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Flashcards in Proteins Deck (28):
1

Primary sequence?

Sequence of amino acids in a polypeptide

2

Secondary structure?

Spatial arrangement of R groups that are near each other in a sequence

3

What are the types of secondary structure?

- Alpha helices
- Beta sheets
- Turns

4

How are alpha helices stabilised?

H bonds between NH and CO groups in the next "spin" of the helix

5

What stabilises beta sheets?

H bonds between amide groups of sheets running parallel

6

Tertiary structure?

Interactions between R groups that are far away from each other in the sequence

7

What stabilises tertiary structure?

- Van der waals
- Ionic
- H bonds
- Disulphide bridges
- Hydrophobic interactions

8

What residue forms disulphide bridges?

Two cysteine residues

9

Where can disulphide bridges form?

- Intermolecularly
- Between two different polypeptides

10

Quaternary structures?

- Spatial arrangement of polypeptide chains in multi chain proteins

11

What structure remains in tact after denaturation?

Primary

12

What does denaturation effect?

- Reduces solubility
- Loses biological activity
- Easier to digest

13

What is glycosylation?

Post translational modification where a sugar is added via an amino acid

14

What is one example of a glycoprotein?

Immunoglobulins

15

Where does glycolysation occur in the cell?

- ER
- Golgi

16

Function of lipoproteins?

Transport through the blood

17

What do lipoproteins transport in the blood?

- Water
- Fat
- Cholesterol

18

What are metalloproteins?

- Protein with a bound metal ion

19

Function of metalloproteins?

- Enzymes
- Signalling
- Transport

20

What is co-operative binding using haemoglobin as an example

- O2 binds to one subunit
- Conformational change in other subunits increases their affinity for O2

21

What causes sickle cell anaemia?

HYDROPHILIC glutamic acid substituted by HYDROPHOBIC Valine

22

What is the structure of collagen?

Coiled polypeptides in a helix structure

23

What is scurvy caused by?

Vitamin C deficiency

24

What does a vitamin C deficiency cause?

Formation of weaker collagen

25

Effects of osteogenesis imperfecta?

- Collagen can't form the tight coil
- Secondary and tertiary structure lost so brittle collagen produced

26

What happens if a mutation causes no LDL receptors to reach the cell membrane?

- No receptors
- LDL not released

27

What disease can result from the LDL receptor mutation?

Familial hypercholesterolemia

28

What does FH result in?

Early CVD