Enzymatic synthesis of beta-xylanase substrates: transglycosylation reactions of the beta-xylosidase from Aspergillus sp
2003 (English)In: Carbohydrate Research, ISSN 0008-6215, E-ISSN 1873-426X, Vol. 338, no 4, 313-325 p.Article in journal (Refereed) Published
A beta-D-xylosidase with molecular mass of 250 +/- 5 kDa consisting of two identical subunits was purified to homogeneity from a cultural filtrate of Aspergillus sp. The enzyme manifested high transglycosylation activity in transxylosylation with p-nitrophenyl P-D-xylopyranoside (PNP-X) as substrate, resulting in regio- and stereoselective synthesis of p-nitrophenyl (PNP) beta-(1 --> 4)-D-xylooligosaccharides with dp 2-7. All transfer products were isolated from the reaction mixtures by HPLC and their structures established by electrospray mass spectrometry and H-1 and C-13 NMR spectroscopy. The glycosides synthesised, beta-Xyl-1 --> (4-beta-Xyl-1 -->)(n)4-beta-Xyl-OC6H4NO2-p (n = 1 - 5), were tested as chromogenic substrates for family 10 beta-xylanase from Aspergillus orizae (XynA) and family 11 beta-xylanase I from Trichoderma reesei (XynT) by reversed-phase HPLC and UV-spectroscopy techniques. The action pattern of XynA against the foregoing PNP beta-(1 --> 4)-D-xylooligosaccharides differed from that of XynT in that the latter released PNP mainly from short PNP xylosides (dp 2 - 3) while the former liberated PNP from the entire set of substrates synthesised.
Place, publisher, year, edition, pages
2003. Vol. 338, no 4, 313-325 p.
beta-D-xylosidase, Aspergillus sp, transglycosylation, p-nitrophenyl beta-(1 -> 4)-D-xylooligosaccharides, beta-xylanase substrates, oligosaccharides, galactosidase, disaccharides, glucosidase, glycosides, neoglycoproteins, proteins, enzymes, awamori, oryzae
IdentifiersURN: urn:nbn:se:kth:diva-22252ISI: 000181004700003OAI: oai:DiVA.org:kth-22252DiVA: diva2:340950
QC 201005252010-08-102010-08-10Bibliographically approved