Yeast glycogen phosphorylase: Kinetic properties compared with muscle and potato enzymes.

• TANABE Satoshi

  Department of Agricultural Chemistry, Faculty of Agriculture, Tohoku University

• KOBAYASHI Mikihiko

  Department of Agricultural Chemistry, Faculty of Agriculture, Tohoku University

• MATSUDA Kazuo

  Department of Agricultural Chemistry, Faculty of Agriculture, Tohoku University

抄録

The apparent Km values of yeast α-glucan phosphorylase [EC 2.4.1.1] for glucose 1-phosphate, glycogen and maltopentaose were 1.3mM, 0.10mM and 8.8mM, respectively. The Km values for maltopentaose clearly distinguished the muscle and yeast enzymes from the potato enzyme. Comparison of the Km values for maltooligosaccharides in the directions of both glycogen synthesis and degradation showed the similarity of the muscle and yeast enzymes. Affinity-gel electrophoresis indicated that the dissociation constant of the yeast enzyme for maltoheptaose was 0.23mM, which was 26-fold smaller than the Km value for maltoheptaose (5.9mM). Inhibition of the yeast enzyme activity by glucose 6-phosphate and UDP-glucose was much stronger than that by fructose 6-phosphate and fructose 1, 6-bisphosphate. Moreover, tryptic inactivation of the yeast enzyme was greatly increased by UDP-glucose and glucose 6-phosphate. Based on the kinetic properties, a regulatory mechanism of the yeast phosphorylase was discussed in comparison with those for the muscle and potato phosphorylases.

収録刊行物

• Agricultural and Biological Chemistry

  Agricultural and Biological Chemistry 52 (3), 757-764, 1988

  公益社団法人 日本農芸化学会

キーワード

• General Agricultural and Biological Sciences
• General Biochemistry, Genetics and Molecular Biology

詳細情報

• CRID: 1390282681440494976
• NII論文ID: 110006323705
• NII書誌ID: AA00515312
• DOI: 10.1271/bbb1961.52.757
• COI: 1:CAS:528:DyaL1cXitVSku7k%3D
• ISSN: 18811280
• ISSN: 00021369
• 本文言語コード: en
• データソース種別:
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  • Crossref
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• 抄録ライセンスフラグ: 使用不可