[ccp4bb] AW: [ccp4bb] crystallization of complex and ...

2011-09-16 Thread alexander . pautsch
Dear Min, regarding #1 some things come to my mind: - What is the Kd that you got from the Biacore? And did you make sure that the sample is concentrated enough (both on gel filtration and in crystallization) to have a sufficient amount in the complex. - did you use the same buffer systems?

[ccp4bb] Silver staining Coomassie stained gels

2011-09-16 Thread K Singh
Dear All, Can anyone suggest me a protocol for silver-staining the PAGE that is already stained with Coomassie. Kris

Re: [ccp4bb] crystallization of complex and ...

2011-09-16 Thread Enrico Stura
Dear Min, Regarding the stoichiometry that you should use in crystallizing two proteins that form a complex. I have looked at this question before. See: Stura, E.A., Graille, M., Taussig, M.J., Sutton, B.J. Gore, M.G., Silverman, G.J., Charbonnier, J.-B. (2001) Crystallization of

Re: [ccp4bb] Why Does Cross-linking Mean Anything?

2011-09-16 Thread R. M. Garavito
Jacob, One of the problems with glutaraldehyde is the its chemistry is so bizarre. It actually forms quite long transient polymers in solution. You also have to ask yourself why formaldehyde also fixes tissues. This is why glutaraldehyde works so well for tissue fixation for EM as

Re: [ccp4bb] Mac OSX 10.7 Lion

2011-09-16 Thread Phil Evans
I use my MBP with external screen, keyboard mouse all the time. The new ones are fast, mine should easily cope with Lion My question about Lion was because 1. on the one hand as far as I can see Bill Scott only builds latest stand-alone Coots (0.7...) for Lion, and these don't work on 10.6

Re: [ccp4bb] Mac OSX 10.7 Lion

2011-09-16 Thread William G. Scott
Dear Phil (and everyone): 1. I've now got automated build systems for coot for 10.7.1 and 10.6.8. I just haven't had a chance to get the 10.6.8 one on line. I'll try to do this today. (Also, the last few haven't build due to a change in the code with which the compiler can't cope, but

Re: [ccp4bb] crystallization of complex and ...

2011-09-16 Thread Ed Pozharski
On Thu, 2011-09-15 at 22:20 -0400, m zhang wrote: Second is about reusing of Ni-NTA resin. According to Qiagen's instruction, after using fresh Ni-NTA resin, one only needs to wash the used Ni resin first with 0.5M NaOH, then with your own buffer. After that the resin is ready to be reused

Re: [ccp4bb] Silver staining Coomassie stained gels

2011-09-16 Thread Ed Pozharski
On Fri, 2011-09-16 at 15:28 +0530, K Singh wrote: Dear All, Can anyone suggest me a protocol for silver-staining the PAGE that is already stained with Coomassie. Kris Just destain it and then use the standard silver-staining protocol. If for some reason you want to have both stainings

[ccp4bb] about alternate conformations

2011-09-16 Thread Ming
Hi, I was using Refmac from CCP4 to refine a protein's crystal structure. The methionine has half selenium and half sulfur. I was trying to make alternate conformations and let refmac do the refinement. But it keeps giving me error message as follows: There is an error in the input coordinate

[ccp4bb] about alternate conformations

2011-09-16 Thread Ming
Hi all, I was using Refmac from CCP4 to refine a protein's crystal structure. The methionine has half selenium and half sulfur. I was trying to make alternate conformations and let refmac do the refinement. But it keeps giving me error message as follows: There is an error in the input

Re: [ccp4bb] Silver staining Coomassie stained gels

2011-09-16 Thread Artem Evdokimov
Destain it really well. One easy peasy option is to put the gel in water and add 1 or 2 ml of cheap Q sepharose to it then boil. Gel will destain in 2-3 minutes of boiling. On Sep 16, 2011 5:10 AM, K Singh ksc...@gmail.com wrote: Dear All, Can anyone suggest me a protocol for silver-staining the

Re: [ccp4bb] crystallization of complex and ...

2011-09-16 Thread Artem Evdokimov
1 imidazole affinity is not high which is why you use 200 mM or more to elute. So it comes off by itself. 2 you can wash with low ph and then recharge this is somewhat easier on the resin On Sep 15, 2011 9:25 PM, m zhang mzhang...@hotmail.com wrote: Dear all, I have two questions: First, I

Re: [ccp4bb] Silver staining Coomassie stained gels

2011-09-16 Thread Soisson, Stephen M
Now that's a nifty trick I hadn't heard of before! From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of Artem Evdokimov Sent: Friday, September 16, 2011 10:27 AM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] Silver staining Coomassie stained

Re: [ccp4bb] Silver staining Coomassie stained gels

2011-09-16 Thread Artem Evdokimov
It is nice indeed, that's how we stainand destain our gels in less than 8 minutes :-) there was at one time a proprietary product like tis called magic beads or somesuch. But regular resin works ;-) On Sep 16, 2011 9:31 AM, Soisson, Stephen M stephen_sois...@merck.com wrote: Now that's a nifty

Re: [ccp4bb] about alternate conformations

2011-09-16 Thread Ed Pozharski
On Fri, 2011-09-16 at 10:08 -0400, Ming wrote: The methionine has half selenium and half sulfur. Do you have the evidence that your incorporation ration was 50%? On a practical side, try giving the SeMET a different chain ID. You can change it back manually after refinement. Assuming that the

Re: [ccp4bb] about alternate conformations

2011-09-16 Thread Kevin Jin
I did not make it clear. The protocol we used for protein expression always limit the occ of MSE as 0.75. You may estimate your occ of MSE by ED. You can check PDB for JCSG structures. Cheers, Kevin On Fri, Sep 16, 2011 at 7:09 AM, Ming dongm...@udel.edu wrote: Hi all, I was using Refmac

[ccp4bb] DNA cif files

2011-09-16 Thread Gregory Bowman
I have a question about the bond angle restraints in the DNA cif files. I recently submitted a protein-DNA complex to the PDB, and found out that many of the glycosidic bond angles (atoms O4'-C1'-N9/N1) were outside the accepted range. I switched from CCP4 6.1.13 to 6.2.0 (installed/updated

Re: [ccp4bb] Silver staining Coomassie stained gels

2011-09-16 Thread Dima Klenchin
Can anyone suggest me a protocol for silver-staining the PAGE that is already stained with Coomassie. There is absolutely nothing wrong with silver staining of a Coomassie-stained gel without destaining. It only prevents blowout of most intense bands already well-visible with Coomassie. The

Re: [ccp4bb] DNA cif files

2011-09-16 Thread Ian Tickle
Hi, it depends what you mean by 'different'. The SUs of the new set are much lower than the old values (0.8 deg vs. 3.0) so one would assume that these are improved estimates based on new data. The difference between the old and the new is (108.4 - 107.8) = 0.6 deg with a SU of the difference of

[ccp4bb] Insoluble ligand?

2011-09-16 Thread Chaudhary, Ritcha
Hi All I have a ligand that is dissolved in 100% DMSO. The ligand crashes out even when diluted to 20% final DMSO concentration in the protein buffer. I have heard of people using detergents such as n octyl Beta D glucoside to keep the ligand solubilized at lower DMSO concentrations. Can

Re: [ccp4bb] Insoluble ligand?

2011-09-16 Thread Smita Mohanty
Hi Ritcha, Did you try Methanol or Ethanol to see if your ligand dissolve in these solvents? You should try these solvents first before adding any detergents. Good luck. Smita Mohanty Chaudhary, Ritcha chaudha...@missouri.edu 9/16/2011 11:04 AM Hi All I have a ligand that is dissolved in

Re: [ccp4bb] AW: [ccp4bb] crystallization of complex and ...

2011-09-16 Thread m zhang
To all and Alex, -The Kd is around 500nM from Biacore. -One of my protein tends to precipitate and is only stable below 3mg/m. If I concentrated it to higher concentration, it will precipitate a lot after 1hr. And it was previously crystallized at low concentration. But when I inject on gel

Re: [ccp4bb] Insoluble ligand?

2011-09-16 Thread Roger Rowlett
Keep in mind it may also be possible to soak in ligand from the solid if the binding constant is tight enough. Le Chatelier's principle will drag it from the undissolved solid into the complex. This process will be improved if you can increase solubility in

Re: [ccp4bb] UV imaging of crystals

2011-09-16 Thread Shiva Bhowmik
Would be curious to know the current limitations on UV microscopy employed for screening protein crystals - such as content of aromatic amino acids, protein size etc. Cheers, Shiva On Fri, Sep 16, 2011 at 1:19 AM, Klaus Fütterer k.futte...@bham.ac.ukwrote: From the experience when our

[ccp4bb] density modification help

2011-09-16 Thread James Garnett
Dear BB, I hope you can help. I have been trying to density modify my potential SAD solutions but I think it would help if I could conceptualize the arrangement of molecules in my crystals and it is making my head hurt. I have 2 crystal forms. I only obtained a single crystal for the first

[ccp4bb] Paper describing the structure of LFA-1

2011-09-16 Thread Narayanan Ramasubbu
Dear All: I would like to know the literature on the crystal structure of Leukocyte Function-Associated Antigen One (LFA-1, CD11a/CD18). I have the structure of I domain but not for the entire molecule. I would greatly appreciate if people can point me to the right article/reference. Thanks

Re: [ccp4bb] stereo

2011-09-16 Thread Sabuj Pattanayek
Hi, On Thu, Sep 15, 2011 at 1:55 PM, Hena Dutta hdutt...@gmail.com wrote: Hi Sabuj, Thanks for all your answers. I finally came to this plan. Please tell me if I am doing anything wrong. Option 1. HP Workstation Z400 FL998U8#ABA Desktop PC - Intel Xeon W3550 3.06GHz, 8GB DDR3, 160GB 10k

Re: [ccp4bb] Paper describing the structure of LFA-1

2011-09-16 Thread Ed Pozharski
On Fri, 2011-09-16 at 14:10 -0400, Narayanan Ramasubbu wrote: Dear All: I would like to know the literature on the crystal structure of Leukocyte Function-Associated Antigen One (LFA-1, CD11a/CD18). I have the structure of I domain but not for the entire molecule. I would greatly appreciate

Re: [ccp4bb] Protein preps become a jelly

2011-09-16 Thread Phoebe Rice
Gamma delta resolvase catalytic domain stock solutions used to make a nice clear jelly at 4 degrees, but it was perfectly reversible by warming the sample to room T. In fact, one mutant crystallized in the stock tube after a few trips in and out of the fridge. The crystals didn't diffract

Re: [ccp4bb] Protein preps become a jelly

2011-09-16 Thread Jacob Keller
I think I know another protein that does this: gelatin! (Well, not the crystallization part...) Jacob On Fri, Sep 16, 2011 at 2:41 PM, Phoebe Rice pr...@uchicago.edu wrote: Gamma delta resolvase catalytic domain stock solutions used to make a nice clear jelly at 4 degrees, but it was