Crystallographic Information Framework

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Index

Macromolecular dictionary (mmCIF) version 2.0.09

Category STRUCT_SHEET_ORDER

Name:
'struct_sheet_order'

Description:

   Data items in the STRUCT_SHEET_ORDER category record details
   about the order of the residue ranges that form a beta-sheet.
   All order links are pairwise and the specified pairs are
   assumed to be adjacent to one another in the sheet. These data
   items are an alternative to the STRUCT_SHEET_TOPOLOGY data
   items and they allow all manner of sheets to be described.

Examples:

Example 1 - simple beta-barrel. 
 
    loop_
    _struct_sheet_order.sheet_id
    _struct_sheet_order.range_id_1
    _struct_sheet_order.range_id_2
    _struct_sheet_order.offset
    _struct_sheet_order.sense
     sheet_1  strand_a  strand_b  +1  parallel
     sheet_1  strand_b  strand_c  +1  parallel
     sheet_1  strand_c  strand_d  +1  parallel
     sheet_1  strand_d  strand_e  +1  parallel
     sheet_1  strand_e  strand_f  +1  parallel
     sheet_1  strand_f  strand_g  +1  parallel
     sheet_1  strand_g  strand_h  +1  parallel
     sheet_1  strand_h  strand_a  +1  parallel


Example 2 - five stranded mixed-sense sheet with one two-piece strand. 
 
    loop_
    _struct_sheet_order.sheet_id
    _struct_sheet_order.range_id_1
    _struct_sheet_order.range_id_2
    _struct_sheet_order.offset
    _struct_sheet_order.sense
     sheet_2  strand_a   strand_b    +1 anti-parallel
     sheet_2  strand_b   strand_c    +1 parallel
     sheet_2  strand_c   strand_d1   +1 anti-parallel
     sheet_2  strand_c   strand_d2   +1 anti-parallel
     sheet_2  strand_d1  strand_e    +1 anti-parallel
     sheet_2  strand_d2  strand_e    +1 anti-parallel


Category groups:
    inclusive_group
    struct_group
Category keys:
    _struct_sheet_order.sheet_id
    _struct_sheet_order.range_id_1
    _struct_sheet_order.range_id_2

Mandatory category: no


International Tables for Crystallography

Volume G: Definition and exchange of crystallographic data

First online edition (2006)

Edited by S. R. Hall and B. McMahon

An essential guide and reference to CIF for programmers, data managers handling crystal-structure information and practising crystallographers.