Barley beta-galactosidase: structure, function, heterogeneity, and gene origin.

D Triantafillidou; J G Georgatsos

doi:10.1023/a:1013369129751

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Barley beta-galactosidase: structure, function, heterogeneity, and gene origin.

D Triantafillidou·J G Georgatsos

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Abstract

Barley (Hordeum vulgare) beta-galactosidase is composed of a large (45 kDa) and a small (33 kDa) polypeptide. N-terminal sequencing of the polypeptides and antibody reactivity data place the barley enzyme and heterodimeric plant beta-galactosidases from jack bean, maize, and wheat in family 35 of the glycosyl hydrolases. Sequence analysis indicates the existence of a subfamily of genes coding for polypeptide precursors that are cleaved to produce the two subunits in heterodimeric beta-galactosidases. The heterogeneity of the barley holoenzyme is related, but not restricted, to the N-glycosylation of the small polypeptide. Both polypeptides are essential for the catalytic activity of the enzyme.

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Amino Acid Sequence Antibodies Electrophoresis, Polyacrylamide Gel Evolution, Molecular Glycosylation Hordeum Molecular Sequence Data Sequence Alignment Sequence Analysis, Protein Species Specificity beta-Galactosidase Journal Article Research Support, Non-U.S. Gov't

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D Triantafillidou, J G Georgatsos. 2001. Barley beta-galactosidase: structure, function, heterogeneity, and gene origin.. https://doi.org/10.1023/a%3A1013369129751

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