title: The carbohydrate-binding module of Fragaria × ananassa expansin 2 (CBM-FaExp2) binds to cell wall polysaccharides and decreases cell wall enzyme activities "in vitro".
abstract: 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 (K(ad) = 33.6 ± 0.44 mL g(-1), K(ad) = 11.37 ± 0.87 mL g(-1), K(ad) = 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.
authors: IIB-INTECH (CONICET-UNSAM), Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, Camino de Circunvalación Laguna, km 6, (B7130IWA) Chascomús, Pcia, Buenos Aires, Argentina.
authors: Cristina
authors: C
authors: Nardi
authors: Cristian
authors: C
authors: Escudero
authors: Natalia
authors: N
authors: Villarreal
authors: Gustavo
authors: G
authors: Martínez
authors: Pedro Marcos
authors: PM
authors: Civello
mesh_terms: D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism; D004926:Escherichia coli; D031985:Fragaria / Q000235:genetics* / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D010368:Pectins / Q000378:metabolism; D010937:Plant Growth Regulators / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011134:Polysaccharides / Q000378:metabolism*; D011485:Protein Binding / Q000235:genetics; D014990:Xylans / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D011134:Polysaccharides; D014990:Xylans; C095825:expansin protein, plant; D010368:Pectins; D002482:Cellulose