The carbohydrate-binding module of Fragaria × ananassa expansin 2 (CBM-FaExp2) binds to cell wall polysaccharides and decreases cell wall enzyme activities "in vitro"

A putative carbohydrate binding module (CBM) from strawberry (Fragaria × ananassa Duch.) expansin 2 (CBM-FaExp2) was cloned and the encoding protein was over-expressed in Escherichia coli and purified in order to evaluate its capacity to bind different cell wall polysaccharides "in vitro"....

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Bibliographic Details
Authors: Nardi, Cristina Fernanda, Escudero, Cristian Martín, Villarreal, Natalia Marina, Martínez Gustavo A., Civello, Pedro Marcos
Format: article
Status:Published version
Publication Date:2013
Country:Argentina
Institution:Consejo Nacional de Investigaciones Científicas y Técnicas
Repository:CONICET Digital (CONICET)
Language:English
OAI Identifier:oai:ri.conicet.gov.ar:11336/181427
Online Access:http://hdl.handle.net/11336/181427
Access Level:Open access
Keyword:CBM
CELL WALL
EXPANSIN
HYDROLASES
STRAWBERRY
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Description
Summary:A putative carbohydrate binding module (CBM) from strawberry (Fragaria × ananassa Duch.) expansin 2 (CBM-FaExp2) was cloned and the encoding protein was over-expressed in Escherichia coli and purified in order to evaluate its capacity to bind different cell wall polysaccharides "in vitro". The protein CBM-FaExp2 bound to microcrystalline cellulose, xylan and pectin with different affinities (Kad = 33. 6 ± 0. 44 mL g-1, Kad = 11. 37 ± 0. 87 mL g-1, Kad = 10. 4 ± 0. 19 mL g-1, respectively). According to "in vitro" enzyme assays, this CBM is able to decrease the activity of cell wall degrading enzymes such as polygalacturonase, endo-glucanase, pectinase and xylanase, probably because the binding of CBM-FaExp2 to the different substrates interferes with enzyme activity. The results suggest that expansins would bind not only cellulose but also a wide range of cell wall polymers.