Glawischnig E
Lehrstuhl für Genetik, Technische Universität München, Am Hochanger 8, 85350 Freising, Germany.
Biochem Soc Trans. 2006 Dec;34(Pt 6):1206-8. doi: 10.1042/BST0341206.
The biosynthesis of camalexin, the main phytoalexin of the model plant Arabidopsis thaliana, involves at least two CYP (cytochrome P450) steps. It is synthesized from tryptophan via indole-3-acetaldoxime in a reaction catalysed by CYP79B2 and CYP79B3. Based on the pad3 mutant phenotype, CYP71B15 (PAD3) had also been suggested as a camalexin biosynthetic gene. CYP71B15 catalyses the final step in camalexin biosynthesis, as recombinant CYP71B15 and microsomes from Arabidopsis leaves expressing functional PAD3 converted dihydrocamalexic acid into camalexin. The biosynthetic pathway is co-ordinately induced, strictly localized to the site of pathogen infection. This provides a model system to study the regulation of CYP enzymes involved in phytoalexin biosynthesis.
拟南芥作为模式植物，其主要植保素——camalexin的生物合成至少涉及两个细胞色素P450（CYP）步骤。它由色氨酸经吲哚 - 3 - 乙醛肟，在CYP79B2和CYP79B3催化的反应中合成。基于pad3突变体表型，CYP71B15（PAD3）也被认为是一个camalexin生物合成基因。CYP71B15催化camalexin生物合成的最后一步，因为重组CYP71B15和来自表达功能性PAD3的拟南芥叶片的微粒体将二氢camalexic酸转化为camalexin。该生物合成途径是协同诱导的，严格定位于病原体感染部位。这提供了一个模型系统来研究参与植保素生物合成的CYP酶的调控。
