PDB identification code: Difference between revisions

Eric Martz (talk | contribs)
No edit summary
Eric Martz (talk | contribs)
 
(15 intermediate revisions by the same user not shown)
Line 21: Line 21:
For many years, depositors of models could request an available PDB code that represented an acronym for the molecule represented. All the above examples are such cases. With the increase in number of new entries each week, the PDB no longer permits this option. In recent years, all PDB codes are assigned by the PDB from the pool of available codes, in sequential ascending order, without reference to the name of the molecule.
For many years, depositors of models could request an available PDB code that represented an acronym for the molecule represented. All the above examples are such cases. With the increase in number of new entries each week, the PDB no longer permits this option. In recent years, all PDB codes are assigned by the PDB from the pool of available codes, in sequential ascending order, without reference to the name of the molecule.


==PDB codes are permanently associated with a single structure==
==PDB codes have been permanently associated with a single structure==


Once a PDB code is assigned to a given structure, it's forever, even in those cases when a structure is withdrawn (retired from the database), like [[3luw]], or superceded by a newer or corrected structure, like [[1ace]]. If requesting a page for a superseded structure, like [[1aak]], Proteopedia will automatically display the newest structure [[2aak]]. Look for the explanation in the 'About this Structure' section of each page.
Once a PDB code is assigned to a given structure, it's forever, even in those cases when a structure is withdrawn (retired from the database), like [[3luw]], or superceded by a newer or corrected structure, like [[1ace]]. If requesting a page for a superseded structure, like [[1aak]], Proteopedia will automatically display the newest structure [[2aak]]. Look for the explanation in the 'Structural Highlights' section of each page.
 
In May, 2017, the PDB announced plans for a versioning system. This went into effect in July, 2019<ref name="news2" />. It allows multiple versions of the same entry to keep a single PDB code. See [[#Future Plans for Expanded PDB Codes|below]].


==Limited Number of 4-Character PDB Codes==
==Limited Number of 4-Character PDB Codes==


There are 419,904 possible 4-character PDB identification codes<ref>Ten numerals plus 26 letters = 36. The first character is 1-9. (9)(36<sup>3</sup>) = 419,904.</ref>. This could be increased to 466,560 if the numeral "0" is allowed as the first character, but so far there are no plans to do this<ref>In April, 2013. according to Rachel Kramer Green of the RCSB in Rutgers, NJ, there are no plans to use PDB codes beginning with 0.</ref>, Thus, the ~107,000 entries in early 2015 have used up ~25% of the available codes. Someday a scheme that can accommodate more entries will be required, requiring revision of macromolecular visualization and modeling software programs that obtain data online, all of which, of necessity, currently require 4-character PDB codes.
There are 419,904 possible 4-character PDB identification codes<ref>Ten numerals plus 26 letters = 36. The first character is 1-9. (9)(36<sup>3</sup>) = 419,904.</ref>. This could be increased to 466,560 if the numeral "0" is allowed as the first character<ref>In April, 2013. according to Rachel Kramer Green of the RCSB in Rutgers, NJ, there were no plans to use PDB codes beginning with 0. However, in July, 2017, the WWPDB FAQ states "The four-letter PDB identifier currently consists of a number (0-9) followed by 3 letters or numbers.".</ref>. Thus, the ~170,000 entries in mid 2017 (plus withdrawn and superceded entries) have used up nearly half of the available codes. After approximately 2027<ref name="spring2024">[https://cdn.rcsb.org/rcsb-pdb/general_information/news_publications/newsletters/2024q2/deposit.html#two Resources for Supporting the Extended PDB ID Format (pdb_00001abc)], Spring 2024 Issue of the RCSB PDB Newsletter.</ref>, a scheme that can accommodate more entries will be required, requiring revision of macromolecular visualization and modeling software programs that obtain data online, all of which, of necessity, currently require 4-character PDB codes. See plans for an expanded system in the following section.


==Future Plans for Expanded PDB Codes==
==Future Plans for Expanded PDB Codes==
Line 37: Line 39:
In addition to increasing the number of possible accession codes from ~4 x 10<sup>4</sup> to >10<sup>9</sup>, this will facilitate "text mining detection of PDB entries in the published literature"<ref name="news1" />. The PDB also promises "For as long as practicable, the  
In addition to increasing the number of possible accession codes from ~4 x 10<sup>4</sup> to >10<sup>9</sup>, this will facilitate "text mining detection of PDB entries in the published literature"<ref name="news1" />. The PDB also promises "For as long as practicable, the  
wwPDB will continue assigning PDB codes that can be truncated losslessly  
wwPDB will continue assigning PDB codes that can be truncated losslessly  
to the current four-character style."<ref name="news1" />
to the current four-character style."<ref name="news1" /> When 4-character codes are exhausted, new entries will be available in [[Atomic_coordinate_file#mmCIF_Data_Format|mmCIF format]] only, since the legacy [[PDB format]] will not accommodate 12-character IDs.


Along with the expanded accession codes, a versioning system will be introduced<ref name="news1" />.  
In 2024, the [[wwPDB]] plans to make a beta 12-character ID archive available in 2026<ref name="spring2024" />. In 2024, the wwPDB estimates that the 4-character IDs will be consumed in 2029<ref name="spring2024" />.
 
===Versioning===
Along with the expanded accession codes, a versioning system was introduced in mid-2019<ref name="news1" /><ref name="news2">PDB News July 31, 2019: [https://www.rcsb.org/news?year=2019&article=5d3ef68aea7d0653b99c87fd Improve your previously released coordinates AND keep your original PDB ID with OneDep]</ref>.  
<blockquote>
<blockquote>
At present, revised atomic coordinates for an existing released PDB  
At present, revised atomic coordinates for an existing released PDB  
Line 52: Line 57:
</blockquote>
</blockquote>
where "v1" designates a major version, and "-2" a minor version.<ref name="news1" /> "xyz" is a constant that signifies an atomic coordinate file. Other types of data files might use the same PDB accession codes in future.
where "v1" designates a major version, and "-2" a minor version.<ref name="news1" /> "xyz" is a constant that signifies an atomic coordinate file. Other types of data files might use the same PDB accession codes in future.
==Document Object Identifiers (DOI) for PDB Entries==
[http://www.wwpdb.org/news/news?year=2021#607760112786e73a79c76f9d Each PDB entry is accessible through a DOI]. For example, 6ef8 is accessible as [http://doi.org/10.2210/pdb6ef8/pdb doi.org/10.2210/pdb6ef8/pdb].


==See Also==
==See Also==
* [[PDB file format]]
* [[PDB file format]]
* [[User:Eric Martz/Entertaining PDB codes|Entertaining PDB codes]]


==References==
==References==
<references />
<references />

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

Eric Martz, Wayne Decatur, Jaime Prilusky