Confidence is not calculated - does not find the decoys

20 views
Skip to first unread message

Carlo de Oliveira Martins

unread,
Feb 7, 2020, 6:07:57 AM2/7/20
to PeptideShaker
Hi all,

As shown in the attachment, there is no result for protein and peptide confidence in my results.
I am using the latest version of Peptide Shaker (1.16.44) and SearchGUI version 3.3.17 to process data.
My fasta file originally did not contain decoy sequences, so I used the built-in tool from the SearchGUI to add decoys (with the automatic suffix '_REVERSED').
However, when I load the results into a new project, I get a warning that my database contains no decoys, so the confidence will not be calculated.
Any thoughts?
(my first time using this tool, so I may be doing something really dumb)

Thank you,
Carlo



PeptShaker_noConfidence.png

Harald Barsnes

unread,
Feb 7, 2020, 8:46:54 AM2/7/20
to PeptideShaker

Hi Carlo,

It seems like you are using some sort of custom protein sequence database? In that case, it may be that the decoy sequences are not added or picked up correctly.

Have you tried clicking any of the yellow warning icons at the right-hand side of the protein table? This may give you a bit more information about what is going on.

If you are willing to share your database I can always have a closer look as well?

Best regards,
Harald

Carlo de Oliveira Martins

unread,
Feb 7, 2020, 9:04:09 AM2/7/20
to peptide...@googlegroups.com
Hi Harald,

Thanks for your quick response.
This is what I get when clicking on the yellow warning signs:

image.png

You are correct. I am working with a non-Uniprot database (attached here the output from PeptideShaker, with decoys), actually, with more than one, and this is happening with al of them.

Best wishes,
Carlo






--
You received this message because you are subscribed to the Google Groups "PeptideShaker" group.
To unsubscribe from this group and stop receiving emails from it, send an email to peptide-shake...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/peptide-shaker/8b494188-e830-4457-9a03-ee699882c796%40googlegroups.com.
vnz_validated_PeptShaker_decoy.fasta

Carlo de Oliveira Martins

unread,
Feb 7, 2020, 9:06:40 AM2/7/20
to peptide...@googlegroups.com
Sorry, I actually added the wrong database...
NFRAN.2-Proteins_decoy.fasta

Harald Barsnes

unread,
Feb 7, 2020, 9:58:52 AM2/7/20
to PeptideShaker

Hi Carlo,

As expected the problem is the non-standard headers. Please see our help page for how to reformat custom headers in order to make them compatible with PeptideShaker: https://github.com/compomics/searchgui/wiki/DatabaseHelp#non-standard-fasta.

Hopefully a bit of easy search and replace in the target FASTA file should allow you to use the add the decoys in SearchGUI without any errors.

Best regards,
Harald

Carlo de Oliveira Martins

unread,
Feb 7, 2020, 10:42:26 AM2/7/20
to peptide...@googlegroups.com
Thank you!
Best regards

--
You received this message because you are subscribed to the Google Groups "PeptideShaker" group.
To unsubscribe from this group and stop receiving emails from it, send an email to peptide-shake...@googlegroups.com.
Reply all
Reply to author
Forward
0 new messages