protein structure Flashcards
secondary structure: distinguish between an α-helix and a β-pleated sheet and appreciate the bonds that stabilise their formation
1
Q
how is the a-helix stabilised
A
hydrogen bonds between NH and CO of different residues
2
Q
how many amino acids along the helix
A
4
3
Q
what a-helix is more stable
A
right-handed
4
Q
which direction do the side chains project
A
out
5
Q
why does proline form a kink
A
NH lost, so can’t hydrogen bond with CO, forming kink
6
Q
how is the B-pleated sheet stabilised
A
hydrogen bonds between NH and CO (at right angles to backbone) of 2 or more B-strands
7
Q
why might it be parallel or antiparallel
A
depends on best hydrogen bond alignement
