抄録
Carboxyl groups of myosin rod were chemically modified by means of carbodiimide-mediated amidation using glycine ethyl ether as an amino donor. Mobility of the rod on urea-polyacrylamide gel electrophoresis was reduced on modification, which indicates a reduced negative charge of rod. The modification significantly promoted the filament formation of rod especially at alkaline pH. Modified rod required neither lowering pH (pH 6.0) nor Mg2+ addition for its filament formation. Amino groups of rod were also modified using the same principle of carbodiimide-mediated modification using sodium formate as a donor. This modification led to an opposite effect on the filament formation of rod. Modification rather inhibited the self-assembly of rod. Thus, it was concluded that surface negative charges of the rod play an important role in filament formation. Factors that decrease the negative charge of rod such as lowering pH, adding Mg2+, or blocking carboxyl groups led to the promotion of the filament formation similarly.
