File Format
The file format initially used by the PDB was called the PDB file format. This original format was restricted by the width of computer punch cards to 80 characters per line. Around 1996, the "macromolecular Crystallographic Information file" format, mmCIF, started to be phased in. An XML version of this format, called PDBML, was described in 2005. The structure files can be downloaded in any of these three formats. In fact, individual files are easily downloaded into graphics packages using web addresses:
- For PDB format files, use, e.g.,
http://www.pdb.org/pdb/files/4hhb.pdb.gz or http://pdbe.org/download/4hhb - For PDBML (XML) files, use, e.g.,
http://www.pdb.org/pdb/files/4hhb.xml.gz or http://pdbe.org/pdbml/4hhb
The "4hhb" is the PDB identifier. Each structure published in PDB receives a four-character alphanumeric identifier, its PDB ID. (This cannot be used as an identifier for biomolecules, because often several structures for the same molecule—in different environments or conformations—are contained in PDB with different PDB IDs.)
Read more about this topic: RCSB
Famous quotes containing the word file:
“While waiting to get married, several forms of employment were acceptable. Teaching kindergarten was for those girls who stayed in school four years. The rest were secretaries, typists, file clerks, or receptionists in insurance firms or banks, preferably those owned or run by the family, but respectable enough if the boss was an upstanding Christian member of the community.”
—Barbara Howar (b. 1934)