Hi there
AMPLE works very well for coiled-coil structures, irrespective of
parallel/anti-parallel etc
http://journals.iucr.org/m/issues/2015/02/00/lz5005/
Resolution permitting, SHELXE tracing and phase modification, built into
the AMPLE pipeline, gives statistics that differentiate very clearly
between success and failure.
I also understand that ARCIMBOLDO works very well for coiled-coils
Good luck
Daniel
On 21/07/17 08:37, herman.schreu...@sanofi.com wrote:
Hi ???,
Coiled coil structures can be very tricky with MR, so your solution
may not be correct. You could try to split your search model and run
MR with the separate coils. If you have high enough resolution (> ~2.3
Å?) and your MR solution is basically correct, you may be able to
solve your problem by rebuilding and refinement, but this may be a lot
of work. Without any details (resolution of the data, current
Rwork/Rfree etc.) it is difficult to give any more specific advice.
Best,
Herman
*Von:*CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] *Im Auftrag
von *???
*Gesendet:* Freitag, 21. Juli 2017 03:17
*An:* CCP4BB@JISCMAIL.AC.UK
*Betreff:* [ccp4bb] high Rfree
Hi everyone
I have got a anti-parallel coiled-coil structure in a short
fragment recently, then I want to solve a longer fragment structure
with phenix-MR using this short fragment structure as a model.The
result is not good because of the Rwork and Rfree is high.So
<https://urldefense.proofpoint.com/v2/url?u=http-3A__high.So&d=DQQGaQ&c=Dbf9zoswcQ-CRvvI7VX5j3HvibIuT3ZiarcKl5qtMPo&r=HK-CY_tL8CLLA93vdywyu3qI70R4H8oHzZyRHMQu1AQ&m=66oGBkFu_vOT7n3Fp-7licSV3JzUrtBbobSB9EEKws0&s=wYjH3MkMtX51bkladsLunNIv3g08mTlwh2zW9rna7rA&e=>
I think the longer fragment will be parallel coiled-coil which is
different with the shorter one. I am wondering whether there are any
other methods to handle this phenomenon besides heavy atom phasing?
Thanks a lot!!!
--
Dr Daniel John Rigden Tel:(+44) 151 795 4467
Institute of Integrative Biology FAX:(+44) 151 795 4406
Room 101, Biosciences Building
University of Liverpool http://pcwww.liverpool.ac.uk/~drigden/
Crown St.,
Liverpool L69 7ZB, U.K.
