SEA-PHAGES Logo

The official website of the HHMI Science Education Alliance-Phage Hunters Advancing Genomics and Evolutionary Science program.

Welcome to the forums at seaphages.org. Please feel free to ask any questions related to the SEA-PHAGES program. Any logged-in user may post new topics and reply to existing topics. If you'd like to see a new forum created, please contact us using our form or email us at info@seaphages.org.

All posts created by debbie

| posted 07 Mar, 2023 16:15
Hi Mitch and students,
I would refer to the structures of phi29 and P68, both of which are prototypes for podoviruses.
https://pubmed.ncbi.nlm.nih.gov/31147544/
https://pubmed.ncbi.nlm.nih.gov/31663016/

Last year, I took a close look at the podovirus PineapplePizza and thought I could apply the terminology of those papers to the gene hits.

I quickly looked at the whole lot of genes in the vicinity and the only one that has a significant hit is 45. BUT, I couldn't quickly discern if it is a tail needle, tail knob, or collar protein. So i would want to think about this. Looking forward to what you come up with!

Rick Pollenz (U of South Florida) and Simon White (U Conn) have worked out some of the structural proteins, finding the major capsid. Check with them to see if they have further identified any other genes.

debbie
Posted in: Functional AnnotationApparent structural proteins from EK2 phage
| posted 06 Mar, 2023 23:43
Tiara,
I can't tell what is gong on. Can they do everything else in DNA Master? Please provide a screen shot of the error.
thanks,
debbie
Posted in: DNA MasterRBS table in PC
| posted 06 Mar, 2023 18:56
Hi! there is some confusing that can be easily remedied.
Syntenically, this gene is positioned to be the capsid maturation protease (CMP).

"The herpesviruses and many phages utilize a maturation protease that acts in this transition from prohead to head, and the main function of the capsid protease is to degrade the parts of the prohead that are required for prohead assembly, but must be removed to complete maturation."
So if we can find it, we want this gene's protein to have some protease function.

The HHPred results hit minor head protein of SPP1, putative capsid assembly protein (likely another way of saying CMP), Phage Mu protein F like - which as per our approved function list is not anything we will call), and gp15 of D29 - which is D29's capsid maturation protease.

Note that all of these are based on inferred calls. I am going to agree with the work of Hatfull and Hendrix, that they were satisfied to call this gene of D29 and L5 a capsid maturation protease some 30 years ago.

I would assign this gene protein the function - capsid maturation protease.

Best,
debbie
Posted in: Cluster EA Annotation TipsEA4 gene 4
| posted 02 Mar, 2023 17:42
Thanks Chris.
Posted in: Functional AnnotationDeep TMHMM?
| posted 27 Feb, 2023 19:20
Hi Amy,
We took Muf-like calls off of the official function list because it appears to not be a structural call and while is appears everywhere, we don't see a good indication of what it is doing. Please do not call it.
Best,
debbie
Posted in: Cluster AK Annotation TipsPortal and MuF-like
| posted 23 Feb, 2023 01:14
Hi Allison,
Minor tail proteins are the most common functional assignments that are acceptable to call with no CDD or HHPred supporting data. The genes that are "eligible" are the 4-6 large genes downstream of tape measure. I would not make the assignment if the gene is not a relatively big gene.
In the case of Kyle's question, there is discrepant data that contradicts a minor tail protein call - synteny and HHPred hits.
Best,
debbie
Posted in: Functional AnnotationRefSeq and INSDC name disagreements in NCBI Blast for Functonal Assignment
| posted 17 Feb, 2023 20:24
Hi Kyle,
Well, this is quite messed up, isn't it.
I will investigate further.
in the meantime, I would like to provide what I think of BLASTp functions calls at NCBI, i don't value them very much - not without supporting evidence. So if you continue to investigate, there is no supporting data for a minor tail protein except NCBI said so. there is no way that a functional call can be made from the blast data that HHPred data sources does not support. (HHPred does a Psi blast, so it is finding more distant relationships to a protein than a single blast could.)
Looks like this is a terminase, small subunit to me.
debbie
Posted in: Functional AnnotationRefSeq and INSDC name disagreements in NCBI Blast for Functonal Assignment
| posted 13 Feb, 2023 13:45
Amanda,
This answer is all about context. I don't know the answer with the information provided. Look at the whole genome. What makes sense? Now that we know that N terminal hits can be signal proteins, i think where in the gene the membrane protein is found impacts my thinking. Just because we moved to Deep THHMM doesn't mean you can't use other tools to continue your evaluation. In general, keep it simple. Membrane proteins are not functions. And when Phamerator gets this in place, the data is not lost.
debbie
Posted in: AnnotationMembrane proteins
| posted 12 Feb, 2023 23:19
Rick,
For now, I would call the big overlap, which I assume is the way that Survivors was called.
Let's continue to consider the Guiding Principles as guidelines.
debbie
Posted in: Cluster CT Annotations TipsBIG GENE OVERLAP
| posted 08 Feb, 2023 03:15
Amanda,
I vote for not calling any TACs.
debbie
Posted in: Cluster B Annotation TipsTail assembly chaperones?