Maragoudakis M E, Holmes H, Strassman M
J Bacteriol. 1967 May;93(5):1677-80. doi: 10.1128/jb.93.5.1677-1680.1967.
Homocitric acid (beta-hydroxy-beta-carboxyadipic acid; HC) is accumulated by a lysine-requiring yeast mutant when grown in a chemically defined medium, supplemented with limited amounts of lysine. A study of the formation of HC in relation to the depletion of lysine from the growth medium indicates that HC accumulated only when the concentration of lysine was low. The enzymatic formation of HC from alpha-ketoglutarate plus acetyl-coenzyme A in cell-free extracts of the same organism was also inhibited by lysine. The inhibitory effect of lysine on the formation of HC in both whole cells and cell-free extracts is indicative of the functional existence of a feedback control mechanism in the pathway for lysine biosynthesis in yeast.
高柠檬酸（β-羟基-β-羧基己二酸；HC）在化学限定培养基中生长且添加有限量赖氨酸时，会被一种需要赖氨酸的酵母突变体积累。一项关于高柠檬酸形成与生长培养基中赖氨酸消耗关系的研究表明，只有当赖氨酸浓度较低时，高柠檬酸才会积累。在同一生物体的无细胞提取物中，赖氨酸也会抑制由α-酮戊二酸和乙酰辅酶A酶促形成高柠檬酸的过程。赖氨酸对全细胞和无细胞提取物中高柠檬酸形成的抑制作用表明，酵母赖氨酸生物合成途径中存在反馈控制机制。
