different methods showed no loss of tryptophan. All the irradiation-dependent phenomena could be preventedby replacing Mg2+ with either Co2+, Mn2+, or Ni2+. Unlike previous irradiation studies of V;-dynein complexes [Lee-Eiford, A., Ow, R. A., & Gibbons, I. R.(1986) J. Biol. Chem. 261, 2337-2342], no peptide bonds were cleaved in photomodified SI. Photomodified SI was able to retrap MgADP-V; at levels similar to unmodified SI. Upon irradiation of the photomodified Sl-MgADP-V; complex, MgADP and V; were again released from the active site, resulting in heavy chain cleavage to formNH2-terminal 21-kDa and COOH-terminal 74-kDapeptides. All evidence indicates that this new photomodification and subsequent chain cleavage occur specifically at the active site.
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[12] 用钒酸根离子捕获肌球蛋白活性位点
DOI：
--
发表时间：
1982
期刊：
影响因子：
--
作者：
C. Goodno
通讯作者：
C. Goodno
通过使用硫醇交联试剂捕获金属核苷酸的活性位点对肌球蛋白进行化学修饰。
影响因子：
--
作者：
Wells,JA;Yount,RG
通讯作者：
Yount,RG
N-乙基马来酰亚胺修饰肌球蛋白的酶学特性
DOI：
--
发表时间：
1964
期刊：
影响因子：
--
作者：
T. Sekine;W. W. Kielley
通讯作者：
W. W. Kielley
通过新的硫醇间交联将核苷酸捕获在肌球蛋白亚片段 1 的 ATP 酶位点上。
DOI：
10.1073/pnas.83.7.2037
发表时间：
1986
影响因子：
11.1
作者：
P. Chaussepied;D. Mornet;R. Kassab
通讯作者：
R. Kassab
肌球蛋白两个必需的巯基的空间接近性。
影响因子：
2.9
作者：
E. Reisler;M. Burke;S. Himmelfarb;W. F. Harrington
通讯作者：
W. F. Harrington