二氨基酸的分解 ☆脱氨基（Deamination) 氧化脱氨基（谷氨酸脱氢酶） 转氨酶 联合脱氨基 ☆脱羧基(Decarboxylase) ☆氨的去向：鸟氨酸循环(Urea Cycle) 谷氨酰胺的合成 ☆碳骨架的去向(Metabolic Fate of Carbon Skeleton of Amino Acids)
二 氨基酸的分解 ☆脱氨基 ( Deamination) 氧化脱氨基(谷氨酸脱氢酶) 转氨酶 联合脱氨基 ☆脱羧基 (Decarboxylase) ☆氨的去向：鸟氨酸循环 (Urea Cycle) 谷氨酰胺的合成 ☆碳骨架的去向 (Metabolic Fate of Carbon Skeleton of Amino Acids)
(一)氨基酸的主要脱氨基方式 ☆氧化脱氨基 ☆转氨基作用 Aspartate+o-ketoglutarate-oxaloacetate+glutamate Alanine +a-ketoglutarate-pyruvate +glutamate ☆联合脱氨基；氨基酸把氨基转给a-酮 戊二酸转变成谷氨酸，然后在谷氨酸脱氢酶的作用 下脱掉氨基
☆氧化脱氨基 ☆转氨基作用 ☆联合脱氨基；氨基酸把氨基转给a-酮 戊二酸转变成谷氨酸，然后在谷氨酸脱氢酶的作用 下脱掉氨基。 （一）氨基酸的主要脱氨基方式
Alpha-Amino Groups Are Converted into Ammonium lons by the Oxidative Deamination of Glutamate The a-amino group of many amino acids is transferred to a-ketoglutarate to form glutamate, which is then oxidatively deaminated to yield ammonium ion (NH4 +) →NH C0 H N Amino acid Glutamate
Alpha-Amino Groups Are Converted into Ammonium Ions by the Oxidative Deamination of Glutamate • The a-amino group of many amino acids is transferred to a-ketoglutarate to form glutamate, which is then oxidatively deaminated to yield ammonium ion (NH4 +)
Aminotransferases catalyze the transfer of an a-amino group from an a-amino acid to an a-ketoacid. These enzymes,also called transaminases,generally funnel a-amino groups from a variety of amino acids to a-keto-glutarate for conversion into NH4+. Aminotransferase -00 R 00C R 00d Aspartate a-ketoglutarate==oxaloacetate glutamate Alanine o-ketoglutarate -pyruvate glutamate NAD (or N )(
Aminotransferases catalyze the transfer of an a-amino group from an a-amino acid to an a-ketoacid. • These enzymes, also called transaminases, generally funnel a-amino groups from a variety of amino acids to a-keto-glutarate for conversion into NH4 +
a-Amino acid NAD+a-ketoacid NH NADH +H+ (or NADP+) (or NADPH) a-Amino acid a-Ketoglutarate NADH+NH4→ NH Urea @-Ketoacid+ Glutamate NAD++H2O