Cullin C, Baudin-Baillieu A, Guillemet E, Ozier-Kalogeropoulos O
Centre de Génétique Moléculaire du CNRS, Laboratoire Propre Associé à l'Université Pierre et Marie Curie, Gif-sur-Yvette, France.
Yeast. 1996 Dec;12(15):1511-8. doi: 10.1002/(sici)1097-0061(199612)12:15<1511::aid-yea41>3.0.co;2-b.
We have analysed the function of the open reading frame (ORF) YCL09C. The deletion of this ORF from chromosome III does not affect the physiology of the corresponding yeast strain enough to give a distinct phenotype. Nevertheless a computational analysis reveals high homology between this ORF and the enterobacterial genes encoding the regulatory subunit of acetolactate synthase. We have therefore tested the possibility that yc109cp is the regulatory subunit of yeast acetolactate synthase by in vitro enzymatic analysis. The acetolactate synthase was previously shown to be retroinhibited by its final product valine. In Escherichia coli this retro-control is assured by the regulatory subunit. Using a yeast strain carrying a complete deletion of YCL09C, we have observed the loss of such retro-inhibition. These results together with the computational predictions show that YCL09C encodes the regulatory subunit of yeast acetolactate synthase.
我们分析了开放阅读框（ORF）YCL09C的功能。从第三条染色体上删除该ORF对相应酵母菌株的生理功能影响不大，不足以产生明显的表型。然而，一项计算分析表明，该ORF与编码乙酰乳酸合酶调节亚基的肠杆菌基因具有高度同源性。因此，我们通过体外酶分析测试了yc109cp是否为酵母乙酰乳酸合酶调节亚基的可能性。先前已证明乙酰乳酸合酶会被其终产物缬氨酸逆向抑制。在大肠杆菌中，这种逆向控制由调节亚基来保证。使用完全缺失YCL09C的酵母菌株，我们观察到这种逆向抑制作用的丧失。这些结果与计算预测结果共同表明，YCL09C编码酵母乙酰乳酸合酶的调节亚基。
