Deconstructing the DGAT1 enzyme: membrane interactions at substrate binding sites.
Deconstructing the DGAT1 enzyme: membrane interactions at substrate binding sites.
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DOI：
10.1371/journal.pone.0118407
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Araujo AP
中科院分区：
文献类型：
--
作者：
Lopes JL;Beltramini LM;Wallace BA;Araujo AP
二酰基甘油酰基转移酶1 （DGAT1）是三酰基甘油合成途径中的关键酶。牛DGAT1是一种内质网膜结合蛋白，与牛奶和肉类中脂肪含量的调节有关。本研究的目的是评估DGAT1肽对应于假定的底物结合位点与不同类型模型膜的相互作用。虽然这些肽被预测位于膜结合蛋白的膜外环中，但它们的疏水底物是膜结合分子。在本研究中，在模型膜存在的情况下，检测了参与反应的两种底物结合位点对应的肽，以探测它们之间可能影响底物随后结合的潜在相互作用。虽然其中一种肽的构象在与几种类型的胶束结合时发生了变化，而不管它们的表面电荷如何，这表明它与疏水结构域结合，但另一种肽与带负电荷的模型膜强烈结合。这种结合伴随着构象的改变，并产生脂质体包裹的染料钙黄蛋白的泄漏。观察到的不同疏水和静电相互作用表明，肽可能参与酶与膜表面的相互作用，促进催化组氨酸接近三酰甘油底物。
Diacylglycerol acyltransferase 1 (DGAT1) is a key enzyme in the triacylglyceride synthesis pathway. Bovine DGAT1 is an endoplasmic reticulum membrane-bound protein associated with the regulation of fat content in milk and meat. The aim of this study was to evaluate the interaction of DGAT1 peptides corresponding to putative substrate binding sites with different types of model membranes. Whilst these peptides are predicted to be located in an extramembranous loop of the membrane-bound protein, their hydrophobic substrates are membrane-bound molecules. In this study, peptides corresponding to the binding sites of the two substrates involved in the reaction were examined in the presence of model membranes in order to probe potential interactions between them that might influence the subsequent binding of the substrates. Whilst the conformation of one of the peptides changed upon binding several types of micelles regardless of their surface charge, suggesting binding to hydrophobic domains, the other peptide bound strongly to negatively-charged model membranes. This binding was accompanied by a change in conformation, and produced leakage of the liposome-entrapped dye calcein. The different hydrophobic and electrostatic interactions observed suggest the peptides may be involved in the interactions of the enzyme with membrane surfaces, facilitating access of the catalytic histidine to the triacylglycerol substrates.
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影响因子：
2.9
作者：
DAVISON, SC;WILLS, ED
通讯作者：
WILLS, ED
DOI：
10.1073/pnas.0308518100
发表时间：
2004-02-24
影响因子：
11.1
作者：
Grisart, B;Farnir, F;Georges, M
通讯作者：
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影响因子：
5.8
作者：
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通讯作者：
Tabak, Marcel
影响因子：
4.1
作者：
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通讯作者：
Young, PR
影响因子：
4.8
作者：
McFie, Pamela J.;Stone, Sandra L.;Stone, Scot J.
通讯作者：
Stone, Scot J.