April 11

Question 1

Spike protein needs to be _____ to allow fusion. This lets remainder of spike remain ____ state for a short time, before it closes again as open state is unstable

Answer 1

Cleaved by hosts proteins, open state

Question 2

Why does imposing symmetry improve resolution? How applied to Covid-2

Answer 2

It is that glycosylation in this case will then assign particle orientation for the trimeric spike protein. We can then essentially triple our data set, each image is duplicated so 3 copies total. This is because we can apply each image for each fold axis of orienation. This will increase resolution

Question 3

Why can’t see glycosylation for Cryo-ET?

Answer 3

It is because different ones at same sites, also they are flexible

Question 4

What diff in spike mainly do we see from Cov-1 to Covid-2?

Answer 4

Spike protein is more flexible, could increase infection

Question 5

How does COVID virus remain hidden from immune system>?

Answer 5

Host proteins will add endogenous sugars to glycosylation sites = glycan shield