ELECTRON-MICROSCOPY OF THERMAL AGGREGATION OF MYOSIN

The morphological changes of myosin molecules occurring on thermal treatment at 40°C in 0.5 M KC1 at pH 6.0 were observed under an electron microscope. Most myosin molecules were in the monomeric state in the unheated control, although some were associated through their head regions, forming oligomers. Myosin monomers decreased upon heating, while myosin molecules aggregated to form an oligomer, in which the myosin heads were tightly associated, forming a clump, the tails of the myosin molecules extending radially from the clump. Such an oligomer was shaped a daisy wheel. The tails of myosin molecules slightly shortened upon heating. © 1990 Copyright, 1990 by the Journal of Biochemistry.