Kitamura Kenji, Kinsui Eldaa Zefany Banami
a Center for Gene Science , Hiroshima University , Higashi-Hiroshima , Japan.
Biosci Biotechnol Biochem. 2018 Mar;82(3):540-546. doi: 10.1080/09168451.2018.1433994. Epub 2018 Feb 15.
In the yeast Saccharomyces cerevisiae, all strains possess a gene for the evolutionarily conserved POT family peptide transporter, Ptr2; however, the genes for a novel FOT family transporter were found only in some wine brewing strains. The substrate specificity of the POT and FOT family of transporters was compared. Among the naturally occurring oligopeptides that were tested, Lys-Leu and Arg-Phe were Ptr2-specific substrates. Artificial dipeptide aspartame was imported specifically through the FOT transporter, but the structurally similar Asp-Phe was a substrate of both FOT and Ptr2 transporters. Furthermore, only the FOT transporter was important for high sensitivity to an antibiotic puromycin. These results demonstrate that the POT and FOT family of transporters have distinct substrate preferences although both transporters import overlapping dipeptide substrates. Having POT and FOT transporters is advantageous for cells to acquire nutrients, but also detrimental when these cells are exposed to the toxic molecules of their substrates.
在酿酒酵母中，所有菌株都拥有一个与进化保守的POT家族肽转运体Ptr2相关的基因；然而，一种新型FOT家族转运体的基因仅在一些酿酒菌株中被发现。对POT和FOT家族转运体的底物特异性进行了比较。在所测试的天然存在的寡肽中，Lys-Leu和Arg-Phe是Ptr2特异性底物。人工二肽阿斯巴甜通过FOT转运体被特异性导入，但结构相似的Asp-Phe是FOT和Ptr2转运体的底物。此外，只有FOT转运体对抗生素嘌呤霉素的高敏感性很重要。这些结果表明，尽管两种转运体都能转运重叠的二肽底物，但POT和FOT家族转运体具有不同的底物偏好。拥有POT和FOT转运体有利于细胞获取营养，但当这些细胞暴露于其底物的有毒分子时也会产生不利影响。
