Transmembrane segment 10 is important for substrate recognition in Ga12 and Hxt2 sugar transporters in the yeast Saccharomyces cerevisiae

FEBS Letters

Maeda, Mari¹  Kasahara, Michihiro¹  Shimoda, Eriko¹ 

[1] Laboratory of Biophysics, School of Medicine, Teikyo University, Hachioji, Tokyo 192-03, Japan

关键词: Sugar transport;    Substrate recognition;    Galactose;    Glucose;    Chimera;    Saccharomyces cerevisiae;    TM;    transmembrane segment;    PCR;    polymerase chain reaction;   

DOI  :  10.1016/0014-5793(96)00567-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A systematic series of chimeras between Gal2 galactose transporter and Hxt2 glucose transporter in yeast was produced to delineate the essential domain for substrate recognition. A domain of 101 amino acids close to the COOH-terminus that has been previously identified as the critics substrate recognition region was further divided into four subdomains, by introducing five restriction enzyme sites at exactly corresponding locations of both genes without changing coding amino acids. When each of all possible 16 modified genes was expressed, all the galactose transport-active chimeras were found to possess Ga12-derived transmembrane segment (TM) 10. Of the 35 amino acids in the TM10 region, only 12 differ between Ga12 and Hxt2, indicating that these 12 amino acids include the critical residue(s) responsible for the differential recognition of galactose and glucose in these transporters.

【 授权许可】

Unknown