Atom Nomenclature for OAS

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 OAS

Atom Name (V3) Atom Name (V2)
N N
CA CA
CB CB
OG OG
C C
O O
C2A C2A
C1A C1A
OAC OAC
OXT OXT
H2 HN2
H H
HA HA
HB2 1HB
HB3 2HB
HC21 1HC2
HC22 2HC2
HC23 3HC2
HXT HXT