The N-Terminus of Human Sulfotransferase 2B1b─a Sterol-Sensing Allosteric Site.
The N-Terminus of Human Sulfotransferase 2B1b─a Sterol-Sensing Allosteric Site.
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DOI：
10.1021/acs.biochem.1c00740
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发表时间：
2022-05-17
期刊：
影响因子：
2.9
通讯作者：
Leyh, Thomas S.
中科院分区：
文献类型：
--
作者：
Cook, Ian;Leyh, Thomas S.
在人类胞质磺基转移酶中，SULT 2B 1b对氧化固醇-氧化胆固醇衍生物具有高度特异性，包括与癌症、动脉粥样硬化以及皮肤和神经退行性疾病有因果关系的核受体配体。信号氧固醇的磺化重定向它们的受体结合功能，并且控制这些功能预计在疾病预防和治疗中证明是有价值的。SULT 2B 1b在人SULT 2同种型中的独特之处在于其长度为18个残基的N-末端，超出家族中第二长的N-末端。在这里，计算机模拟研究用于预测N-末端延伸形成变构口袋并鉴定潜在的变构体。一种这样的变构素，槲皮素，用于确认口袋的存在，并证明变构素结合抑制营业额。口袋的结构是通过定位槲皮素的酶，使用自旋标记三角NMR，然后通过NMR距离约束的分子动力学对接。使用定点诱变和初始速率研究的组合来确认该模型。停流配体结合研究表明，抑制是通过稳定封闭形式的酶活性位点帽，其中封装的核苷酸，减缓其释放。最后，内源性氧化固醇代谢物显示结合的网站在一个高度选择性的方式-两个直接生物合成的前体胆固醇（7-脱氢胆固醇）是一种抑制剂，其他（24-脱氢胆固醇）不是。这些发现提供了对SULT 2B 1b在体内参与的变构对话的深入了解，并建立了开发亚型特异性抑制剂以控制SULT 2B 1b生物学的模板。
Among human cytosolic sulfotransferases, SULT2B1b is highly specific for oxysterols — oxidized cholesterol derivatives, including nuclear-receptor ligands that are causally linked to cancer, atherosclerosis, and skin and neurodegenerative diseases. Sulfonation of signaling oxysterols redirects their receptor-binding functions, and controlling these functions is expected to prove valuable in disease prevention and treatment. SULT2B1b is distinct among the human SULT2 isoforms by virtue of its atypically long N-terminus, which extends 18-residues beyond the next longest N-terminus in the family. Here, in-silico studies are used to predict that the N-terminal extension forms an allosteric pocket and to identify potential allosteres. One such allostere, quercetin, is used to confirm the existence of the pocket and to demonstrate that allostere binding inhibits turnover. The structure of the pocket is obtained by positioning quercetin on the enzyme, using spin-label-triangulation NMR, followed by NMR-distance constrained molecular dynamics docking. The model is confirmed using a combination of site-directed mutagenesis and initial-rate studies. Stopped-flow ligand-binding studies demonstrate that inhibition is achieved by stabilizing the closed form of the enzyme active-site cap, which encapsulates the nucleotide, slowing its release. Finally, endogenous oxysterol metabolites are shown bind the site in a highly selective fashion — one of two immediate biosynthetic precursors of cholesterol (7-dehydrocholesterol) is an inhibitor, the other (24-dehydrocholesterol) is not. These findings provide insight into the allosteric dialogue in which SULT2B1b participates in in vivo, and establishes a template against which to develop isoform-specific inhibitors to control SULT2B1b biology.
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DOI：
10.1074/jbc.ra120.015177
发表时间：
2021-01
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Cook I;Cacace M;Wang T;Darrah K;Deiters A;Leyh TS
通讯作者：
Leyh TS
影响因子：
48
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影响因子：
4.8
作者：
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通讯作者：
Wennmalm, A
影响因子：
4.8
作者：
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通讯作者：
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DOI：
10.1073/pnas.1613913113
发表时间：
2016-12-13
影响因子：
11.1
作者：
Cook, Ian;Wang, Ting;Leyh, Thomas S.
通讯作者：
Leyh, Thomas S.