新型白化型除草剂靶标酶对羟苯基丙酮酸双加氧酶及其耐性转基因植物研究进展*

对羟苯基丙酮酸双加氧酶(ρ-hydroxyphenylpyruvate dioxygenase，HPPD；EC 1.13.11.27)催化生物体内对羟苯基丙酮酸与O2作用形成尿黑酸的反应，是植物体中质体醌和生育酚生物合成途径的关键酶。当其活性受到抑制时，植物体中作为类胡萝卜素生物合成途径中最终电子受体和光合链电子传递体的质体醌的生物合成受阻，进而导致类胡萝卜素合成减少，光合链电子传递受阻，致使植物体出现白化症状。目前已经开发了多种以HPPD为靶标的除草剂，该类除草剂及抗除草剂转基因植物研究具有广阔的前景。对这一新型白化型除草剂靶标酶以及耐该类除草剂转基因植物的研究进展作了简要综述。

Advances in a New Target for Bleaching-herbicide p-hydroxyphenylpyruvate Dioxygenase and Herbicide-resistant Transgenic Plants

p-Hydroxyphenylpymvate dioxygenase ( HPPD) catalyzes the formation of homogentisate from phydroxyphenylpyruvate and O_2. In plant, HPPD is one of the key enzymes in the biosynthesis of prenylquinones plastoquinones and tocopherol. Since plastoquinone is the final electron acceptor in carotenoid biosynthesis, a lack of this component in thylakoids impairs carotenoid biosynthesis, which results in bleaching symptoms in leaves as in phytoene desaturase inhibition. Currently, three bleaching herbicide families which target for HPPD,isoxazoles, triketones, and pyrazoles, have been reported. Some kinds of this herbicides family are used control of a wide range of important broadleaf and grass weeds in maize and rice filed. Advances in this new bleachingherbicide target enzyme and herbicide-resistant transgenic plants were overviewed.