kinetic parameters indicated that the gamma subunit binds the substrates mgatp and phosphorylase b as well as the holoenzyme with a km ( mgatp ) of 98 microm and a km ( phosphorylase b ) of 80 microm at ph 8.2 , but maximal velocities are significantly lower than the holoenzyme 's .
C0031711
phosphorylase b
C0017916
phosphorylase