[ccp4bb] Measuring protein concentration with 2mM ATP around

Dear all, We're doing some crystallization trials on a protein that requires 2mM ATP in the buffer and we are having trouble measuring reliably/reproducibly protein concentration. This is a real problem for optimization (last screen failed because of excessive protein concentration compared

Re: [ccp4bb] Measuring protein concentration with 2mM ATP around

Dear Cedric, Try the BCA protein assay. We get reliable results with this, consistent with amino acid analysis. I should say that this is using the 2ml format. We do not get reliable results with the microplate method. We use 5 μl samples and our regular buffer is not too different from

Re: [ccp4bb] Measuring protein concentration with 2mM ATP around

Try preparing your Bradford standard curve with your protein buffer (including the ATP). This is how I reliably get around detergent and other compounds that interfere. Hope this helps, Kelly *** Kelly Daughtry, Ph.D. IRTA Fellow Mechanisms of

[ccp4bb] CCP4-6.4.0 Update 007

Dear CCP4 Users, An update for the CCP4-6.4.0 series has just been released, consisting of the following changes: * pointless * fixed crash when using reference data with no alternative indexing * with multiple files, include columns present in any file * added crash

Re: [ccp4bb] Measuring protein concentration with 2mM ATP around

The solution might be as simple as measuring absorbance at 290 nm. We routinely measure concentrations in the presence of 100 uM ATP ( usually without concentrating though). That said 2 mM ATP is a lot more than we usually deal with and may interfere even at 290 nm. The interference from ATP

[ccp4bb] postdoctoral cryomicroscopy positions in London

Two 3-Year Postdoctoral Scientist Positions National Institute for Medical Research (NIMR), London NIMR will become part of the Francis Crick Institute (www.crick.ac.uk) Informal enquires may be made by email: Peter Rosenthal pros...@nimr.mrc.ac.uk https://cryoem.nimr.mrc.ac.uk/ (1)

[ccp4bb] TTP Mosquito Deck Configuration File

Does anyone have a TTP Mosquito robot Deck Configuration file for XQ-P-96S-C plates (3 wells x 96) made by MiTeGen? -- David M. Mueller Biochemistry and Molecular Biology The Chicago Medical School Rosalind Franklin University of Medicine and Science Green Bay Road North Chicago, IL 60064

Re: [ccp4bb] seeding, reproducibility

Dear Mahesh, cross-seeding into other conditions often works but still the chances are much lower than seeding the same form. Best wishes, Matthias (Please desist from sending so large attachments to half the planet!) - Dr. Matthias Zebisch Division

Re: [ccp4bb] seeding, reproducibility

Mahesh, this is a very interesting and slightly controversial question. One approach is to mix together all of the crystals that you have in the initial screen. The idea at the beginning of the project is to get as many diverse hits as possible - you can worry about crystal size, space group and

Re: [ccp4bb] seeding, reproducibility

Thanks you for the suggestions, Patrick and Matthias. I was actually wondering if any of the components from the seeding solution actually were important but your explanations sound more logical. I apologize for the large attachment. I did not realize that it was so big. Have a nice weekend !