supernatant fractions ( 300,000 x g , 60 min ) from homogenates of rat liver , heart , and skeletal muscle , dog liver , and rabbit liver prepared without detergent in the homogenization medium ( referred to as s300 ) are shown to contain an activity that restores mg2+-dependent fluoride- and guanine nucleotide-stimulated cyclizing activity to the adenylate cyclase system [ atp pyrophosphate-lyase ( cyclizing ) ; ec 4.6.1.1 ] in cyc- s49 murine lymphoma cell membranes .
C1382029
atp
C0007603
cell