Pyruvate carboxylase from Rhizopus arrhizus

FEBS Letters

Osmani, S.A.²  Mayer, F.¹  Scrutton, M.C.² 

[1] Institute für Mikrobiology der Universitat Gottingen, Grisebachstrasse 8, D-4000 Gottingen, FRG;Department of Biochemistry. King's College, The Strand, London WC2R2LS, England

关键词: Pyruvate carboxylase;    Rhizopus arrhizus;    Electron microscope;    EDTA;    Acetyl-CoA;    2-Oxoadipate;   

DOI  :  10.1016/0014-5793(85)80110-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Pyruvate carboxylase purified from Rhizopus arrhizus exhibits projections when examined in the electron microscope which indicate that this enzyme is a tetrameric molecule in which the subunits are arranged at the corners of a tetrahedron. The tetrameric molecule is stabilised by addition of acetyl-CoA or of pyruvate but is labilised in the presence of 2-oxoadipate. Addition of EDTA causes a decrease in the stability of the tetrameric molecule with a time course similar to that observed for loss of acetyl-CoA-dependent catalytic activity [(1984) FEBS Lett. 127, 157-160]. The data suggest that the hysteretic responses induced by exposure to EDTA are associated with dissociation of the tetrameric molecule to dimers and monomers having a decreased sensitivity to allosteric activation.

【 授权许可】

Unknown