Invalid cvParam accession 200000854

Invalid cvParam accession 200000854 anita liu  2021-05-18


I was trying to create a new Skyline template/file but encountered issues when I was trying to import a "Peptide search" and build a new spectral library. Upon importing the .mzid file and selecting "next", the following message pops up: "ERROR: Invalid cvParam accession "200000854", "ERROR: reading file xxxx.mzid". I had used Protein Metrics Byonic (v4.0.12) software to generate the mzid file, with modifications "Label: 13C(8)15N(2) and 13C(6)15N(2)". I have seen similar cvParam accession number issues in the past and I think it is linked to modifications listed in Protein Metrics when generating the mzid file, but I am not sure why this is the case.

Could you please advise as to what this invalid cvParam accession code refers to, and how to resolve the mzid importing issue?

Thank you!

matt.chambers42 responded:  2021-05-19

That should correspond to UNIMOD:854. I don't see an accession 854 at Can you upload the mzid?

anita liu responded:  2021-05-19

Sure, I've attached the mzid file below. Thank you!

[Edit: file redacted]

matt.chambers42 responded:  2021-05-19

It turns out this UNIMOD accession was deleted sometime between 2014 and 2015. I've sent an email to to ask why. Normally accessions should never be deleted once added, precisely because it causes the problem you've reported here. Can you redo the search without 854, possibly replacing it with a user-defined mod that won't try to map to UNIMOD?

anita liu responded:  2021-05-19

I redid the search removing the two modifications I think are trying to refer to UNIMOD:854 and entered custom modifications instead. This did resolve the accession error. Thank you!