the enzyme sensitivity to isoproterenol ( 0.2 mm ) and gtp ( 1.0 mm ) decreases by 50 % after 20 min incubation , while that to guanylyl imidodiphosphate ( 0.1 mm ) , a non-hydrolyzeable analogue of gtp , is lowered by 20-25 % after 40 min .
C0018366
guanylyl imidodiphosphate
C0018353
gtp