Fitting inside analysis would of course be wonderful, but as Rasmus says
it's a bit of work. In principle Frank Delaglio's nlinls program can be
used to do it. A start point would be:
https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=CCPNMR;C4G9HQ;20080204102530%2B0000
but will need to be modified for J coupling fitting for sure.
Brian
On Thu, 29 Oct 2009, Rasmus Fogh wrote:
> Dear Mateusz,
>
> As far as I know we are just putting in splitting measurements at this time.
> Precise coupling constant mesurements require special techniques that correct
> for partial cancellation of positive and negative peaks. There has been a few
> in teh litterature, from memory. That would be a good thing to have, and we
> may well add it some day, but we are not close to putting it in at the
> moment.
>
> Yours,
>
> Rasmus
>
> ---------------------------------------------------------------------------
> Dr. Rasmus H. Fogh Email: [log in to unmask]
> Dept. of Biochemistry, University of Cambridge,
> 80 Tennis Court Road, Cambridge CB2 1GA, UK. FAX (01223)766002
>
> On Thu, 29 Oct 2009, Wayne Boucher wrote:
>
>> The 3J HN-HA that is currently in Analysis is the intensity-based 3D
>> measurement where you compare the HN-HA peak with HN-HN diagonal.
>>
>> The splitting functionality will be added in the next couple of months (at
>> least that is the current plan). Now how clever any of this will be for
>> overlapped peaks is a hard question.
>>
>> Note that in 2.1.1 Analysis there is an option of setting the x, y location
>> to be displayed in Hz, and to measure the difference between two
>> user-specified points on the screen. I imagine that would help you right
>> now.
>>
>> Wayne
>>
>> On Thu, 29 Oct 2009, Mateusz Maciejewski wrote:
>>
>>> Hello,
>>>
>>> I am currently working on a structure of a peptide, and have only natural
>>> abundance samples of it. The approach I assumed to measure the HN-HA 3J
>>> couplings was from a DQF-COSY, however, I couldn't find a way in
>>> analysis2.0
>>> to make precise measurements that would account for partial overlap of
>>> in-phase and anti-phase peaks. Is there any way to actually make such
>>> measurements in analysis2.0?
>>>
>>> Regards,
>>> Mateusz Maciejewski
>>>
>>
>
Dr. Brian O. Smith ---------------------- B Smith at bio gla ac uk
Division of Molecular & Cellular Biology,
Faculty of Biomedical & Life Sciences,
Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, UK.
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