Identification and analysis of genes from Streptomyces pristinaespiralis encoding enzymes involved in the biosynthesis of the 4-dimethylamino-L-phenylalanine precursor of pristinamycin I
Identification and analysis of genes from Streptomyces pristinaespiralis encoding enzymes involved in the biosynthesis of the 4-dimethylamino-L-phenylalanine precursor of pristinamycin I
复制标题
DOI：
10.1046/j.1365-2958.1997.2031574.x
复制
发表时间：
1997-01-01
影响因子：
3.6
通讯作者：
Thibaut, D
中科院分区：
文献类型：
--
作者：
Blanc, V;Gil, P;Thibaut, D
通过对snbA附近的测序发现了四个pap基因（papA、papB、papC、papM），snbA是一种原始旋链霉菌基因，此前已证明该基因编码一种原始霉素I（PI）合成酶。从推导的氨基酸序列中观察到的同源性分析表明，这四个基因可能参与PI前体4-二甲氨基-L-苯丙氨酸（DMPAPA）的生物合成。这一点在S. pristinaespiralis导致PI-表型，其通过向培养基中添加DMPAPA而逆转。当papM在大肠杆菌中过表达并将相应的蛋白纯化至均一时，得到了进一步的证实。它催化4-氨基-L-苯丙氨酸的两个连续的N-甲基化步骤，通过4-甲氨基-L-苯丙氨酸生成DMPAPA。这些结果使我们能够为四个pap基因中的每一个分配功能，并提出DMPAPA的生物合成途径。
Four pap genes (papA, papB, papC, papM) were found by sequencing near to snbA, a Streptomyces pristinaespiralis gene which was previously shown to encode one of the pristinamycin I (PI) synthetases. Analysis of the homologies observed from the deduced amino acid sequences suggested that these four genes could be involved in the biosynthesis of the PI precursor 4-dimethylamino-L-phenylalanine (DMPAPA). This was first verified when disruption of papA in S. pristinaespiralis led to a PI- phenotype, which was reversed by the addition of DMPAPA into the culture medium. Further confirmation was obtained when papM was overexpressed in Escherichia coli and the corresponding protein purified to homogeneity. It catalysed the two successive N-methylation steps of 4-amino-L-phenylalanine leading to DMPAPA via 4-methylamino-L-phenylalanine. These results allowed us to assign a function to each of the four pap genes and to propose a biosynthetic pathway for DMPAPA.