Re: [ccp4bb] Missing DNA density in Protein DNA complex structure

2013-05-05 Thread Opher Gileadi
Hi Ashok, You say your DNA is palindromic - have you looked at the possibility that the longer DNAs are actually folded on themselves rather than duplexes of two separete oligos? Depending on the location of the centre of your palindrome and on interactions with adjacent molecules, this could

Re: [ccp4bb] Missing DNA density in Protein DNA complex structure

2013-05-05 Thread Phoebe A. Rice
oks/2008/9780854042722.asp From: CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] on behalf of Raji Edayathumangalam [r...@brandeis.edu] Sent: Sunday, May 05, 2013 7:39 AM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] Missing DNA density in Protein DNA complex structure Dear Ashok, There are many

Re: [ccp4bb] Missing DNA density in Protein DNA complex structure

2013-05-05 Thread Raji Edayathumangalam
Dear Ashok, There are many questions underlying your questions. A couple of things to check right off the bat: (1) Do you actually know that your crystal still contains all of the DNA bp that you started with? Did you analyze the contents of your crystal by native PAGE, mass spec or other methods

Re: [ccp4bb] Missing DNA density in Protein DNA complex structure

2013-05-05 Thread Paul Paukstelis
How is the DNA packed in the crystal? Coaxially stacked pseudo-infinite helices? --paul On 05/05/2013 02:21 AM, ASHOK KUMAR Patel wrote: Hi all, I am working on a DNA binding protein (mol wt around 30 kDa), which binds to Duplex DNA in a non-specific sequence manner. The structure has been

[ccp4bb] Missing DNA density in Protein DNA complex structure

2013-05-04 Thread ASHOK KUMAR Patel
Hi all, I am working on a DNA binding protein (mol wt around 30 kDa), which binds to Duplex DNA in a non-specific sequence manner. The structure has been published with 12 base pair duplex DNA. I am trying to understand the DBD protein DNA interaction even more by choosing different lengths a