NMR structures of a mitochondrial transit peptide from the green alga Chlamydomonas reinhardtii

FEBS Letters

Lancelin, Jean-Marc¹  Gans, Pierre¹  Bouchayer, Eftychia¹  Arlaud, Gérard J.¹  Jacquot, Jean-Pierre²  Bally, Isabelle¹ 

[1] Institut de Biologie Structurale CEA-CNRS, 41, Avenue des Martyrs, F-38027 Grenoble, France;Laboratoire de Physiologie Végétale Moléculaire, Bâtiment 630, Unité Associée au CNRS 1128, Université de Paris-Sud, F-91405 Orsay, France

关键词: Mitochondrial protein import;    Transit peptide;    ATP synthase;    Peptide synthesis;    NMR structure;    Chlamydomonas reinhardtii;    CD;    circular dichroism;    TFE;    2;    2;    2-trifluoroethanol;    cTP;    choloroplastic transit peptide;    mTP;    mitochondrial transit peptide;    rMD;    restrained molecular dynamic;    R.m.s.;    root-mean-square;    R.m.s.d.;    R.m.s. deviation;   

DOI  :  10.1016/0014-5793(96)00734-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The 26-amino-acid pre-sequence of the ATP synthase βs subunit that directs the protein from the cytosol to mitochondria in the unicellular green alga Chlamydomonas reinhardtii has been synthesised and analysed using NMR spectroscopy/circular dichroism and compared to a chloroplast transit peptide from the same organism. The results demonstrate that the peptide, though mainly unstructured in water, undergoes a strong conformational change in a 36% water/64% 2,2,2-trifluoroethanol mixture. In this solvent condition, an α-helix was characterised by NMR from residue 2 to 26. Structure calculations under NMR restraints lead to a population of models of which 60% are kinked at position 9–10. Structural analysis indicates two hydrophobic sectors on the models with a discontinuity at the 9–10 kink level. The structures suggest a different interaction mode with the mitochondrial membrane compared to the chloroplast transit peptide.

【 授权许可】

Unknown