1003: Revisiting Puzzle 141: Rosetta Decoy 5

Closed since over 11 years ago

Summary

• Created: October 21, 2014
• Expires: October 30, 2014 at 23:00 UTC
• Max points: 100

Description

This is a throwback puzzle to the early days of Foldit. This protein helps to regulate oxidation in the cell; the starting structure is a model produced by Rosetta. We are revisiting old Foldit puzzles so we can see how useful the recent additions to the game have been.

Top groups

• 11. Italiani Al Lavoro 13 pts. 9,615
• 12. Deleted group pts. 9,557
• 13. Russian team 7 pts. 9,549
• 14. Deleted group pts. 9,364
• 15. xkcd 4 pts. 9,346
• 16. It's over 9000! 3 pts. 9,315
• 17. Natural Abilities 2 pts. 9,085
• 18. Deleted group pts. 9,075
• 19. Waverki 1 pt. 8,750
• 20. Eὕρηκα! Heureka! 1 pt. 8,711

Top soloists

• 1. LociOiling 100 pts. 9,904
• 2. BitSpawn 98 pts. 9,881
• 3. retiredmichael 97 pts. 9,861
• 4. Bruno Kestemont 95 pts. 9,788
• 5. gitwut 93 pts. 9,771
• 6. Galaxie 91 pts. 9,760
• 7. frood66 89 pts. 9,739
• 8. karstenw 87 pts. 9,733
• 9. mirp 85 pts. 9,726
• 10. KarenCH 84 pts. 9,714

Comments

[brow42]

Is it common for bridges to from between cysteines that are this close?

[bkoep]

Not necessarily. In general, cysteines that are far apart in sequence can contribute more to the stability of a protein fold.

Since these two cysteines are so close in sequence, we can assume that this disulfide bond contributes very little to the stability of the protein. This makes sense, if we consider that this protein is involved in regulating the reduction potential of the cell: In order for the protein to function, the disulfide should be readily oxidized (formed) or reduced (broken) in response to changing conditions in the cell. This particular protein must remain folded even when the disulfide bond is reduced, so that the two cysteines are properly positioned and ready to bond.

[brow42]

I see! So, this is a redox potential buffer, analogous to a pH buffer! Thank you for the response!