Protein Data Bank (PDB)
ATOM/HETATM line Description of the PDB Atom record, ver 2.2:
| Columns | Data type | Field | Definition |
| 1 - 6 | Record name | "ATOM " | |
| 7 - 11 | Integer | serial | Atom serial number. |
| 13 - 16 | Atom | name | Atom name. |
| 17 | Character | altLoc | Alternate location indicator. |
| 18 - 20 | Residue name | resName | Residue name. |
| 22 | Character | chainID | Chain identifier. |
| 23 - 26 | Integer | resSeq | Residue sequence number. |
| 27 | AChar | iCode | Code for insertion of residues. |
| 31 - 38 | Real(8.3) | x | Orthogonal coordinates for X in A. |
| 39 - 46 | Real(8.3) | y | Orthogonal coordinates for Y in A. |
| 47 - 54 | Real(8.3) | z | Orthogonal coordinates for Z in A. |
| 55 - 60 | Real(6.2) | occupancy | Occupancy. |
| 61 - 66 | Real(6.2) | tempFactor | Temperature factor. |
| 73 - 76 | LString(4) | segID | Segment identifier, left-justified. |
| 77 - 78 | LString(2) | element | Element symbol, right-justified. |
| 79 - 80 | LString(2) | charge | Charge on the atom. |
