Structural and thermodynamic characterization of the interaction between two periplasmic Treponema pallidum lipoproteins that are components of a TPR-protein-associated TRAP transporter (TPAT).
Structural and thermodynamic characterization of the interaction between two periplasmic Treponema pallidum lipoproteins that are components of a TPR-protein-associated TRAP transporter (TPAT).
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DOI：
10.1016/j.jmb.2012.04.001
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发表时间：
2012-06-29
影响因子：
5.6
通讯作者：
Norgard, Michael V.
中科院分区：
文献类型：
--
作者：
Brautigam, Chad A.;Deka, Ranjit K.;Schuck, Peter;Tomchick, Diana R.;Norgard, Michael V.
三聚体ATP非依赖性周质转运蛋白(TRAP-T)是一种细菌转运系统，与小分子进入细胞质有关。一个新发现的TRAP-T亚家族(TPATs)有四个组分。TRAP-TS和TPATs共有三个：P组分，一种配体结合蛋白，以及一个由M和Q组分组成的跨膜转运体(M和Q有时会融合形成一个单一的多肽)。TPAT与TRAP-T的区别在于存在一种称为“T组分”的独特蛋白质。在梅毒螺旋体中，这种蛋白质(TART)是一种可溶于水的三聚体，其原型每个都有一个穿孔。其各自的P组分(TatPT)在体外和体内都与TATT相互作用。在这项工作中，我们进一步表征了这种相互作用。两种蛋白质之间的两个复合体的共晶体结构证实，多达三个TatPT单体可以与TATT三聚体结合。TatPT的一个可能的配体结合裂隙与TATT的孔对齐，强烈提示T和PT之间的配体转移。我们使用定点突变和分析性超速离心法相结合的方法来获得相互作用的热力学参数。这些观察结果证实了观察到的晶体界面是在溶液中重现的。这些结果提示了一个关于TPATs转运疏水配体的分子机制的假说(S)。
Tripartite ATP-independent periplasmic transporters (TRAP-Ts) are bacterial transport systems that have been implicated in the import of small molecules into the cytoplasm. A newly discovered subfamily of TRAP-Ts (TPATs) has four components. Three are common to both TRAP-Ts and TPATs: the P component, a ligand-binding protein, and a transmembrane symporter apparatus comprising the M and Q components (M and Q are sometimes fused to form a single polypeptide). TPATs are distinguished from TRAP-Ts by the presence of a unique protein called the “T component”. In Treponema pallidum, this protein (TatT) is a water-soluble trimer whose protomers are each perforated by a pore. Its respective P component (TatPT) interacts with the TatT in vitro and in vivo. In this work, we further characterized this interaction. Co-crystal structures of two complexes between the two proteins confirm that up to three monomers of TatPT can bind to the TatT trimer. A putative ligand-binding cleft of TatPT aligns with the pore of TatT, strongly suggesting ligand transfer between T and PT. We used a combination of site-directed mutagenesis and analytical ultracentrifugation to derive thermodynamic parameters for the interactions. These observations confirm that the observed crystallographic interface is recapitulated in solution. These results prompt a hypothesis of the molecular mechanism(s) of hydrophobic ligand transport by the TPATs.
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影响因子：
3.2
作者：
BELISLE, JT;BRANDT, ME;NORGARD, MV
通讯作者：
NORGARD, MV
影响因子：
5.6
作者：
Deka, Ranjit K.;Brautigam, Chad A.;Norgard, Michael V.
通讯作者：
Norgard, Michael V.
DOI：
10.1107/s0907444909052925
发表时间：
2010-02
期刊：
Acta crystallographica. Section D, Biological crystallography
影响因子：
--
作者：
Adams PD;Afonine PV;Bunkóczi G;Chen VB;Davis IW;Echols N;Headd JJ;Hung LW;Kapral GJ;Grosse-Kunstleve RW;McCoy AJ;Moriarty NW;Oeffner R;Read RJ;Richardson DC;Richardson JS;Terwilliger TC;Zwart PH
通讯作者：
Zwart PH
影响因子：
14.9
作者：
Davis IW;Leaver-Fay A;Chen VB;Block JN;Kapral GJ;Wang X;Murray LW;Arendall WB 3rd;Snoeyink J;Richardson JS;Richardson DC
通讯作者：
Richardson DC
DOI：
10.1107/s0907444998003254
发表时间：
1998-09-01
期刊：
ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY
影响因子：
--
作者：
Brunger, AT;Adams, PD;Warren, GL
通讯作者：
Warren, GL