_struct_sheet.id                sheet_1
    _struct_sheet.type             'beta-barrel'
    _struct_sheet.number_strands    8
    _struct_sheet.details           .
       
    _struct_sheet.id                sheet_2
    _struct_sheet.type             'five stranded, mixed-sense'
    _struct_sheet.number_strands    5
    _struct_sheet.details          'strand_d is in two pieces'