MGD S1 - Amino acids, Proteins and Protein folding Flashcards Preview

ESA1 Callum's cards > MGD S1 - Amino acids, Proteins and Protein folding > Flashcards

Flashcards in MGD S1 - Amino acids, Proteins and Protein folding Deck (32):
1

Golgi body is important for what?

Export of proteins
Detoxification reactions

2

Cytoplasm is involved in?

Metabolism of carbohydrates, amino acids and lipids
Fatty acid synthesis

3

Function of lysosomes?

Cellular digestion

4

Mitochondria perform what function?

ATP synthesis

5

Endoplasmic reticulum functions?

Export of proteins
Membrane synthesis
Detoxification reactions
Protein synthesis (rER)

6

Nucleus does what now?

DNA synthesis and repair

7

What's the function of the Nucleolus?

RNA processing and ribosome assembly

8

Plasma membrane is for?

Cell morphology and movement

9

What's the function of Ribosomes?

Protein synthesis

10

Is it hydrophobic or hydrophillic molecules that can pass through a cell membrane unassisted?

Hydrophobic

11

How does a prokaryote differ from eukaryotes?

No membrane bound organelles
One circular strand of DNA + plasmids
Flagella
Smaller ribosomes (70s not 80s)
Bacteria only, can't form multicellular organisms

12

pH refers to what?

Measurement of the concentration of H+ ions in a solution.

13

What's a buffer?

A mix of an acid and its conjugate base that resists change in pH

14

What is the isoelectric point (pI)?

The pH point at which the Protein has no overall charge

15

When pH of solution > pK of amino acid then?
And what happens vice versa?

Molecule will be deprotonation
Vice versa: molecule is protonated

16

Amino acids can be classified by what criteria?

Aromatic or aliphatic
Polar or non-polar
Charged or uncharged
Positive or negative (@pH7)

17

Acidic proteins contain?
Basic proteins contain?

Many negatively charged aa
Many positively charged aa

18

Acidic proteins have a ______ pI.
Basic proteins have a ______ pI.

Low
High

19

A peptide bond is formed between?

Two amino acids
Between a -COOH and a NH2 group

20

Describe a peptide bond

Planar
Condensation reaction to form
No rotation due to double bond 'characteristics'
Carbonyl oxygen and amide hydrogen in trans formation

21

What is the primary structure of a protein?
What bonds are involved?

Chain of amino acids
Covalent peptide bonds

22

What is the secondary structure of a protein?
What bonds are involved?

Stretches of alpha helix of beta sheet structures
Hydrogen bonds

23

Tertiary structure is?
Bonds involved are?

Full 3D structure of protein, involves folding up of secondary structures
Covalent (disulphide bridges)
Ionic
Van der waals
Hydrogen
Hydrophobic interactions

24

Quaternary structure is?

Interactions between multiple polypeptide chains within the same protein

25

Tertiary folding sometimes requires the help of?

Molecular chaperones

26

Quaternary proteins can be heteromeric or homomeric, explain the difference.

Homomeric proteins made up of all the same subunits
Heteromeric proteins have at least 2 different types of subunit eg. Haemoglobin.

27

Describe structure and functions of globular proteins

Several types of secondary structure Small and compact
Enzymes, regulatory proteins

28

Describe the structure and functions of fibrous proteins

One type of secondary structure
Long fibres
Structure support and protection

29

Major structural elements of alpha helices?

Right handed
3.6 aa per turn
0.54nm pitch

30

Describe the key feature of beta sheet structures.

Extended conformation
Parallel or anti parallel
Multiple inter strand h bonds

31

Name and explain why particular aa are strong helix formers or breakers.

Small hydrophobic aa such as ala or leu good formers
Pro acts as helix breaker due to rotation around the N-C bond being impossible
Gly acts as breaker because the tiny R group supports other conformations

32

Improper folding of protein's tertiary structure is characteristic of what class of diseases?

Amyloidoses