_ndb_na_struct_keywds.entry_id               'UDJ031'
    _ndb_na_struct_keywds.conformation_type          B
    _ndb_na_struct_keywds.strand_description     'DOUBLE HELIX'
    _ndb_na_struct_keywds.special_feature         
    ;         FLIPPED-OUT BASES, INTERMOLECULAR BASE TRIPLET
    ;