Role of individual positive charges in the membrane orientation and activity of transporters of the small multidrug resistance family.
Role of individual positive charges in the membrane orientation and activity of transporters of the small multidrug resistance family.
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单个正电荷在小型多药耐药家族转运蛋白的膜取向和活性中的作用。
DOI：
10.1021/bi300854c
复制
发表时间：
2012
期刊：
影响因子：
2.9
通讯作者：
J. Lolkema
中科院分区：
文献类型：
--
作者：
Magdalena Kolbusz;D. Slotboom;J. Lolkema
单个带正电荷的残基在膜上的取向的影响进行了分析，在三个双拓扑结构的转运蛋白的小的多药耐药（SMR）家庭：AAVE 4701 aave的燕麦，EMREecol的大肠杆菌，和RRUA 0272 rrub的红杜鹃。结果表明，（i）单个正电荷对方向有不同的影响，（ii）在三种不同蛋白质中保守的正电荷对方向没有相同的影响，（iii）奇数和偶数环中的正电荷有不同的影响，（iv）对于一些，但不是全部，影响取决于其他正电荷的存在，和（v）在某些情况下去除了所有正电荷的蛋白质是双拓扑结构蛋白质，而在其它情况下具有单一取向。在后一种蛋白质的环中放置少量的正电荷导致违反先前报道的所谓的正内部规则[Kolbusz，M.一、等人（2010）J. Mol. 402，127-138]。我们的结论是，每个正电荷的两个方向之间的分布向状态，在细胞质中的正电荷，但正电荷以外的内在因素确定的方向以及移动。AAVE 4701 aave和EMREecol的突变体赋予对溴化乙锭的抗性的能力揭示了在第二环中保守的正电荷对的催化中的重要作用。活性和二聚体中单体亚基的相对取向之间没有显着关系。
The effect of individual positively charged residues on the orientation in the membrane was analyzed in three dual-topology transporters of the small multidrug resistance (SMR) family: AAVE4701aave of Acidovorax avenae, EMREecol of Escherichia coli, and RRUA0272rrub of Rhodospirillum rubrum. It is shown that (i) individual positive charges have different impacts on the orientation, (ii) positive charges that are conserved in the three different proteins do not have the same impact on the orientation, (iii) positive charges in odd- and even-numbered loops have different impacts, (iv) for some, but not all, the impact depends on the presence of other positive charges, and (v) proteins from which all positive charges are removed in some cases are dual-topology proteins and in other cases have a single orientation. A small number of positive charges placed in the loops of the latter proteins results in the violation of the so-called positive-inside rule that has been reported previously [Kolbusz, M. A., et al. (2010) J. Mol. Biol. 402, 127-138]. We conclude that each positive charge shifts the distribution between the two orientations toward the state that has the positive charge in the cytoplasm but that intrinsic factors other than positive charges determine the orientation as well. The ability of the mutants of AAVE4701aave and EMREecol to confer resistance against ethidium bromide revealed an essential role in catalysis for a conserved pair of positive charges in the second loop. No significant relation between activity and the relative orientation of the monomeric subunits in the dimer could be demonstrated.
DOI：
10.1073/pnas.0306533101
发表时间：
2004-02-10
影响因子：
11.1
作者：
Elbaz, Y;Steiner-Mordoch, S;Schuldiner, S
通讯作者：
Schuldiner, S
影响因子：
13.8
作者：
Schuldiner, Shimon
通讯作者：
Schuldiner, Shimon