Re: [ccp4bb] pKa for protein C-terminus?

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

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Subject: pKa for protein C-terminus?
From: Patrick Loll pat {- dot -} loll {- at -} DREXEL {- dot -} EDU
Date: 2008-09-05

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Subject: Re: pKa for protein C-terminus?
From: Roger Rowlett rrowlett {- at -} MAIL {- dot -} COLGATE {- dot -} EDU
Date: 2008-09-06

You are correct. See */Protein Sci/* Thurlkill et al. 15 (5): 1214,
http://www.proteinscience.org/cgi/reprint/15/5/1214, which is a recent
effort to codify "typical" pKa values for protein ionizable groups.

Cheers,

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Roger S. Rowlett
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Patrick Loll wrote:
> What value do we expect for the pKa of a protein's C-terminal
> carboxylate? pKa values for free amino acids are quite low (2-3), but
> it seems to me that this may have something to do with the proximity
> of a free amine group; I'd expect a higher value (4-ish?) for the
> peptide's C-terminus.
>
> A quick & lazy search using the term "pka" was stymied by a gazillion
> references to protein kinase A...
>
> Thanks,
> Pat
>
>
> ---------------------------------------------------------------------------------------
>
> Patrick J. Loll, Ph. D.
>
> Professor of Biochemistry & Molecular Biology
>
> Director, Biochemistry Graduate Program
>
> Drexel University College of Medicine
>
> Room 10-102 New College Building
>
> 245 N. 15th St., Mailstop 497
>
> Philadelphia, PA 19102-1192 USA
>
>
> (215) 762-7706
>
> pat.loll@drexelmed.edu
>
>

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: pKa for protein C-terminus?
From: Patrick Loll pat {- dot -} loll {- at -} DREXEL {- dot -} EDU
Date: 2008-09-05

Next message:
Subject: CNS refinement problem
From: jxqi jxqi {- at -} MAIL {- dot -} IM {- dot -} AC {- dot -} CN
Date: 2008-09-06