Inhibition of pectin methyl esterase activity by green tea catechins

Kristin C Lewis,Tzvia Selzer,Chen Shahar,Yael Udi,Dmitry Tworowski,Irit Sagi

doi:10.1016/j.phytochem.2008.08.012

Kristin C Lewis, Tzvia Selzer + Show 4 more

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https://doi.org/10.1016/j.phytochem.2008.08.012

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Journal: Phytochemistry	Publication Date: Sep 29, 2008
Citations: 80	License type: cc-by

Affiliation: Weizmann Institute of Science

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.

Highlights

Pectin methyl esterase (PME), which modifies esterified homogalacturonan components of pectin found in plant cell walls, is a critical enzyme for tissue remodeling, growth, and fruit maturation, among other processes (Brummell, 2006; Derbyshire et al, 2007; Jarvis et al, 2003)
We have found that green tea catechin extract inhibits citrus and tomato PME activity in vitro, and inhibits parasitic plant PME extracts from both dodder (Cuscuta pentagona) and Indian paintbrush (Castilleja indivisa), representatives of two large families of parasitic plants, the Cuscutaceae and Orobanchaceae
We have found that green tea catechins can be used to inhibit pectin methyl esterase activity across plant taxa, and that the inhibitory interaction occurs at the substrate binding site of PME

Summary

Graphical Abstract

Pectin methyl esterases and their endogenous inhibitors are involved in many processes in plant physiology. Exogenous inhibitors of PME can be used to further our understanding of these processes. We identify the green tea catechin epigallocatechin gallate as a natural inhibitor of pectin methyl esterases from multiple taxa. INHIBITION OF PECTIN METHYL ESTERASE ACTIVITY BY GREEN TEA CATECHINS

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