Kinzel J J, Bhattacharjee J K
J Bacteriol. 1979 May;138(2):410-7. doi: 10.1128/jb.138.2.410-417.1979.
The role of pipecolic acid in the biosynthesis of lysine was investigated in Rhodotorula glutinis, an aerobic red yeast. Supplementation of pipecolic acid in the minimal medium supported the growth of mutants lys2, lys3, and lys5; alpha-aminoadipic acid supported the growth of lys5; but neither alpha-aminoadipic acid nor pipecolic acid supported the growth of mutants MNNG42 and MNNG37. During the growth of the appropriate mutants, pipecolic acid was removed from the growth medium and the intracellular pool. In tracer experiments, radioactivity from [(14)C]pipecolic acid was selectively incorporated into the cellular lysine of lys5 and the wild-type strain. l-Pipecolic acid-dependent enzyme activity did not require any cofactor and was inhibited by mercuric chloride and potassium cyanide. This activity was present in the wild-type strain and all of the mutants tested and was repressed in mutant lys5 when grown in the presence of higher concentration of lysine. The reaction product of pipecolic acid was converted to saccharopine by lys5 enzyme in the presence of glutamate and reduced nicotin-amide adenine dinucleotide phosphate. Mutant MNNG37 lacked the saccharopine dehydrogenase activity, indicating that this step is involved in the conversion of alpha-aminoadipic acid and pipecolic acid to lysine. Mutants MNNG37 and MNNG42 accumulated a p-dimethylaminobenzaldehyde-reacting product in the culture supernatant and in the intracellular pool. Chromatographic properties of the p-dimethylaminobenzaldehyde adduct and that of the pipecolic acid-dependent reaction product were similar. The reaction product and the accumulation product were characterized on the basis of mass and absorption spectra as alpha-aminoadipic-semialdehyde, which in solution remains in equilibrium with Delta(1)-piperideine-6-carboxylic acid. Since alpha-aminoadipic-semialdehyde is a known intermediate of the alpha-aminoadipic acid pathway for the biosynthesis of lysine, it is concluded that pipecolic acid is converted to lysine in R. glutinis via alpha-aminoadipic-semialdehyde and saccharopine.
在需氧红酵母粘红酵母中研究了哌啶酸在赖氨酸生物合成中的作用。在基本培养基中添加哌啶酸可支持lys2、lys3和lys5突变体的生长；α-氨基己二酸可支持lys5的生长；但α-氨基己二酸和哌啶酸均不支持MNNG42和MNNG37突变体的生长。在合适的突变体生长过程中，哌啶酸从生长培养基和细胞内池中被去除。在示踪实验中，[(14)C]哌啶酸的放射性被选择性地掺入lys5和野生型菌株的细胞赖氨酸中。L-哌啶酸依赖性酶活性不需要任何辅因子，并受到氯化汞和氰化钾的抑制。这种活性存在于野生型菌株和所有测试的突变体中，当在高浓度赖氨酸存在下生长时，在突变体lys5中受到抑制。在谷氨酸和还原型烟酰胺腺嘌呤二核苷酸磷酸存在下，lys5酶将哌啶酸的反应产物转化为酵母氨酸。突变体MNNG37缺乏酵母氨酸脱氢酶活性，表明该步骤参与α-氨基己二酸和哌啶酸向赖氨酸的转化。突变体MNNG37和MNNG42在培养上清液和细胞内池中积累了一种与对二甲基氨基苯甲醛反应的产物。对二甲基氨基苯甲醛加合物和哌啶酸依赖性反应产物的色谱性质相似。根据质谱和吸收光谱将反应产物和积累产物鉴定为α-氨基己二醛半醛，其在溶液中与Δ(1)-哌啶-6-羧酸保持平衡。由于α-氨基己二醛半醛是赖氨酸生物合成的α-氨基己二酸途径的已知中间体，因此得出结论，在粘红酵母中哌啶酸通过α-氨基己二醛半醛和酵母氨酸转化为赖氨酸。
