Nitrogen Flashcards Preview

SfM > Nitrogen > Flashcards

Flashcards in Nitrogen Deck (17)
Loading flashcards...
1
Q

What is transamination?

A

Transferring amino groups between different molecules

2
Q

What are the main nitrogen containing molecules in the body?

A

Amino acids and nucleotides

-Glutamate, glutanin, aspartate, alanine

3
Q

Principles of transamination

A
  • No loss or gain of nitrogen

- Readily reversible therefore transaminases participate in AA synthesis and deviation

4
Q

What are aminotransferases reliant on?

A

Pyridoxal phosphates (PLP) cofactor - made from vitamin B

Tranfers AA groups during reaction

5
Q

What alpha-veto acid accept amino groups?

A

a-ketoglutarate

6
Q

What acts as a temporary storage of nitrogen?

A

Glutamine - can donate the amino group when required for AA biosynthesis

7
Q

What can the presence of aminotransferases indicate?

A

Prescene in plasma indicates cell damage - high ALT or AST can indicate liver disease

8
Q

Function of aspartate aminotransferase (AST)?

A

Catalyse aspartate to oxaloacetate

9
Q

Function of alanine amino aminotransferase (ALT)?

A

Catalyse alanine to pyruvate

10
Q

What does the oxidation of AA produce?

A

Lots of energy - 90% of energy requirements fuelled by AA in carnivores

Little energy in herbivores

11
Q

What 3 circumstanced to AA undergo oxidative catabolism?

A
  • Left over AA
  • Dietary AA exceed body’s protein synthesis
  • Protein in body that are broken down to supply AA for catabolism when carbs are in short (starvation, diabetes)
12
Q

Function of Trypsin and chymotrypsin

A

cut protein and larger peptides into smaller peptide in the small intestine

13
Q

Function of pepsin

A

cuts proteins into peptides in the stomach

14
Q

Function of Aminopeptidase and carboxypeptidases A and B

A

degrade peptide into amino acids in the small intestine

15
Q

What process supply AA for digestion?

A

Digestion of dietary proteins and degradation of proteins in cells

16
Q

What happens to a-ketoacids when alanine/glutamine travel to the liver?

A

They enter the Citric Acid Cycle

17
Q

What carbon atoms are formed from catabolised AA?

A
  • Acetyl-CoA
  • Pyruvate
  • a-ketoglutarate
  • Succinyl-CoA
  • Fumarate
  • Oxoloacetate