Induction of glyoxylate cycle enzymes in rat liver upon food starvation

FEBS Letters

Popov, Vasily N.¹  Schnarrenberger, Claus²  Volvenkin, Sergei V.¹  Igamberdiev, Abir U.¹ 

[1] Department of Plant Physiology and Biochemistry, Voronezh State University, Voronezh 394693, Russian Federation;Institute for Plant Physiology and Microbiology, Freie Universität Berlin, Königin-Luise-Str. 12-16a, D-14195 Berlin, Germany

关键词: Isocitrate lyase;    Malate synthase;    Rat liver;    Glyoxylate cycle;   

DOI  :  10.1016/0014-5793(96)00668-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The key enzymes of the glyoxylate cycle, isocitrate lyase and malate synthase, have been detected in liver of foodstarved rats. Activities became measurable 3 days and peaked 5 days after the beginning of starvation. Both enzymes were found in the peroxisomal cell fraction after organelle fractionation by isopycnic centrifugation. Isocitrate lyase was purified 112-fold by ammonium sulfate precipitation, and chromotography on DEAE-cellulose and Toyopearl HW-65. The specific activity of the purified enzyme was 9.0 units per mg protein. The K _m(isocitrate) was 68 μM and the pH optimum was at pH 7.4. Malate synthase was enriched 4-fold by ammonium sulfate precipitation. The enzyme had a K _m(acetyl-CoA) of 0.2 μM, a K _m(glyoxylate) of 3 mM and a pH optimum of 7.6.

【 授权许可】

Unknown