Abstract
Two chitinase isoforms, designated GBC-a and GBC-b, were purified from the bulbs of gladiolus (Gladiolus gandavensis) using CM-cellulose column chromatography followed by Butyl-Toyopearl 650M hydrophobic column chromatography, gel filtration on Sephadex G-75, and Mono-S FPLC. GBC-a and GBC-b are weakly acidic and weakly basic proteins with molecular masses of 30 kDa, and isoelectric points of 6.0 and 7.5, respectively. GBC-a and GBC-b were found to be homologous proteins with similar amino acid compositions and N-terminal sequences. The number of half-cystine residues in GBC-a and GBC-b was only one each, which is much lower than those of plant class I (15-17 Cys residues/mol), class II (5-8 Cys residues/mol), and class III (6 Cys residues/mol) chitinases. The N-terminal sequences of GBC-a and GBC-b were completely different from those of plant three classes of chitinases. The optimal pHs of these chitinases toward glycolchitin were pH 5. GBC-a hydrolyzed (GlcNAc)6 into (GlcNAc)2, (GlcNAc)3 and (GlcNAc)4, and (GlcNAc)5, into (GlcNAc)2, and (GlcNAc)3.
Original language | English |
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Pages (from-to) | 2140-2142 |
Number of pages | 3 |
Journal | Bioscience, Biotechnology and Biochemistry |
Volume | 61 |
Issue number | 12 |
DOIs | |
Publication status | Published - Jan 1997 |
All Science Journal Classification (ASJC) codes
- Biotechnology
- Analytical Chemistry
- Biochemistry
- Applied Microbiology and Biotechnology
- Molecular Biology
- Organic Chemistry