Atom Nomenclature for MDO

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 MDO

Atom Name (V3) Atom Name (V2)
N1 N
CA1 CA
C1 C1
CB CB
N2 N2
CA2 CA2
C2 C2
O2 O2
CB2 CB2
N3 N3
CA3 CA3
C3 C
O3 O
OXT OXT
H H
H2 H2
HA1 HCA
HB1 HB1
HB2 HB2
HB3 HB3
HB21 HB21
HB22 HB22
HA31 HA31
HA32 HA32
HXT HXT