TAILIEUCHUNG - Báo cáo khoa học: Mode of action of glycoside hydrolase family 5 glucuronoxylan xylanohydrolase from Erwinia chrysanthemi

The mode of action of xylanase A from a phytopathogenic bacterium, Erwinia chrysanthemi, classified in glycoside hydrolase family 5, was investi-gated on xylooligosaccharides and polysaccharides using TLC, MALDI-TOF MS and enzyme treatment with exoglycosidases. | ễFEBS Journal Mode of action of glycoside hydrolase family 5 glucuronoxylan xylanohydrolase from Erwinia chrysanthemi Maria Vrsanska Katarina Kolenova Vladimir Puchart and Peter Biely Institute of Chemistry Slovak Academy of Sciences Bratislava Slovakia Keywords Erwinia chrysanthemi GH5 glucuronoxylan-specific xylanase mode of action Correspondence M. Vrsanska Institute of Chemistry Slovak Academy of Sciences Dubravska cesta 9 SK-845 38 Bratislava Slovakia Fax 421 2 5941 0222 Tel 421 2 5941 0224 E-mail chemmvsa@ Received 21 November 2006 revised 18 January 2007 accepted 19 January 2007 doi The mode of action of xylanase A from a phytopathogenic bacterium Erwinia chrysanthemi classified in glycoside hydrolase family 5 was investigated on xylooligosaccharides and polysaccharides using TLC MALDI-TOF MS and enzyme treatment with exoglycosidases. The hydrolytic action of xylanase A was found to be absolutely dependent on the presence of 4-ơ-methyl-D-glucuronosyl MeGlcA side residues in both oligosaccharides and polysaccharides. Neutral linear b-1 4-xylooligosaccharides and esterified aldouronic acids were resistant towards enzymatic action. Aldouronic acids of the structure MeGlcA3Xyl3 aldotetraouronic acid MeGlcA3Xyl4 aldopentaouronic acid and MeGlcA3Xyl5 aldohexa-ouronic acid were cleaved with the enzyme to give xylose from the reducing end and products shorter by one xylopyranosyl residue MeG-lcA2Xyl2 MeGlcA2Xyl3 and MeGlcA2Xyl4. As a rule the enzyme attacked the second glycosidic linkage following the MeGlcA branch towards the reducing end. Depending on the distribution of MeGlcA residues on the glucuronoxylan main chain the enzyme generated series of shorter and longer aldouronic acids of backbone polymerization degree 3-14 in which the MeGlcA is linked exclusively to the second xylopyranosyl residue from the reducing end. Upon incubation with b-xylosidase all acidic hydrolysis products of acidic oligosaccharides and .

• Báo cáo khoa học
• Report medicine
• traditional medicine
• scientific reports
• Crystal structure
• medical analysis
• biochemical studies
• medical knowledge
• medical research
• analysis of cytoplasmic
• oxidation
• bacteria
• hemoglobin
• medicine
• cell proliferation
• breast cancer
• chemical reaction
• gastric cancer
• hormone medicine
• tumor cells
• environmental medicine