Changes in microsomal hemoprotein content and glucose 6‐phosphatase activity during low‐temperature acclimation of Tetrahymena pyriformis

FEBS Letters

Takeda, Tomoo¹  Fukushima, Hirofumi¹  Sasaki, Noboru¹  Watanabe, Takehito¹  Nozawa, Yoshinori¹ 

[1] Department of Biochemistry, Gifu University School of Medicine, Gifu, Japan

关键词: Tetrahymena;    Microsome;    Hemoprotein;    Temperature acclimation;    Glucose 6-phosphatase;   

DOI  :  10.1016/0014-5793(83)81021-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

To examine the temperture-associated alterations in microsomal enzymes in an eukaryote, Tetrahymena cells were transferred from 39.5–15°C. The content of cytochrome b-560_ms, a cytochrome similar to but not identical with liver microsomal cytochrome b ₅, was slightly increased within 2 h after temperature shift-down, then gradually decreased, and reached the cytochrome b-560_ms level of the 15°C-isothermally grown cells within 10 h following the temperature-shift. Cytochrome P-450 was not detected in Tetrahymena microsomes. The presence of a co-binding hemoprotein with a main peak at 420 nm was, however, observed. The amount of this hemoprotein was unchanged for 2 h after cold-shift. Later, it increased gradually and reached the maximum level at 10 h. Glucose 6-phosphatase activity increased slightly at 10 h, when cell division had already been regained. We conclude that cytochrome b-560_ms, which is linked to the desaturase, may be essential for short-term adaptation (2 h after shift), while the amount of co-binding hemoprotein and the activity of glucose 6-phosphatase would be associated with long-term adaptation (10 h after temperature shift) in Tetrahymena cells.

【 授权许可】

Unknown