Re: [ccp4bb] ligand bonds (AlF3) breaking up after refinement in refmac

2015-01-17 Thread Matthew BOWLER
Dear Ansuman, I agree with Matthew that the refinement seems to be OK - the reason the bonds are longer is because what you actually have bound is MgF3- and not AlF3. MgF3- is a much better transition state analogue as it is isosteric and isoelectronic with a transferring phosphoryl group. At p

Re: [ccp4bb] additional density on cysteine residue

2015-01-17 Thread Savvas Savvides
Dear Sreetama, I would consider the possibility that this active site cysteine is involved in a mixed-disulfide with beta-mercaptoethanol, which is present at a considerable concentration in your protein buffer. The fact that the residual density in both the Fo-Fc and 2Fo-Fc maps actually incr

Re: [ccp4bb] additional density on cysteine residue

2015-01-17 Thread Robbie Joosten
Hi Sreetama, The water S-gamma distance made me think that it might be a cysteine beta-mercaptoethanol adduct. Try building CME instead of CSO. Cheers, Robbie -Oorspronkelijk bericht- Van: "sreetama das" Verzonden: ‎17-‎1-‎2015 19:27 Aan: "CCP4BB@JISCMAIL.AC.UK" Onderwerp: [ccp4bb] ad

[ccp4bb] Redundancy vs no of frames

2015-01-17 Thread rohit kumar
Dear all, Can anyone tell me how to calculate number of frames from redundancy or vica versa Thank you

Re: [ccp4bb] additional density on cysteine residue

2015-01-17 Thread Keller, Jacob
Maybe somehow do partial cys partial cme, refine occupancies—is this possible in refmac? JPK From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of sreetama das Sent: Saturday, January 17, 2015 3:11 PM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] additional density on cysteine

Re: [ccp4bb] additional density on cysteine residue

2015-01-17 Thread Robert Stroud
I suspect it may be a reaction with your reducing agent. What did you use either in the preparation, or in the crystallization. If you didn’t have reducing agent it probably oxidized to sulfuric acid. You should figure it out with difference maps and maybe mass spec also. bob > On Jan 17, 2015,

Re: [ccp4bb] X-ray Source Differences (WAS: RE: [ccp4bb] How far does rad dam travel?)

2015-01-17 Thread James Holton
If there are no other noise sources, then then final signal to noise of measuring the photons you describe is always EXACTLY the same. This is why photon-counting is such a useful "error currency": doesn't matter how you slice them up or lump them together. Photons are photons, and the square

[ccp4bb] Visualizing Stereo view

2015-01-17 Thread jeorgemarley thomas
Dear all, First of all sorry to put this off topic and silly question on bb. Can anybody suggest me, how to create a stereo image and how it is different from the normal. How can I visualize it, if anybody has answer for this please suggest me its significance in analysis. Thank you very much in a