Barley Malt alpha-Glucosidase. II. Studies on the Substrate Specificity.
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چکیده
منابع مشابه
Purification, enzymatic characterization, and nucleotide sequence of a high-isoelectric-point alpha-glucosidase from barley malt.
High-isoelectric-point (pI) alpha-glucosidase was purified 7, 300-fold from an extract of barley (Hordeum vulgare) malt by ammonium sulfate fractionation, ion-exchange, and butyl-Sepharose chromatography. The enzyme had high activity toward maltose (k(cat) = 25 s(-1)), with an optimum at pH 4.5, and catalyzed the hydrolysis by a retaining mechanism, as shown by nuclear magnetic resonance. Acarb...
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A comparative chromatography of polyphenoloxidase isolated from barley, steeped barley, and green malt was made. It consisted ofextraction, precipitation, ion-exchange chromatography, gel filtration, and electrofocusing. Polyphenoloxidase was resolved into a high-molecularweight enzyme and a low-molecular-weight one. The proportion of the two enzymes underwent variations during malting. An incr...
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1. The substrate specificity of the enzyme protochlorophyllide reductase in barley (Hordeum vulgare) etioplasts was investigated. 2. It was shown that naturally occurring esterified protochlorophyllide and chemically prepared protochlorophyllide methyl ester are not substrates for the enzyme, suggesting an important role for the C-7 carboxylic acid group in binding of the porphyrin to the enzym...
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ژورنال
عنوان ژورنال: Acta Chemica Scandinavica
سال: 1963
ISSN: 0904-213X
DOI: 10.3891/acta.chem.scand.17-2471