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Plasmids classified as viruses

Open asl opened this issue 4 years ago • 4 comments

Consider the attached FASTA file. It contains two sequences that match a plasmid from RefSeq at 99% IDY. However, there are classified as virus by viralVerify. Looks strange. ic5-metaplasmidspades.plasmid.fasta.zip

asl avatar Nov 16 '20 10:11 asl

Interesting. They both predicted as viruses by other tools, such as VirSorter, and match phages P1 and P7 with IDY 96-98% and span 86%. And this is fine because these phages are somewhat special - they can exist as a plasmids in the cell, and have both plasmid- and phage-specific genetic features.

mikeraiko avatar Nov 17 '20 11:11 mikeraiko

FWIW Platon (https://github.com/oschwengers/platon) predicts it as plasmid.

asl avatar Nov 17 '20 12:11 asl

I'm pretty sure that plasmidVerify would also classify it as plasmid. For the sequences that similar to both P and V and not similar to C a plasmid prediction tool would say they are plasmid, and a viral prediction tool would say they are viral

Current logic for viralVerify is to compare V vs P+C and then only if P+C compare P vs C. It is vulnerable to such cases, but I suppose it is not a common situation..

Dmitry-Antipov avatar Nov 17 '20 12:11 Dmitry-Antipov

And these contigs are plasmids and phages in the same time.

So, the right answer for such contigs should be virus_or_plasmid that is not currently supported by viralverify.

Dmitry-Antipov avatar Nov 17 '20 12:11 Dmitry-Antipov