Syntheses and testing of substrates and mechanism-based inactivators for xylanases.
The syntheses of the 2,5- and 3,4-dinitrophenyl beta-xylobiosides by two separate routes are described, as well as the syntheses of the 2,4-dinitrophenyl beta-glycosides of 2-chloro-2-deoxy-xylobiose and 2-deoxy-2-fluoro-xylobiose. Both the 3,4- and 2,5-dinitrophenyl beta-xylobiosides proved to be good substrates for the Bacillus subtilis xylanase, with kcat/Km values of 1.0 and 34.4 mM-1 s-1, respectively. Excellent time-dependent inactivation of the exoxylanase/glucanase from Cellulomonas fimi was provided by 2,4-dinitrophenyl 2-deoxy-2-fluoro-beta-xylobioside, according to inactivation parameters of ki = 0.057 min-1 and Ki = 0.0035 mM.
Ziser
L
L
Department of Chemistry, University of British Columbia, Vancouver, Canada.
Setyawati
I
I
Withers
S G
SG
D002240:Carbohydrate Sequence; D004136:Dinitrobenzenes / Q000138:chemical synthesis; D004187:Disaccharides / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D006219:Halogens; D006868:Hydrolysis; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D015394:Molecular Structure; D043325:Xylan Endo-1,3-beta-Xylosidase; D014995:Xylosidases / Q000032:analysis / Q000037:antagonists & inhibitors* / Q000378:metabolism*
D004136:Dinitrobenzenes; D004187:Disaccharides; D004791:Enzyme Inhibitors; D006219:Halogens; D014995:Xylosidases; D043325:Xylan Endo-1,3-beta-Xylosidase; C004173:xylobiose