Supersecondary Structures and Structures

Question 1

Alpha Keratin

Answer 1

• 2 alpha helices
• each individual helix is right handed
• the 2 alpha helices are wound around each other in a left-handed manner

Question 1

Collagen

Answer 1

• 3 helices (not alpha helices) would around each other in a right handed twist
• repeat of Gly- X- Y
• Gly at every 3rd position makes it possible to bring the chains very close together

Question 2

Beta hairpin

Answer 2

-present in most antiparallel beta structures
-typically consists of 4 antiparallel beta strands

Question 3

Greek key motif

Answer 3

4 adjacent antiparallel beta strands

Question 4

beta-alpha-beta

Answer 4

2 parallel beta strands