[ccp4bb] Pittsburgh Diffraction Conference 2012

The 70th Pittsburgh Diffraction Conference will be held at SSRL between September 30th and October 2nd 2012 and will feature 2 full days of lectures and poster presentations. The conference starts with a welcome reception on September 30 and there will be a banquet on the evening of October 1st.

Re: [ccp4bb] off topic: reduced glutathione interfering with protein activity?

Peter, Yes, in our hands it can eluted completely. Usually 20 ml of elution buffer per 2 ml of GS4B resin (GE healthcare, fast flow) is enough . We use 30 ml open-columns for purification - each column has 2 ml of resin. Vitali On Wed, Aug 29, 2012 at 3:02 PM, wrote: > Hi Vitali, > > I usually

Re: [ccp4bb] Plastic and glass plates

Theresa, The major advantage of the plastic plates is indeed ease of harvest. However, the plastic plates also tend to have some evaporation issues and eventually dry out after a few months, where as the glass plates basically last forever. On the other hand, protein crystals in LCP tend to form

Re: [ccp4bb] off topic: reduced glutathione interfering with protein activity?

Peter, Such high concentration of GSH may change the pH according to our experience. We usually use 50 mM Tris pH=8.0, 5 mM GSH, 3 mM DTT - so that you can load the sample on ion-exchange column after elution. If your protein is not stable without NaCl - you should add it also. Vitali On Wed, Au

[ccp4bb] Plastic and glass plates

Dear all Is there any pros and cons of using plastic plates for LCP crystallization? The glass is clearer but it is very difficult to open. Thank you.

Re: [ccp4bb] Negative electron Density for Zinc

Thank You very much everyone. I took all your suggestions into consideration. I was able to solve the problem Thank You once again Deepthi On Tue, Aug 28, 2012 at 5:07 PM, Pavel Afonine wrote: > Hi Deepthi, > > 1) refine anisotropic ADPs for Zn, > 2) make sure charge is accounted for, > 3) r

Re: [ccp4bb] Jelly body refinement?

Hi Gunnar, A couple of comments, to clarify a few of the similarities and dissimilarities between DEN and analogous technologies: According to your very nice paper from 2010, DEN refinement with gamma=0 gives a higher weight to external information, whilst gamma=1 ignores external information

Re: [ccp4bb] off topic: reduced glutathione interfering with protein activity?

I don't think so since I purify in the presence of reducing agents (DTT/BME) and I got activity out of the prep that was released by on column cleavage. On the other hand, I don't usually add those fresh each time I use the buffers so it's entirely possible the reducing agents are nowhere near

Re: [ccp4bb] off topic: reduced glutathione interfering with protein activity?

GSH will reduce your protein quite nicely - is your enzyme activity redox sensitive? --- Dr Antony W Oliver Senior Research Fellow CR-UK DNA Repair Enzymes Group Genome Damage and Stability Centre Science Park Road University of Sussex Falmer, Brighton, BN1 9RQ email: antony.oli...@sussex.ac.u

[ccp4bb] off topic: reduced glutathione interfering with protein activity?

Hi all, I've been purifying my protein off a GST column and have noticed a massive difference in activity of my protein between a prep that was freed from the column via on column cleavage, and a prep that was eluted (20mM GSH) and then cleaved and further purified. I'm suspecting that the glut

Re: [ccp4bb] Negative electron Density for Zinc

I wish I could give a sensible explanation, but this feature is very common with heavy atoms. Possible problems. The default wavelength for all atomic scattering functions is Cu Ka - you can see the formula used and details in the file $CLIBD/atomsf.lib. The atomic scattering values are much t