The wwPDB PDB) provides depositors with detailed reports (PDF and XML files) that include the results of model and experimental data validation, as part of the curation of X-ray crystallographic entries (announcement).
As these wwPDB validation reports provide an assessment of structure quality using widely accepted standards and criteria, the wwPDB partners strongly encourage journal editors and referees to request them from authors as part of the manuscript submission and review process. The reports are date-stamped and display the logo of the wwPDB site where the entry was curated. They contain the same information, regardless of which wwPDB site processed the entry. Provision of wwPDB validation reports is already required by eLife, The Journal of Biological Chemistry, and the International Union of Crystallography (IUCr) journals as part of their manuscript-submission process.
The validation reports continue to be developed and improved as we receive recommendations from the expert Validation Task Forces (VTF) for X-ray, NMR, and EM, as we develop the wwPDB Deposition & Annotation (D&A) system, and as we collect feedback from depositors and users.
A brief User Guide that describes and explains the content of the X-ray validation reports is available. We encourage depositors to submit these validation reports to journals along with their manuscripts.
Please send any comments, questions or suggestions on these new reports to firstname.lastname@example.org
Question 1: What information will be made available about a deposited structure before the coordinates and experimental data are released?
Similar to a typical manuscript submission process (where information is confidential until a paper is published), only limited information is made publicly available prior to release of a PDB entry (see also Question 2).
The validation reports are sent only to the depositors (who may choose to submit them with their manuscripts). They include the results of geometry checks, structure factor validation, and ligand validation. Coordinates and experimental data are not included in the validation report.
Mandatory submission of wwPDB validation reports has not had an impact on the number of submissions to IUCr journals.
Question 2: What is the timing on making information about a deposited structure publicly available? What is the timing for releasing the coordinates, etc.?
The new validation reports are generated for X-ray crystal structures as part of the current wwPDB curation pipelines, and do not affect any timings.
When a structure has been deposited, only the author list, entry title, and release status (along with the pre-release sequence, if allowed by the depositor) are made publicly available with the next weekly PDB update. The entry title may be suppressed by the depositor using the wwPDB Deposition Tool or by request at ADIT-NMR, AutoDep, or EmDep.
Once a PDB entry is finalized and approved by the authors, structures can be released as close to the publication date as our update procedures allow.
Question 3: How much control do authors have over the release of information?
The validation reports are only provided to the depositors, not to journals or other third parties. Depositors thus maintain complete control over the distribution of their validation reports to any journals, co-authors, or other individuals or third parties. Depositors also determine the entry's release status at the time of deposition, typically subject to requirements of the journal in which they aim to publish.
Question 4: I have deposited a structure with the PDB but not received a report. Why not?
The new style validation reports are only provided for new depositions of X-ray crystal structures and subject to the successful completion of the underlying calculations. For instance, no reports are created for NMR or 3DEM structures, and occasionally a software problem may preclude generation of a report for an X-ray structure (we endeavor to fix any such problems as soon as possible, where needed in collaboration with the authors of the software).
Question 5: The validation report only lists up to 5 outliers - what if I want to see more?
In addition to the summary reports in PDF form, wwPDB also provides full reports (PDF, XML) for every entry that contains exhaustive information on all statistics, complete lists of outliers, etc.
Question 6: Can I get a validation report for an existing X-ray structure in the PDB?
In 2014, validation reports (PDF and XML files) for all existing X-ray crystal structures in the PDB archive were made publicly available through the wwPDB ftp sites.
In the future, wwPDB plans to recalculate statistical distributions as well as validation reports for all entries once a year. All these data will be made publicly available to encourage downstream use by software developers, bioinformaticians and other PDB users.
In addition, wwPDB expects to reconvene VTFs once every 5 years or so to assess the validation pipelines, reports and protocols and to recommend any changes, updates or additions.
Question 7: Can I get a validation report for my own intermediate or unpublished structure?
X-ray structure validation reports can now be generated on demand by macromolecular crystallographers using the Validation Server.