Abstract
An isolation procedure for preparing gram quantities of a previously undescribed protein from muscle is presented. The protein amounts to over 2% of the sarcoplasmic proteins of pig longissimus dorsi muscle, but does not correspond to any glycolytic enzyme, not to any of several other enzymes that have been tested for. The protein is isoelectric between pH8.5 and 9.0, has mol.wt. 34500[plus or minus] 500 and has E1%281m[mu] 20.7. The identities of nearly all the major protein bands obtained in electrophoresis on starch gel of pig longissimus dorsi muscle sarcoplasm have been established.