PMID: 15301540 , Related PDB ids: 1SQD, 1SQI, 1TFZ, 1TG5

Authors:

Yang C, Pflugrath JW, Camper DL, Foster ML, Pernich DJ, Walsh TA

Title:

Structural basis for herbicidal inhibitor selectivity revealed by comparison of crystal structures of plant and mammalian 4-hydroxyphenylpyruvate dioxygenases.

Journal:

Biochemistry. 2004 Aug 17;43(32):10414-23.

Abstract:

A high degree of selectivity toward the target site of the pest organism is a desirable attribute for new safer agrochemicals. To assist in the design of novel herbicides, we determined the crystal structures of the herbicidal target enzyme 4-hydroxyphenylpyruvate dioxygenase (HPPD; EC 1.13.11.27) from the plant Arabidopsis thaliana with and without an herbicidal benzoylpyrazole inhibitor that potently inhibits both plant and mammalian HPPDs. We also determined the structure of a mammalian (rat) HPPD in complex with the same nonselective inhibitor. From a screening campaign of over 1000 HPPD inhibitors, six highly plant-selective inhibitors were found. One of these had remarkable (>1600-fold) selectivity toward the plant enzyme and was cocrystallized with Arabidopsis HPPD. Detailed comparisons of the plant and mammalian HPPD-ligand structures suggest a structural basis for the high degree of plant selectivity of certain HPPD inhibitors and point to design strategies to obtain potent and selective inhibitors of plant HPPD as agrochemical leads.