lecture 17 - red blood cells and plasma proteins Flashcards Preview

oneoseven > lecture 17 - red blood cells and plasma proteins > Flashcards

Flashcards in lecture 17 - red blood cells and plasma proteins Deck (27):
1

albumin knowledge critical for...

drug design. must bind drug to "drive" it around the body

2

B-cells produce?

each make antibodies specific to an antigen and make membrane-bound versions, specific to the same antigen

3

order the following from smallest to largest (#AA)
- serum albumin
- haemoglobin
- Immunoglobulin
- lysozyme

smallest
- lysozyme ~129 amino acids
- haemoglobin ~574 amino acids
- serum albumin ~585 amino acids
- immunoglobulin ~1294 amino acids
Largest

4

serum albumin concentration

Concentration of 35mg/mL in serum. Main component of plasma proteins.

5

structure of antibody

- y-shaped
- 2 heavy amino acid chains, 2 light amino acid chains
- built from 12 immunoglobulin (IgG) domains
- chains held by disulphide bridges (cystine responsible)

6

secondary structure of haemoglobin

alpha helical

7

concentration of haemoglobin in blood (overall)

150mg/mL

8

where are immunoglobulins made?

B-lymphocytes (white blood cell) [aka B-cells]

9

how many O2 molecule carried by haemoglobin?

= 4
there are four chains each with their own heme group which binds 1 O2 molecule to the iron.

10

what is the same and what changes in antibodies with different specificities?

- variable region changes (different arangemnt of the emd 2 IgG domains)
- constant region stays the same

11

who discovered haemoglobin and how?

Max Perutz, by protein crystallography

12

erythrocytes made in?

reticulocytes (myeloid stem cells in the marrow)

13

albumin structure

single amino acid chain. All α-helices (secondary structure)

14

albumin function

carrier for small insoluble molecules (lipids, hormones, steroids, man-made drugs)

15

diameter, shape and cellular components/contents of RBC?

- 8μm
- biconcave disc
- no nucleus, no organelles
- heaps and heaps of haemoglobin (340mg/mL)

16

how is the antigen recognised?

by its EPITOPE binding to the antigen-binding site

17

sickle cell anaemia vs. malaria

carrying 1 copy of the mutated gene causes resistance to malaria.

18

blood type determined by?

blood group antigens present on membrane of erythrocytes

19

role of immunoglobulin in immune system? (analogy)

prior knowledge - can bind to all sorts of bacteria/virus. millions of different binding specificities

20

hematocrit level?

volume of red blood cells: volume of blood. Higher in males because testosterone increases EPO = more RBC production.

21

lifetime of red blood cells?

120 days

22

sickle cell anaemia mutation cause? results?

point mutation of single nucleotide A to T in haemoglobin sequence. Results in what should be GIutamic acid, being replaced with Valine. Protein produced forms fibres which disfigure erythrocytes into the sickle shape.

23

concentration of immunoglobulin/antibodies in serum

20mg/mL

24

immunoglobulin domain?

- small length of amino acids folded into c-shape held by disulphide bridge
- All β-pleated sheets.

25

proteins recap

linear polymers of amino acids joined by peptide bonds

26

structure of haemoglobin

- 2 amino acid sequences (α and β not secondary structures)
- 4 subunits (ααββ)
- 4 heme groups (1 per chain)
- Alpha helical secondary structure

27

how many of the domains are variable?

4 (2 on each end)