[ccp4bb] Differentiating bound Mn Ca.

Dear all. I have recently solved a structure in-house, 2.8A, CuKa. I have a metal ion bound very obvious hepta-valent co-ordination, which would suggest either Ca or Mn. Neither was present in the crystallisation setup, but there was some Mg around, which has contaminants of both Ca Mn. At

Re: [ccp4bb] Differentiating bound Mn Ca.

Hey David, You can do Mn2+ identification by its anomalous diffraction using the Cu Kalpha radiation. Mn is an anomalous scatterer at Cu Kalpha (1.5418 A), despite being distant from its absorption edge (somewhere around 1.96 A if I remember well). I did this for a double-manganese bound

[ccp4bb] imosflm bug for Mar 225 (3x3) detectors

There is a bug in the latest imosflm (v0.5.2) which prevents the correct direct beam coordinates being read from the image header for Mar 3x3 tiled CCDs (225mm square, as installed on ID23-1 and BM14 at ESRF for example). This is the ONLY detector affected by this bug. When the program cannot

Re: [ccp4bb] Differentiating bound Mn Ca.

Hi David, You can use Sheldrick's Calcium Bond Valence Sum to descriminate between metals (see Muller, P., Kopke, S., and Sheldrick, G. M. (2003) Acta Crystallogr., Sect. D: Biol. Crystallogr. 59, 32-37) even at low resolution. I have had good success with this method combined with estimation

[ccp4bb] Team Leader in Structure-Based Drug Design

Team Leader in Structure-Based Drug Design Institute of Cancer Research, London The Institute of Cancer Research is seeking to appoint a Team Leader, who will spearhead the establishment and development of high-throughput approaches to structure-based drug design within The Institute of Cancer

Re: [ccp4bb] Differentiating bound Mn Ca.

In cases like this I use the S atoms to calibrate the peak height. Of course it isnt definitive a) it is near the noise level, and b) peak height is very dependent on B factor.. But the ratio might distinguish between an atom with an f of 1.3 or f=2.8 Eleanor David Briggs wrote: Dear all. I

Re: [ccp4bb] Differentiating bound Mn Ca.

Although the peak height of S atoms can be used as an internal yardstick, one has to worry about differences in occupancy and possibly hetergeneous sites (i.e. Ca, Mn and Mg) which can confuse the interpretation of the results. On Mon, 16 Apr 2007, Eleanor Dodson wrote: In cases like this I

Re: [ccp4bb] Selenomethionine reduction v.s. disulfide bond

Hello Tiancen, The pundits often suggest keeping the selenium reduced (and indeed, it's not a bad idea) however if you're worried about disulphides - I would say that they take precedence over the selenium. If you work reasonably fast you should be able to have the best of both worlds - have the

Re: [ccp4bb] salt or protein?

Multiple overlapping salt lattices can sometimes look like protein diffraction, as long as you're looking in only two dimensions. However, if you can find the dominant rings, you should be able to discriminate since the c-spacing of salt would nearly always be pretty small. Consider powder

[ccp4bb] imgCIF workshop (new series) at BSR 2007

Third imgCIF workshop (new series) at BSR 2007 in Manchester and at Diamond: The Management of Synchrotron Image Data: Changes to the imgCIF dictionary and software, interaction with NeXus Sponsored by DOE under grant ER64212-1027708-0011962, NSF under grant DBI-0610407. You are cordially

[ccp4bb] Openings for Phaser team

There are two positions available for people to join the team developing Phaser, funded by the NIH grant that supports the development of the Phenix package. (Of course, the same version of Phaser goes into CCP4 as well!) If you're interested, please look at

Re: [ccp4bb] salt or protein?

Hi Sreeram, assuming you have plenty of those crystals, why don't you loop a few pass them through a drop of your reservoir for washing and load them on a SDS gel ? Juergen Sreeram Mahesh wrote: Hi All! I have been trying to screen for my protein crystals, from the crystals grown

[ccp4bb] FOM label in SigmaA

We need to run phase combination twice with SigmaA via CCP4i and encountered some confusion in FOM column label assignment. First, two sets of MAD phases are combined, we have output figure of merit, WCMB, from the input FOM_mad1 and FOM_mad2. Second time, we wanted to combine the Fc and PHIC

[ccp4bb] Crystallization Course: focus on membrane proteins 2007

Crystallization: focus on membrane proteins. http://www.nsls.bnl.gov/newsroom/events/workshops/2007/crys/ The Crystallization Course at Brookhaven National Laboratory this year will focus on membrane proteins. Sponsored by the IUCr the purpose of the course is to provide participants with

[ccp4bb] phosphorylation of protein is troublesome or not for crystallization

Dear all, Below is a question my friend asked me, but I have never worked on phosphorylated proteins. Has anyone worked on crystallizing phosphorylated proteins and can you comment on it? Thanks Rongjin Guan -- I would