myosin purification

[Mr A.M. Flynn]

	Hello,
		I was wondering whether anyone has any experience in purifying
	type II myosin, (non-muscle).  I have already attempted this but,
	aparently, got a very poor recovery.  I used liver as my starting 
	material, so perhaps this isn't the best source.  Is this protein 
	prone to protease degradation?  If someone could send me a reference
	containing a purification protocol, with any pertinent points such as
	preferred choice of starting material, or whether all classes of 
	myosin will come through the purification method I would be extremely
	grateful.  Thanks very very much!