Amino acid degradation Amino acids are termed glucogenic if their carbon skeletons can give rise to the net synthesis of glucose and ketogenic of they can give rise to ketone bodies. Some amino acids give rise to more than one intermediate and these lead to the synthesis of glucose as will as ketone bodies. Thus these amino acids are both glucogenic and ketogenic
Amino acid degradation • Amino acids are termed glucogenic if their carbon skeletons can give rise to the net synthesis of glucose ,and ketogenic of they can give rise to ketone bodies. Some amino acids give rise to more than one intermediate and these lead to the synthesis of glucose as will as ketone bodies. Thus these amino acids are both glucogenic and ketogenic
容 pathway Ala Cys Gly be Th Trp Glucose Leu Pyruvate Leu Phe Trp Tr Phosphoenol- cetyl CoA= Acetoacetyl COA Asn Oxaloacetate Ketone bodies CIRIC ACID CYCLE Fumarate Citrate [ Succinyl COA a-Ketoglutarate c Pro Fig. 2. Fates of the amino acid carbon skeletons
pathway
Transamination The a-amino group of most amino acids is transferred to a-ketoglutarate to form glutamate and the corresponding a-keto acid a-amino acid a-ketoglutarate -keto acid+ glutamate Enzyme: transaminases
Transamination • The α-amino group of most amino acids is transferred to α-ketoglutarate to form glutamate and the corresponding α-keto acid • α-amino acid + α-ketoglutarate α-keto acid + glutamate • Enzyme: transaminases
Aminotansferase coo COo Coo HSN-C-H Coo PLP CH HaN-C-H CH+ C-o aminotransferase C R CHg R coo Coo aKetoglutarate L-Amino acid L-Glutamate c-Keto acid COo COO C-O cOo HaN C PLP CHe +H N-C-H CH alanine aminotransferase CHg CH3 CH COo a-Ketoglutarate L-Alanine L-Glutamate Pyruvate
Aminotansferase
Vitamine b6 C2 m00-2-090)0H0-2-0
Vitamine B6