Roles of active site tryptophans in substrate binding and catalysis by -1,3 galactosyltransferase
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چکیده
منابع مشابه
Functional roles in S-adenosyl-L-methionine binding and catalysis for active site residues of the thiostrepton resistance methyltransferase.
Resistance to the antibiotic thiostrepton, in producing Streptomycetes, is conferred by the S-adenosyl-L-methionine (SAM)-dependent SPOUT methyltransferase Tsr. For this and related enzymes, the roles of active site amino acids have been inadequately described. Herein, we have probed SAM interactions in the Tsr active site by investigating the catalytic activity and the thermodynamics of SAM bi...
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Mammalian phenylalanine hydroxylase (PAH) is a key enzyme in l-phenylalanine (l-Phe) metabolism and is active as a homotetramer. Biochemical and biophysical work has demonstrated that it cycles between two states with a variably low and a high activity, and that the substrate l-Phe is the key player in this transition. X-ray structures of the catalytic domain have shown mobility of a partially ...
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BACKGROUND The proteasome is a multicatalytic protease complex responsible for most cytosolic protein breakdown. The complex has several distinct proteolytic activities that are defined by the preference of each for the carboxyterminal (P1) amino acid residue. Although mutational studies in yeast have begun to define substrate specificities of individual catalytically active beta subunits, litt...
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ژورنال
عنوان ژورنال: Glycobiology
سال: 2004
ISSN: 1460-2423
DOI: 10.1093/glycob/cwh119