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Carbohydrate esterases of family 2 are 6‐ O ‐deacetylases
Author(s) -
Topakas Evangelos,
Kyriakopoulos Sarantos,
Biely Peter,
Hirsch Ján,
Vafiadi Christina,
Christakopoulos Paul
Publication year - 2010
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/j.febslet.2009.11.095
Subject(s) - chemistry , esterase , acetylation , clostridium thermocellum , enzyme , biochemistry , carbohydrate , xylose , vinyl acetate , glycoside hydrolase , glycerol , stereochemistry , organic chemistry , copolymer , fermentation , cellulase , gene , polymer
Three acetyl esterases (AcEs) from the saprophytic bacteria Cellvibrio japonicus and Clostridium thermocellum , members of the carbohydrate esterase (CE) family 2, were tested for their activity against a series of model substrates including partially acetylated gluco‐, manno‐ and xylopyranosides. All three enzymes showed a strong preference for deacetylation of the 6‐position in aldohexoses. This regioselectivity is different from that of typical acetylxylan esterases (AcXEs). In aqueous medium saturated with vinyl acetate, the CE‐2 enzymes catalyzed transacetylation to the same position, i.e., to the primary hydroxyl group of mono‐ and disaccharides. Xylose and xylooligosaccharides did not serve as acetyl group acceptors, therefore the CE‐2 enzymes appear to be 6‐ O ‐deacetylases.