Abstract
Kinetic analysis was done on chitinase E3 (EC 3.2.1.14) from yam, Dioscorea opposita Thunb, using both series of N-acetylchitooligosaccharides (GlcNAc„, /i = 2 to 6) and β-nitrophenyl N- acetylchitooligosaccharides (pNp-GlcN Ac„, w= 1 to 5) as substrates. The enzyme cleaved GlcNAc3 to GlcNAc plus GlcNAc2, G1cNAc4 to two molecules of GlcNAc2, GlcNAc5 to GlcNAc2 plus GlcNAc3, and GlcNAc6 by three ways to GlcNAc plus GlcNAc5 (32 %), GlcNAc2 plus GlcNAc4 (42 %) and two molecules of GlcNAc3 (26%). The speed of the reaction was observed in the following order, GlcN Ac4 > GlcN Ac5 > GlcNAc6 > GlcN Ac3. Stronger substrate inhibition was observed in the longer chain substrates. The reactions of pNp-GlcNAcw (N = 1 to 5) were similar to those of GlcNAc„ (N = 2 to 6), respectively. The cleavage sites of pNp-GlcNAc2 and pNp-GlcNAc3 were the second β-1,4-linkages from the reducing end side, and the main cleavage sites of pNp-GlcNAc4 and pNp-GlcNAc5 were the third linkages. β-Nitrophenol was not released from all β-nitr...
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
