Harpers

+H 2 NHNHCNH 2NHCHCH 2CH 2 + H3 N COO –CH 2C+NH 32GlycineCOO –L-ArginineCHNNCreatinineCOCH 3CH 2Figure 31–6.(Kidney)ARGININE-GLYCINETRANSAMIDINASEOrnithine+H 2 NS-AdenosylmethionineS-AdenosylhomocysteineCNH 2HN CH 2 COO –Glycocyamine(guanidoacetate)(Liver)ATPGUANIDOACETATEMETHYLTRANSFERASEADPNONENZYMATICIN MUSCLENH PP i + H 2 O CH 3HN CN CH 2 COO –Biosynthesis and metabolism of creatine and creatinine.Creatine phosphateCOO –L-GLUTAMATEDECARBOXYLASEC NH 3+CH 2CH 2COO –PLPL-GlutamateCO 2CH 2 OHCH 2+ H3 N CH 2 CH 2 CH 2 COO – CH 2γ-AminobutyrateCOO –[O]Hγ-HydroxybutyratePLPNAD +LACTATEDEHYDROGENASE+[NH 4 ] NADH + H +CO 2OCCH 2Hα-KATRANSAMINASEα-AACOO –CCH 2CH 2OCOO –α-KetoglutarateSUCCINICSEMIALDEHYDEDEHYDROGENASECOO –CH 2CH 2CH 2H 2 O NAD + NADH + H +COO –COO –Succinate semialdehydeSuccinateFigure 31–7. Metabolism of γ-aminobutyrate. (α-KA, α-keto acids; α-AA, α-amino acids; PLP, pyridoxalphosphate.)268