click below
click below
Normal Size Small Size show me how
Biochem Lecture 4
Review of Amino Acid Metabolism
Question | Answer |
---|---|
3 sources of amino acids are: | 1. Body Protein 2. Dietary Protein 3. Synthesis of non-essential amino acids |
When does our body use protein as a source of energy? | When we have excess protein or a lack of Carbs and Lipids. |
List the essential amino acids: | Phe, Val, Thr, Ile, Met, His, Arg, Lys, Leu |
What amino acids are formed by transamination reactions? | Alanine, aspartate, and glutamate |
Alanine is formed from ______ using the enzyme ______. | Pyruvate; ALT (with glutamate as a cofactor) |
Aspartate is formed from ______ using the enzyme ________. | Oxaloacetate; AST |
Asparagine is formed from _______. | Aspartate |
Glutamine is formed from ________. | Glutamate |
In the formation of asparagine, _________ is the amide donor. | Glutamine |
Proline is formed from _______. | Glutamate |
Serine is formed from ________. | 3-phosphoglycerate (intermediate of glycolysis)or glycine |
Glycine is formed from _________. | Serine |
Cysteine is formed from _______. | Serine and Methionine |
Tyrosine is formed from _________. | Phenylalanine |
PKU is a disease that leads to CNS problems and pigmentation deficiencies and is caused by_____. | The absense of phenylalanine hydroxylase; the enzyme that catalyzes the conversion of phenylalanine to tyrosine. |
Homocystinuria is a disease that causes premature vascular disease and mental defects and is caused by ________. | An absence of the enzyme cystathionine synthase which catalyzes the creation of Cystine. |
3 sources of amino acids are: | 1. Body Protein 2. Dietary Protein 3. Synthesis of non-essential amino acids |
When does our body use protein as a source of energy? | When we have excess protein or a lack of Carbs and Lipids. |
List the essential amino acids: | Phe, Val, Thr, Ile, Met, His, Arg, Lys, Leu |
What amino acids are formed by transamination reactions? | Alanine, aspartate, and glutamate |
Alanine is formed from ______ using the enzyme ______. | Pyruvate; ALT (with glutamate as a cofactor) |
Aspartate is formed from ______ using the enzyme ________. | Oxaloacetate; AST |
Asparagine is formed from _______. | Aspartate |
Glutamine is formed from ________. | Glutamate |
In the formation of asparagine, _________ is the amide donor. | Glutamine |
Proline is formed from _______. | Glutamate |
Serine is formed from ________. | 3-phosphoglycerate (intermediate of glycolysis)or glycine |
Glycine is formed from _________. | Serine |
Cysteine is formed from _______. | Serine and Methionine |
Tyrosine is formed from _________. | Phenylalanine |
PKU is a disease that leads to CNS problems and pigmentation deficiencies and is caused by_____. | The absense of phenylalanine hydroxylase; the enzyme that catalyzes the conversion of phenylalanine to tyrosine. |
Homocystinuria is a disease that causes premature vascular disease and mental defects and is caused by ________. | An absence of the enzyme cystathionine synthase which catalyzes the creation of Cystine. |
Ketogenic amino acids yield ______. | acetyl CoA or acetoacetate |
Glucogenic amino acids yield ______. | Pyruvate or Kreb cycle intermediates |
Aminotransferases (transaminases) depend on | Vitamin b6 |
The 2 most important aminotransferases are: | ALT and AST |
Alanine amino transferase (ALT) changes alanine and a-ketoglutarate into _________ | pyruvate and glutamate |
Aspartate amino transferase (AST) changes glutamate and a-ketoglutarate into ________ | Aspartate and oxaloacetate |
_________ are the sources of urea nitrogen. | Aspartate and ammonia |
________ releases free ammonia for urea synthesis. | Oxidative deamination reaction of glutmatate. |
The oxidative deamination reaction of glutamate releases what products? | a-ketoglutarate + NH3 (ammonia) |
What enzyme is involved in the oxidative deamination of glutamate? | glutamate dehydrogenase |
Where is arginase found and what does it do? | Arginase is only found in the liver; It converts arginine to urea in the Urea cycle. |
What is the overall reaction of the Urea Cycle? | Aspartate + NH3 + CO2 + 3 ATP ----> Urea + Fumurate + 2 ADP + AMP + 2 Pi + PPi |
The first two reactions of the Urea cycle occur in the ________, and the remaining three take place in the __________. | Mitochondrial Matrix; Cytosol |