Abstract
β-Connectin, a 2, 100 kDa fragment of connectin, was extracted with 0.1M phosphate buffer at pH 6.6 and purified on a Bio-Gel A 50m gel filtration from carp skeletal myofibrils. The isolated connectin was in the native state judging from the fact that it enhanced aggregation of both myosin and actin filaments and appreciably elevated actomyosin Mg-ATPase activity.
The thermal denaturation of connectin was measured in 0.1M and 0.6M KCl solutions of neutral pH by means of turbidity. Increase in turbidity was observed at 40°C and occurredmarkedly above 50°C. A physiological concentration of Ca2+ and Mg2+ did not affect turbidity. Theloss of interaction of connectin with myosin was caused by the denaturation of myosin at lower temperatures rather than that of connectin.
