Re: [ccp4bb]: di-citrate complex

[Jean-Paul Renaud <renaud@titus.u-strasbg.fr>]

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>Hi all,
>
>I have a structure that has two citrate molecules strongly associated to
>each other through their C6 carboxylate groups.
>Has anyone had this type of inter-carboxylate interaction?
>How do I describe this tight association so that X-plor will not have them
>repel each other? Will it be sufficient to explicitely protonate the
>acidic groups?
>
>Thanks
>
>
>Deena Oren, PhD                                  732-235-4498
>Center for Advanced Biotechnology and Medicine
>Rutgers University
>679 Hoes ln                                 fax: 732-235-5669
>Piscataway, NJ 08854                    oren@cabm.rutgers.edu


Wouldn't it be a classical hydrogen bond pairing of the carboxylic (not 
carboxylate) groups?

    O - - - - HO
C                   C
    OH - - - - O

Is this compatible with the geometry you observe?
Cheers,


Jean-Paul






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Dr Jean-Paul RENAUD
Laboratoire de Biologie et Genomique Structurales
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