1. It’s alive!: The phenomenon of viral breathing
Structural Journal Club
August 25, 2011

2. What is viral breathing?
Breathing is when the capsid undergoes reversible conformational changes not induced by an outside source. Example: An eternal epitope is exposed on the capsid surface periodically without the presence of receptor.

4. Digestion Time Course

5. Crystal Structure of VP4

6. Digestion in the presence of Drug

8. Digestion with Antibody

9. Stability of Digestion
Mutant: V1188M/
C1199W

11. Internal neutralization sites
VP4
VP1 N terminus

12. Temperature Dependence

13. Reversibility of Internal Neutralization

15. Neutralization by vp4 antibody

16. Cross reactivity of antibodies

18. CVB3 Strain CPE Three strains of CVB3:
28 – cause complete CPE on HeLa but not RD, representative strain
RD – DAF binding strain
RDVa – variant of RD which emerged from carrier culture

19. Hemagglutination (daf binding)

20. Ligand Binding of CVB3 HeLa RD RD Carrier DAF CAR CVB3/28 CVB3/RD
CVB3/RDVa

21. Growth Curves
HeLa RD
RD Carrier
CVB3/28
CVB3/RD
CVB3/RDVa

22. CVB3 Decay
CVB3/28
CVB3/RDVa
CVB3/RD

23. Amino Acid Changes in CVb3

24. What we have done
Incubated CVB3-RD with CAR at 4 °C, RT, and 37 °C and saw the following: 4° RT
37°
37°

26. What we want to do
Repeat Carson’s decay experiment to determine what the virus is doing to loose infectivity
Negstain of different time points
Gel of time points
Western of time points
Eventually would like to put it on affinity grid
Virus on lipid alone without receptor to determine whether it will undergo conformation change on lipid alone
Receptor doesn’t bind all over the virus – only one position

27. Now for something completely different!
Warning: you should not try the following at home! You will never be able to publish this!

29. 135S and 135s-p1

30. 80s-p1 complexes

31. P1 fab on PV

32. 1 or 8 Particle reconstruction