Eberhard J, Raesecke H R, Schmid J, Amrhein N
Institute of Plant Sciences, Swiss Federal Institute of Technology, Zürich.
FEBS Lett. 1993 Nov 15;334(2):233-6. doi: 10.1016/0014-5793(93)81718-f.
Chorismate mutase (EC 5.4.99.5) catalyzes the first step in the branch of the shikimate pathway which leads to the aromatic amino acids, phenylalanine and tyrosine. We have isolated a cDNA for this enzyme from the higher plant, Arabidopsis thaliana, by complementing a yeast strain (aro7) with a cDNA library from A. thaliana. This is the first chorismate mutase cDNA isolated from a plant. It encodes a protein of 334 amino acids. The identity of the deduced amino acid sequence is 41% to the chorismate mutase sequence from Saccharomyces cerevisiae. The N-terminal portion of the deduced amino acid sequence has no homology to the S. cerevisiae sequence but resembles known plastid-specific transit peptides. The A. thaliana chorismate mutase expressed in yeast revealed allosteric control by the three aromatic amino acids, as previously described for plastidic chorismate mutase isozymes.
分支酸变位酶（EC 5.4.99.5）催化莽草酸途径中通向芳香族氨基酸苯丙氨酸和酪氨酸的分支的第一步反应。我们通过用拟南芥的cDNA文库对酵母菌株（aro7）进行互补，从高等植物拟南芥中分离出了该酶的cDNA。这是从植物中分离出的首个分支酸变位酶cDNA。它编码一个由334个氨基酸组成的蛋白质。推导的氨基酸序列与酿酒酵母的分支酸变位酶序列的一致性为41%。推导的氨基酸序列的N端部分与酿酒酵母序列没有同源性，但类似于已知的质体特异性转运肽。在酵母中表达的拟南芥分支酸变位酶显示出受三种芳香族氨基酸的变构调控，这与之前对质体分支酸变位酶同工酶的描述一致。
