CAJ | 학술논문

存在于细菌和植物叶绿体中的双精氨酸(Tat)蛋白质转运系统能将底物蛋白以折叠的状态进行跨膜转运。该系统中的单次跨膜膜蛋白 TatA 通过自身寡聚形成转运底物蛋白的通道。该文应用液体核磁共振方法解析了枯草芽孢杆菌 TatAy蛋白在十二烷基胆碱磷酸胶束中的结构，它是由一个跨膜螺旋(TMH)和一个两亲性螺旋(APH)构成的L型结构。通过与已经报道的枯草芽孢杆菌TatAd蛋白的结构比较，该文能够鉴定出参与维持L型构象的重要氨基酸残基，并指出了TatA蛋白家族中若干较为保守的结构特征。在此基础上，该文讨论了保守残基在 TatA 通道形成过程中可能发挥的作用。
존재우세균화식물협록체중적쌍정안산(Tat)단백질전운계통능장저물단백이절첩적상태진행과막전운。해계통중적단차과막막단백 TatA 통과자신과취형성전운저물단백적통도。해문응용액체핵자공진방법해석료고초아포간균 TatAy단백재십이완기담감린산효속중적결구，타시유일개과막라선(TMH)화일개량친성라선(APH)구성적L형결구。통과여이경보도적고초아포간균TatAd단백적결구비교，해문능구감정출삼여유지L형구상적중요안기산잔기，병지출료TatA단백가족중약간교위보수적결구특정。재차기출상，해문토론료보수잔기재 TatA 통도형성과정중가능발휘적작용。
The twin-arginine transport (Tat) systems in bacteria and plant chloroplasts translocate cargo proteins across cellular membranes in their folded states. The single-pass transmembrane protein TatA forms the protein translocation channel via self-oligomerization. Herein, we present the structure ofBacillus subtilis TatAy protein in dodecylphosphocholine micelles determined by solution NMR method. TatAy adopts an L-shaped conformation formed by a transmembrane helix (TMH) and an amphipathic helix (APH). Structural comparison of TatAy protein with the previously reportedB. subtilis TatAd protein highlights essential residues at the hinge region for maintaining the L-shaped conformation, and suggests a few conserved structural features for the TatA protein family. Possible roles for the conserved residues in the TatA channel formation are discussed.