Analysis of a chemical plant defense mechanism in grasses
Analysis of a chemical plant defense mechanism in grasses
复制标题
DOI：
10.1126/science.277.5326.696
复制
发表时间：
1997-08-01
期刊：
影响因子：
56.9
通讯作者：
Gierl, A
中科院分区：
文献类型：
--
作者：
Frey, M;Chomet, P;Gierl, A
在禾本科植物中，环状异羟肟酸2，4-二羟基-1，4-苯并恶嗪-3-酮（DIBOA）和2，4-二羟基-7-甲氧基-1，4-苯并恶嗪-3-酮（DIMBOA）形成防御昆虫和微生物病原体的一部分。玉米中DIBOA生物合成需要五个基因，Bx 1至Bx 5。这五个基因的功能，聚集在4号染色体上，在体外证明。Bx 1编码色氨酸合酶，该酶是催化吲哚形成的同系物，用于产生次级代谢物而不是色氨酸，从而定义了从初级代谢到次级代谢的分支点。Bx 2至Bx 5编码细胞色素P450依赖性单加氧酶，其催化四个连续的羟基化和一个环扩张以形成高度氧化的DIBOA。
In the Gramineae, the cyclic hydroxamic acids 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA) and 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) form part of the defense against insects and microbial pathogens. Five genes, Bx1 through Bx5, are required for DIBOA biosynthesis in maize. The functions of these five genes, clustered on chromosome 4, were demonstrated in vitro. Bx1 encodes a tryptophan synthase a homolog that catalyzes the formation of indole for the production of secondary metabolites rather than tryptophan, thereby defining the branch point from primary to secondary metabolism. Bx2 through Bx5 encode cytochrome P450-dependent monooxygenases that catalyze four consecutive hydroxylations and one ring expansion to form the highly oxidized DIBOA.