Copper chloride, an inhibitor of protein import into chloroplasts

FEBS Letters

Soll, Jürgen¹  Seedorf, Matthias¹ 

[1] Botanisches Institut, Universität Kiel, Am Botanischen Garten 1-9, D-24118 Kiel, Germany

关键词: Pisum sativum L.;    Precursor protein;    Crosslinking;    Copper chloride;    Protein import;    Chloroplast;    LSU;    SSU;    large;    small subunit of ribulose-1;    5-bis-phosphate carboxylase-oxygenase;    preSSU;    precursor form of SSU;    EtSH;    mercaptoethanol;    NEM;    N-ethylmaleimide;    OEP;    outer envelope protein;   

DOI  :  10.1016/0014-5793(95)00529-I

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have used the oxidant CuCl₂ to study its effect on precursor protein import into chloroplasts and on the components involved. CuCl₂ reversibly oxidizes thiol groups, which in turn, can form disulfide bridges. Concentrations of 40 μM CuCl₂ almost completely inhibit precursor protein binding and subsequent translocation into chloroplasts. This inhibitory effect is reversible by a dithiothreitol treatment. Disulfide bridges, which form upon oxidation by CuCl₂, are build up intramolecular and intermolecular, if the thiol groups are in close vicinity to each other. CuCl₂ can thus be used as a thiol cleavable crosslinker without an additional spacer distance between the two targets. When purified outer envelope membranes were treated with CuCl₂, a hetero oligomeric complex is detected, consisting of OEP86, OEP75 and OEP34, indicating the close vicinity and protein-protein interaction between polypeptides in situ, which are involved in protein translocation into chloroplasts.

【 授权许可】

Unknown