title: Inhibition of pectin methyl esterase activity by green tea catechins.
abstract: Pectin methyl esterases (PMEs) and their endogenous inhibitors are involved in the regulation of many processes in plant physiology, ranging from tissue growth and fruit ripening to parasitic plant haustorial formation and host invasion. Thus, control of PME activity is critical for enhancing our understanding of plant physiological processes and regulation. Here, we report on the identification of epigallocatechin gallate (EGCG), a green tea component, as a natural inhibitor for pectin methyl esterases. In a gel assay for PME activity, EGCG blocked esterase activity of pure PME as well as PME extracts from citrus and from parasitic plants. Fluorometric tests were used to determine the IC50 for a synthetic substrate. Molecular docking analysis of PME and EGCG suggests close interaction of EGCG with the catalytic cleft of PME. Inhibition of PME by the green tea compound, EGCG, provides the means to study the diverse roles of PMEs in cell wall metabolism and plant development. In addition, this study introduces the use of EGCG as natural product to be used in the food industry and agriculture.
authors.affiliation: Rowland Institute at Harvard, 100 Edwin H. Land Boulevard, Cambridge, MA 02141, United States. lewis@rowland.harvard.edu
authors.forename: Kristin C
authors.initials: KC
authors.lastname: Lewis
authors.forename: Tzvia
authors.initials: T
authors.lastname: Selzer
authors.forename: Chen
authors.initials: C
authors.lastname: Shahar
authors.forename: Yael
authors.initials: Y
authors.lastname: Udi
authors.forename: Dmitry
authors.initials: D
authors.lastname: Tworowski
authors.forename: Irit
authors.initials: I
authors.lastname: Sagi
mesh_terms: D028241:Camellia sinensis / Q000737:chemistry*; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D002392:Catechin / Q000031:analogs & derivatives* / Q000378:metabolism; D002957:Citrus / Q000201:enzymology; D005470:Fluorometry; D018551:Solanum lycopersicum / Q000201:enzymology; D010936:Plant Extracts / Q000378:metabolism; D013379:Substrate Specificity; D013662:Tea / Q000737:chemistry*
chemical_list: D010936:Plant Extracts; D013662:Tea; D002392:Catechin; C045651:epigallocatechin gallate; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase