|Cote, Gregory - Greg|
Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/20/1996
Publication Date: N/A
Citation: N/A Interpretive Summary:
Technical Abstract: The substrate specificities of purified acetylxylan esterases (AcXEs) from Schizophyllum commune and Streptomyces lividans were investigated on fully and partially acetylated methyl beta-glucosides and compared with those of two lipases and an acetyl esterase. AcXEs show regioselectivity of deactylation of methyl beta-glucosides that corresponds to their role in acetylxylan degradation, i.e. to the removal of acetyl groups from positions 2 and 3 of xylopyranosyl residues. Other esterases deactylate xylose derivatives at position 4, and glucose derivatives mainly at positions 6 and 4. Thus the AcXEs represent enzymes with a new regioselectivity of deactylation of carbohydrates. The results also allow us to draw conclusions concerning the mode of action of AcXE on partially acetylated glucuronoxylans, namely their performance on singly and doubly acetylated xylopyranosyl residues.