Re: [ccp4bb] immobilized DNA resin

2011-04-10 Thread Garnett, James A
Hi Alex, as you have a DNA binding protein does it have a high pI? If so, good old ion exchange with an S-sepharose column should do it. Cheers James Dr James Garnett Division of Molecular Biosciences, Imperial College London, Level 5, Biochemistry Building, South Kensington, LONDON SW7 2AZ,

Re: [ccp4bb] immobilized DNA resin

2011-04-10 Thread Jacob Keller
Related fact I learned recently, perhaps of interest for fellow record-keepers: heparin sulfate has the highest negative charge density of any known biological molecule. JPK On Sat, Apr 9, 2011 at 9:38 PM, Raji Edayathumangalam r...@brandeis.edu wrote: Hi Alex, Most DNA-binding proteins has

Re: [ccp4bb] immobilized DNA resin

2011-04-10 Thread Dima Klenchin
heparin sulfate has the highest negative charge density of any known biological molecule. Seems to me that phytic acid (IP6, C6H6-(H2P04)6) and inositol heptakisphosphate (IP7) should have higher charge per mass and per volume. - Dima

Re: [ccp4bb] immobilized DNA resin

2011-04-10 Thread Jacob Keller
Hey, does Wikipedia lie? Also, the reference is to Lehninger's text, although I did not verify it. http://en.wikipedia.org/wiki/Heparin On Sun, Apr 10, 2011 at 3:37 PM, Dima Klenchin klenc...@facstaff.wisc.edu wrote: heparin sulfate has the highest negative charge density of any known

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-10 Thread E rajakumar
Hi Arpita You can try QUANTI-iT Protein assay kit from Invitrogen. But still there is nearly 20-50% discrepancy between this method and a Abosorbance at 280. I also faced same problem with a protein, then re-cloned by adding a Trp at the C-terminus. Raj   E. Rajakumara Postdoctoral Fellow

[ccp4bb] Used AREIMOL to judge the steric clashes

2011-04-10 Thread Hailiang Zhang
Hi, I have 2 rigid and fixed proteins and want to quickly judge whether there are some steric clashes. One quick way I am thinking is using CCP4 AREAIMOL to calculate the surfaces of each individual protein as well as the heterodimer, and check whether the sum of the two individual surfaces is

Re: [ccp4bb] Used AREIMOL to judge the steric clashes

2011-04-10 Thread Edward A. Berry
Areaimol is good for determining the contact area from the difference you mentioned. If you want to distinguish real clashes from comfortable van-der-Waals contacts, you can use pdbdist3: http://sb20.lbl.gov/berry/for/pdbdist3.for The two molecules have to be in separate pdb files. You

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-10 Thread gauri misra
Hi, You can read the spectrophotometric absorption at 280 nm and 200nm in UV range. It should serve your purpose and provide a decent idea for the amount of protein in the sample. Provided that absorbance at 280nm is given by aromatic rings but at the same time absorbance at 200nm is contributed

[ccp4bb] O-linked glycosylation refinement in Phenix

2011-04-10 Thread Qiang Chen
Dear all, I'm refining a structure which has both N-linked and O-linked glycosylation. I use Phenix to do the refinement. It works well for the N-linked NAG. I defined the link as the following: apply_cif_link { data_link = NAG-ASN residue_selection_1 = chain A and resname NAG

Re: [ccp4bb] Used AREIMOL to judge the steric clashes

2011-04-10 Thread Hailiang Zhang
Thanks Edward! Actually Areaimol works well for my problem. But now I have a new issue looking for some advice. I want to randomly generate some points in the unit cell and make a quick judgment whether it is outside of the solvent mask or not. It seems that Areaimol doesn't help at this point,