Atom Nomenclature for X89

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 X89

Atom Name (V3) Atom Name (V2)
O O
C1 C1
N1 N1
C2 C2
N3 N3
C4 C4
C5 C5
CL2A CL2A
CL2B CL2B
CL4A CL4A
CL4B CL4B
C1A AC1
C1B BC1
C2A AC2
C2B BC2
C3A AC3
C3B BC3
C4A AC4
C4B BC4
C5A AC5
C5B BC5
C6A AC6
C6B BC6
CBA ACB
CBB BCB
H1 H1
H1A H1A
H2 H2
H4 H4
H5 H5
HC3 HC3
HC3A HC3A
HC5 HC5
HC5A HC5A
HC6 HC6
HC6A HC6A
HCB HCB
HCBA HCBA
HCBB HCBB