Protein and Amino Acid Metabolism Flashcards Preview

Phase 1 - S2 Metabolism, Endocrinology, Haematology > Protein and Amino Acid Metabolism > Flashcards

Flashcards in Protein and Amino Acid Metabolism Deck (56)
Loading flashcards...
1

what are the major nitrogen containing components in the body

- amino acids
- proteins
- nitrogenous bases
- creatine

2

what is creatinine

break down product of creatine and creatine phosphate

3

what is the level of creatinine in the urine proportional to

muscle mass

4

what is creatinine used as an indicator for

renal function (raised levels on damage to nephrons)

5

when is it normal to have a large nitrogen intake than output

during pregnancy or rapid growth

6

when is it normal to have a larger nitrogen output than intake

it is never normal - only occurs in trauma, infection and malnutrition

7

what is the main method for nitrogen output

loss of nitrogen through the faeces and urine

8

what is proteolysis

production of amino acids from proteins

9

what happens to amino acids in the liver

they are broken down into an amino group and the carbon skeleton

10

what are glucogenic amino acids

ones that can undergo gluconeogenesis to give energy e.g. glycine

11

what are ketogenic amino acids

ones that produce ketone bodies to give energy e.g. lysine and leucine

12

what determines whether an amino acid is glucogenic or ketogenic

their side chains

13

give an example of an amino acid that is both glucogenic and ketogenic

tyrosine

14

what effect does insulin have on protein synthesis

increases

15

what affect does glucocorticoids have on protein synthesis

decreases it

16

what is cushing's syndrome

excessive breakdown of protein occurs weakening the skin structure leading to striae formation

17

what are non essential amino acids synthesised from

- intermediates of glycolysis
- pentose phosphate pathway
- krebs cycle

18

what is transamination

the conversion on one amino acid to another by swapping an amine group of an amino acid with an oxygen of a keto acid

19

what does tyrosine produce

-catecholamines
- melanin
-thyroid hormones

20

what does cysteine produce

- glutathione

21

what does histidine produce

histamine

22

what does arginine produce

nitric oxide

23

what does glycine produce

- haem
- creatine
- purines
- glutathiones

24

what are the 2 methods for removal of nitrogen from amino acids

- transamination
- deamination

25

outline transamination to produce glutamate

alpha ketogluatarate is converted into glutamate and an amino acid into a keto acid by an aminotransferase enzyme

26

outline transamination to produce aspartate

a glutamate is converted into a keto acid and oxaloacetate is converted into aspartate by aspartate aminotransferase

27

what coenzymes do aminotransferase enzymes use

coenzymes requiring vitamin B6

28

what does alanine aminotransferase do

converts alanine to glutamate

29

what can levels of aminotransferase enzymes be used to test

liver function tests

30

what do high levels of aminotransferase enzymes mean

liver cellular necrosis from toxins, viral hepatitis