DNA crystals

7 posts / 0 new
Last post
Bettye
Bettye's picture
DNA crystals

Anyone have any experience working with DNA crystals under ambient conditions?

holeung
holeung's picture
How large is the DNA you are

How large is the DNA you are trying to crystallize? Give me more details on what you are trying to do, and I'll try to help.

Bettye
Bettye's picture
The DNA is ssDNA/10-mers that

The DNA is ssDNA/10-mers that form either B-DNA or a Holliday Junction.

I'm trying to image the crystals by atomic force microscopy (AFM) and obtain lattice resolution. The junction crystals have the flattest surface for imaging with AFM, but they crack and melt when trying to image.

I've tried various artifical mother liquors, some work, but usually the crystals eventually degrade. There is not enough original mother liquor for imaging.

holeung
holeung's picture
Have you been maintaining

Have you been maintaining vapor pressure/humidity of the crystal? Otherwise the crystal will dehydrate and degrade quickly.

Bettye
Bettye's picture
As best as I can. They seem

As best as I can. They seem to be relatively stable in the room in which they are grown. One of the biggest problems is that the the AFM is in another building, in the basement, where the temperature of the room is erratic.

I guess that makes it sound pretty impossible, doesn't it?

holeung
holeung's picture
I am not familiar with AFM

I am not familiar with AFM with DNA crystals. Can you layer the crystals with an oil to seal it from air?

Bettye
Bettye's picture
AFM works like a tiny record

AFM works like a tiny record player, a tip scans the surface. Oil might work, if it's not too viscous. I would worry about drag (friction) on the tip, because it's only about 10 nm wide.