SUMMARY: Xanthan lyases, cleaving the terminal β-mannosidic linkage of the side-chain of the exopolysaccharide xanthan from , have been obtained from several sources. These include a species, a species and a mixed culture. The lyases were initially associated with endo-β-glucanases cleaving the main chain of xanthan. Partial purification of the enzymes was achieved and the preparation was separated by FPLC into material free of endoglucanase and glycosidase activities. The lyase was active on polysaccharides with and without acetate and pyruvate. The optimal size of the substrate appeared to be in the range of degree of polymerization (DP) 25–35, i.e. 5–7 repeat units of the polysaccharide. No activity was found against xanthan modified by reduction of the carboxyl groups or by the addition of amine or hydroxyethyl groups. The combined action of the lyase and the endoglucanase yielded a series of oligosaccharides, each with a side-chain terminating in an unsaturated uronic acid and containing the molar ratio of -glucose to -mannose, 2:1.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error