Re: [ccp4bb] small-angle scattering and radiation damage control

[Joerg Stetefeld]

we have excellent experiences with cocoamidopropylbetaine (CAPB)
especially in SAXS experiments of protein-protein and protein-rna complexes,
js

At Thu, 9 Jul 2009 17:57:36 -0700, Susan Tsutakawa wrote:


Hi Bill,

5-10% glycerol usually helps in the majority of cases.  However, some
proteins require a scan of different conditions and different protein
concentrations.  Like everything else, it's protein dependent.
Changing the wavelength can also make a difference.  I also know some
SAXS beamlines like at the APS have capillary flow cells so they just
do hit and runs.

Susan


On Jul 9, 2009, at 4:45 PM, William Scott wrote:


Hi folks:

A colleague of mine here is doing small angle X-ray scattering at   
SSRL and finding his samples are suffering significant radiation   
damage.  He asked me for advice as to what potential radical   
scavengers might be useful. I told him to take 10 mg of ascorbic   
acid and to call me in the morning.


Anyone have a better suggestion that I might be able to pass along to him?

Many thanks in advance.

Bill

[ccp4bb] S-Met replacement

[Joerg Stetefeld]

  Dear All

  what are the experiences in the community in terms of  
physico-chemical property changes if one replace a S-Methionine by a  
Se-Methionine?


  Are there structural  a/o functional changes known, e.g. the wild type 
protein binds a ligand whereas the Se-Met version does not?

thank you in advance

Jörg Stetefeld, Ph.D.