guanylate cyclase ( gtp pyrophosphate-lyase ( cyclizing ) ; ec 4.6.1.2 ) , in the crude synaptosomal soluble ( p ( 2 ) -soluble ) fraction obtained by hypo-osmotic treatment and subsequent centrifugation of crude synaptosomal ( p ( 2 ) ) fraction from the rat brain , showed a significantly high activity when assayed in the presence of high concentration of mn ( 2+ ) .
C0018358
guanylate cyclase
C0024188
lyase