L12 Amino acid metabolism Flashcards
Are excess amino acids stored?
No, which is the key difference betwen amino acids and other 2 types of oxidizable biomolecules (i.e. carbohydrates and fatty acids)
What is the universal amino group acceptor?
alpha-Ketoglutarate;
alpha-Ketoglutarate is one of the intermediate metabolite formed in TCA
What is the first step in the catabolism of most amino acids?
Transamination in cytosol of the liver cells
What are the main steps of amino acids catabolism?
(1) Transamination in cytosol of the liver cells
(alpha-Ketoglutarate to glutamate)
(2) Oxidative deamination of glutamate in mitochondrial matrix of liver cells
(glutamate back to alpha-Ketoglutarate)
Where is urea formed?
In liver
In non-hepatic tissues, ammonia is converted to which metabolite?
Glutamine
Give me the chemical form of amide group, amino group, and ammonia
amide group: -NH2
amino group: -NH3+
ammonia: NH4+
To remove ammonia as urea in liver, what is the first step?
Condensation of ammonia with CO2
Where does condensation of ammonia with CO2 takes place?
Mitochondrial matrix
What are the 4 enzymes involved in the Urea cycle?
(1) Ornithine transcarbamoylase
(2) Argininosuccinate synthetase
(3) Argininosucciante lyase
(4) Arginase
Phenylketonuria is a disease due to defective of which enzyme?
Defective phenylalanine hydroxylase
Give me the chemical form of Nitrate and Nitrite
Nitrate: NO3-
Nitrite: NO2-
