Action of Dinitrophenyl Amino Acids on Skeletal Muscle Proteins II. Absorption of Bis-Dinitrophenyl-Lysine By Light and Heavy Meromyosins and by Light Meromyosin Fraction I

Abstract

The quantity of bis(2,4-dinitrophenyl)-L-Iysine (abbreviation bis-DNP-Iysine) absorbed at 5°C by myosin and meromyosins of rabbit skeletal muscle was estimated in phosphate buffer (pH 7, ionic strength 0·5) by two methods, one based on equilibrium dialysis, the other on high-speed centrifugation. According to both methods, heavy meromyosin absorbed more of the reagent than did the same weight of the parent myosin; light meromyosin absorbed less, and light meromyosin fraction I absorbed less still. There were, however, relatively large quantitative differences between the two methods, possibly because of an effect of the slightly different conditions of treatment.