title: Hydrolysis of pectins with different degrees and patterns of methylation by the endopolygalacturonase of Fusarium moniliforme.
abstract: The mode of action of the endopolygalacturonase from Fusarium moniliforme was studied towards a series of pectins with different amounts and distribution patterns of methyl-ester groups. The enzyme hydrolysed the linkages between two galacturonic acid residues according to a multi-chain attack mechanism, at least at the early stage of the reaction. The final percentage of hydrolysis decreased with increasing the degree of methylation. The distribution pattern of the methyl groups affected the rate of hydrolysis as well as the final percentage of hydrolysis, a blockwise distribution being more favourable than a random one. The final products, as analysed by mass spectrometry, included methyl-esterified oligogalacturonates. The detailed analysis of the structure of the oligomers showed that the enzyme was able to accommodate methylated galacturonic acid in its active site, but that methyl-esterification negatively affected the affinity of the enzyme.
authors: Unité de Recherche sur les Polysaccharides, leurs Organisations et Interactions, INRA, B.P. 71627, 44316 Nantes Cedex 03, France. bonnin@nantes.inra.fr
authors: E
authors: E
authors: Bonnin
authors: A
authors: A
authors: Le Goff
authors: R
authors: R
authors: Körner
authors: J
authors: J
authors: Vigouroux
authors: P
authors: P
authors: Roepstorff
authors: J-F
authors: JF
authors: Thibault
mesh_terms: D005670:Fusarium / Q000201:enzymology*; D006868:Hydrolysis; D007700:Kinetics; D008745:Methylation; D008970:Molecular Weight; D010368:Pectins / Q000737:chemistry / Q000378:metabolism*; D011096:Polygalacturonase / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013997:Time Factors
chemical_list: D010368:Pectins; D011096:Polygalacturonase