Following statements are made related to protein structure
A. The hydrogen bonding patterns between the CO and NH groups are: n → n +3 in α -helix; n → n + 4 in 310 helix and n → n + 5 in π helix.
B. In a β turn, there are 10 atoms between the hydrogen bond donor and acceptor.
C. In a γ turn, there are 6 atoms between the hydrogen bond donor and acceptor.
D. Parallel sheets have evenly spaced hydrogen bonds, which bridge the strands at an angle.
Which one of the following combinations of above statements is correct?
1
A and C
2
A and B
3
C and D
4
B and D