PRODUCTION OF GUAR ALPHA-GALACTOSIDASE AND IMMUNOLOGICALLY RELATED ALPHA-GALACTOSIDASES BY HOST ORGANISMS TRANSFORMED WITH RECOMBINANT DNA METHODS

摘要

The gene encoding an alpha-galactosidase from guar seedhas been isolated and identified. It has been expressedin yeasts, e.g. Saccharomyces, Xluyveromyces andHansenula, in bacteria, e.g. Bacillus, and in plants,e.g. Nicotiana. The resulting alpha-galactosidase isable to decrease the galactose content ofgalactomannans such as guar gum by splitting off 1-6linked alpha-D-galactopyranosyl units attached to amain chain of 1-4 linked beta-mannopyranosyl units.Thus a commercially feasible process becomes availablefor producing alpha-galactosidases suitable forproviding galactomannans having improved properties,which can meet the increasing demand for good qualitypolysaccharides. It has further been demonstrated thatother alpha-galactosidases, which show a positiveimmunological cross-reaction with an antibody raisedagainst the alpha-galactosidase from guar, are alsoeffective in decreasing the galactose content ofgalactomannans such as guar.