Structure and dynamics of plant TatA in micelles and lipid bilayers studied by solution NMR
Structure and dynamics of plant TatA in micelles and lipid bilayers studied by solution NMR
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通过溶液核磁共振研究植物 TatA 在胶束和脂质双层中的结构和动力学
DOI：
10.1111/febs.14452
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发表时间：
1906
期刊：
影响因子：
--
通讯作者：
Mäler
中科院分区：
文献类型：
--
作者：
Pettersson;Tannert;Klösgen;Mäler
双精氨酸移位酶（达特）转运折叠蛋白穿过原核生物的细胞质膜和植物叶绿体的类囊体膜。在革兰氏阴性细菌和叶绿体中，易位子由三个亚基组成，TatA，TatB和TatC，其中TatA负责底物的实际膜易位。在此，我们使用溶液状态核磁共振报告了来自拟南芥的全功能C末端截短的“核心TatA”的结构、动力学和脂质相互作用。我们的研究结果表明，TatA由一个短的N-末端跨膜螺旋（TMH），一个短的连接接头（铰链）和一个长的区域，倾向于形成一个两亲性螺旋（APH）。使用15 N弛豫NMR结合无模型分析表征TatA的动力学。TMH具有良好结构的螺旋线的序参数特征，铰链的刚性稍差，而APH具有表示结构柔性的低阶参数。TMH是短的，具有令人惊讶的低溶剂保护，并且只有APH的第一部分在一定程度上受到保护。为了揭示洗涤剂中TatA的结构和动力学与脂质双层相比的可能差异，使用快速翻滚的双胞和大的单层囊泡。结果表明，在脂质存在下，TMH和APH中TatA的螺旋度均增加，并且TMH的N-末端部分明显更刚性。结果表明，植物TatA具有明显的结构可塑性和适应当地环境的能力。
The twin‐arginine translocase (Tat) transports folded proteins across the cytoplasmic membrane of prokaryotes and the thylakoid membrane of plant chloroplasts. In Gram‐negative bacteria and chloroplasts, the translocon consists of three subunits, TatA, TatB, and TatC, of which TatA is responsible for the actual membrane translocation of the substrate. Herein we report on the structure, dynamics, and lipid interactions of a fully functional C‐terminally truncated ‘core TatA’ fromArabidopsis thalianausing solution‐state NMR. Our results show that TatA consists of a short N‐terminal transmembrane helix (TMH), a short connecting linker (hinge) and a long region with propensity to form an amphiphilic helix (APH). The dynamics of TatA were characterized using15N relaxation NMR in combination with model‐free analysis. The TMH has order parameters characteristic of a well‐structured helix, the hinge is somewhat less rigid, while the APH has lower order parameters indicating structural flexibility. The TMH is short with a surprisingly low protection from solvent, and only the first part of the APH is protected to some extent. In order to uncover possible differences in TatA's structure and dynamics in detergent compared to in a lipid bilayer, fast‐tumbling bicelles and large unilamellar vesicles were used. Results indicate that the helicity of TatA increases in both the TMH and APH in the presence of lipids, and that the N‐terminal part of the TMH is significantly more rigid. The results indicate that plant TatA has a significant structural plasticity and a capability to adapt to local environments.
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影响因子：
64.8
作者：
Long, Stephen B.;Tao, Xiao;MacKinnon, Roderick
通讯作者：
MacKinnon, Roderick
影响因子：
2.9
作者：
Lau, Tong-Lay;Partridge, Anthony W.;Ulmer, Tobias S.
通讯作者：
Ulmer, Tobias S.
影响因子：
3.2
作者：
Lee, PA;Buchanan, G;Palmer, T
通讯作者：
Palmer, T
影响因子：
11.4
作者：
BARKAN, A;MILES, D;TAYLOR, WC
通讯作者：
TAYLOR, WC
影响因子：
3.1
作者：
Marques, JP;Dudeck, I;Klösgen, RB
通讯作者：
Klösgen, RB