Atom Nomenclature for IUG

The atom nomenclature in PDB data files was revised with the release of data in the PDB Format Version 3.0. These changes make the PDB atom names used by PDB compliant with existing IUPAC nomenclature for standard amino acid and nucleotides (Pure & Appl. Chem., 70, 117-142, 1998) with the exception of the well established convention for C-terminal atoms OXT and HXT. A small number of additional changes were introduced in Version 3 to make atom labeling more conventional. The following chemical diagrams and tables provide the correspondences between atom names used in Version 3 and Version 2 PDB formats.

Labeled Chemical Diagrams

Chemical diagram with format V3 atom labels (heavy atoms)
Chemical diagram with format V3 atom labels (all atoms)
Chemical diagram with format V2 atom labels (heavy atoms)
Chemical diagram with format V2 atom labels (all atoms)

Atom Name Correspondences for IUG

Atom Name (V3) Atom Name (V2)
C1 C1
O1 O1
C2 C2
O2 O2
C3 C3
O3 O3
C4 C4
O4 O4
C5 C5
O5 O5
C6 C6
O6 O6
C1' C1'
C2' C2'
O2' O2'
C3' C3'
O3' O3'
C4' C4'
O4' O4'
C5' C5'
O5' O5'
OAA OAA
OAB OAB
OAC OAC
OAD OAD
OAE OAE
OAK OAK
OAL OAL
OAM OAM
CAN CAN
CAO CAO
CAP CAP
CAQ CAQ
CAR CAR
CAS CAS
CAT CAT
NAW NAW
OBC OBC
CBD CBD
CBE CBE
CBF CBF
CBG CBG
NBQ NBQ
NBR NBR
PBS PBS
PBT PBT
H1 H1
H2 H2
HO2 HO2
H3 H3
HO3 HO3
H4 H4
HO4 HO4
H5 H5
H6 H6
H6A H6A
H1' H1'
H2' H2'
HO2' HO2'
H3' H3'
HO3' HO3'
H4' H4'
H5' H5'
H5'A H5'A
HOAK HOAK
HOAL HOAL
HOAM HOAM
HAN HAN
HAO HAO
HAP HAP
HAQ HAQ
HAR HAR
HAS HAS
HAT HAT
HATA HATA
HNAW HNAW