Reversible denaturation of cyclosporin synthetase by urea

FEBS Letters

Lawen, Alfons¹  Dittmann, Joachim¹  Kleinkauf, Horst¹  Vaillant, François² 

[1] Institut für Biochemie und Molekulare Biologie, Technische Universität Berlin, Franklinstraße 29, OE 2, D-10587 Berlin, Germany;Department of Biochemistry and Molecular Biology, Monash University, Clayton 3168, Australia

关键词: Biosynthesis;    Cyclosporin synthetase;    Fluorescence spectrum;    Folding;    Multidomain enzyme;    Abu;    l-2-aminobutyric acid;    AdoMet;    [14C]AdoMet;    Bmt;    CyA;    cyclosporin A;    cyclo-(d-Ala-MeLeu);    Me;    N-methyl-;   

DOI  :  10.1016/0014-5793(96)00014-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The reversible denaturation of the multifunctional polypeptide, cyclosporin synthetase, by urea was analyzed. It is possible to discriminate between at least two stages of enzyme denaturation. While at low urea concentration (up to 0.8 M) cyclosporin A formation is inhibited, synthesis of the diketopiperazine cyclo-(), a molecule representing a partial sequence of cyclosporin A is still detectable. At higher concentrations of urea the enzyme preparation is totally inactive. This inactivation is a consequence of conformational change(s) of cyclosporin synthetase as shown by fluorescence emission spectra of native and denatured enzyme. These data imply a consecutive folding/defolding mechanism for the different domains forming the multifunctional polypeptide.

【 授权许可】

Unknown