实验十二转氨作用.doc

实验十二 转氨作用
【实验目的】
1．通过实验掌握水平方向滤纸层析原理和技术
2．了解转氨作用过程。
【实验原理】
转氨基作用是由转氨酶（氨基转移酶）催化的，在这个反应中，α-氨基酸的氨基与α-***酸的***基之间交换，α-氨基酸转变成ple】
Transamination reactions are catalyzed by transaminases (aminotransferases). In this process the α-amino group is transferred from an α-amino acid to an α-Keto acid，and the α-amino acid forms an α-Keto acid. In the meantime, the α-Keto acid converts to a new amino acid. Transamination reactions are reversible. Every transamination reaction is catalyzed by a specific transaminase. Transaminases are widespread in each organ of an organism.
In this experiment, liver homogenate is under water bath with L-alanine and pyruvate, while alanine aminotransferase (ALT; also called glutamate-pyruvate transaminase,) that are important in the diagnosis of liver damage catalyzes the transfer of the amino group of alanine to α-ketoglutarate, thus yield pyruvate and glutamate. Using round paper chromatography can evaluate the existence of glutamate and can prove the transamination reaction in the tissue.
GPT
【Materials】
1. Apparatus
Petri dish; Watch-glass; A piece of chromatography filter paper; Homogenizer; Test tubes; Test tube rack; Constant temperature water boiler; Several glass capillaries; Pipette ; Sprayer; Scissors;
Pencil; Ruler.
2．Reagents
⑴ phosphoric acid buffer of pH : Prepare Na2HPO4 and NaH2PO4, then mix 81 ml of the former and 19 ml