抄録
Interactions of methyl 6-deoxy-N-acetyl-α-D-glucosaminide (α-Me-6-deoxy-NAG), acetamides, and alcohols with hen egg-white lysozyme [EC 3. 2. 1. 17] were studied by means of the changes in the tryptophyl circular dichroic (CD) bands at 295 and 305nm. The effects on the CD spectrum of lysozyme and the binding energy of α-Me-6-deoxy-NAG were essentially the same as those of methyl α-D-glucosaminide (α-Me-NAG). This indicates that the hydrogen bond between O (6) of β-NAG, α-Me-NAG, or β-Me-NAG and the indole NH of Trp 62 is not important for the binding of these saccharides. Acetamides as well as alcohols were shown to interact with lysozyme at the substrate-binding subsite C. The binding of alcohols was stronger than that of acetamides for compounds having the same alkyl chain length. Ethanol had the largest binding constant among the alcohols studied. The binding constants of N-2-hydroxyalkylacetamides were larger than those of the corresponding N-alkylacetamides.
