Structure of the rotor of the V-type Na+-ATPase from Enterococcus hirae
Structure of the rotor of the V-type Na+-ATPase from Enterococcus hirae
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DOI：
10.1126/science.1110064
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发表时间：
2005-04-29
期刊：
影响因子：
56.9
通讯作者：
Walker, JE
中科院分区：
文献类型：
--
作者：
Murata, T;Yamato, I;Walker, JE
扁平肠球菌液泡型（v型）钠离子泵送腺苷三磷酸酶（Na+- atpase）的膜转子环由10个NtpK亚基组成，它们分别与其他v - atpase和F1F0-或f - atpase中发现的16千顿和8千顿的蛋白肽同源。每个NtpK亚基都有四个跨膜螺旋，在螺旋2和4之间的一个深埋在膜上的位置上有一个钠离子结合，其中包括必需的残基谷氨酸-139。该位点可能通过亚基Ntpl中的两个半通道连接到膜表面，环围绕其旋转。转子和催化结构域之间的对称失配似乎是V-和f - atp酶的内在特征。
The membrane rotor ring from the vacuolar-type (V-type) sodium ion-pumping adenosine triphosphatase (Na+-ATPase) from Enterococcus hirae consists of 10 NtpK subunits, which are homologs of the 16-kilodalton and 8-kilodalton proteotipids found in other V-ATPases and in F1F0- or F-ATPases, respectively. Each NtpK subunit has four transmembrane a helices, with a sodium ion bound between helices 2 and 4 at a site buried deeply in the membrane that includes the essential residue glutamate-139. This site is probably connected to the membrane surface by two half-channels in subunit Ntpl, against which the ring rotates. Symmetry mismatch between the rotor and catalytic domains appears to be an intrinsic feature of both V- and F-ATPases.