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Re: mmCIF extension dictionary released for review ...

John Westbrook (jwest@ndb.rutgers.edu)
Wed, 15 Apr 1998 19:43:20 +0000 

Eleanor Dodson wrote:

>  We are looking at various definitions for the chem_comp records.
>
> Is there meant to be an entry for each linking peptide, and for each
>  terminal residue?
>
> loop_
> _chem_comp.id
> _chem_comp.type
> ALA
> ALAN L-peptide NH3 amino terminus
> ALAC L-peptide COOH carboxy terminus
> ARG  L-peptide linking
> ARGN .....
>
>  Eleanor Dodson
>

Hi Eleanor,

The component types are designed to specify, in a generic fashion, the
manner in which the component may link (or not link if the component
is a non-polymer component).    The  goal of this scheme was to
economize
the specification of polymeric bonding,  representing only a discrete
number of linkage types.   If you feel that the enumeration of this item

is incomplete please advise us of any extensions that you think are
necessary.

Regards,

John


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> Eleanor J.Dodson, Chemistry Department, University of York, U.K.
> Tel: Home +44 (1904) 42 44 49, work:  +44 (1904) 43 25 65
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