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Terminase, large subunit

| posted 23 Aug, 2018 19:55
The terminase, large subunit appears to be in 3 pieces in this cluster (determined when annotating Melons (Cluster AS2). The first piece matches the ATPase domain; the second (though the matches are not obvious - read the paper to understand why) matches the DNA binding domain of the protein); and the third matches the nuclease domain.

| posted 22 Oct, 2019 21:54
terminase, large subunit (ATPase domain) and
terminase, large subunit (nuclease domain)

are both approved functions on the list. But "terminase, large subunit (DNA binding domain)" is not. Can I designate the second gene/piece of the terminase as "terminase, large subunit (DNA binding domain)" in my AS2 phage LittleTokyo?
| posted 23 Oct, 2019 07:00
I believe that gene 2 is the small terminase subunit. As such its function is to form a nucleoprotein structure that helps to position the terminase large subunit at the packaging initiation site. I think that "terminase, small subunit" is sufficient for the label of this gene.
| posted 23 Oct, 2019 14:36
Hi Debbie,

We have located the small subunit of the terminase in the right arm of the genome, as expected based on Melons ( Based on your above comment (and BLAST hits, etc) it does seem like our second gene is some subunit of the large terminase - I'm just not sure which function I should give it specifically.

| posted 23 Oct, 2019 18:25
Hi Amanda,
Debbie and I reviewed the evidence for the small terminase in the right arm of the genome and we don't think it holds up. We will be changing this function call to DNA binding protein or transcription factor, depending on the protein.
| posted 23 Oct, 2019 18:32
Ah, ok! Thank you so much for the update!
| posted 21 Feb, 2020 18:32
I looked carefully at gene one of these too– and although it aligned to the large subunit, the alignment occurs in the middle of the functional domains, possibly interrupting them. SO we will call that gene hypothetical protein for now.
| posted 31 Jul, 2020 19:05
I am currently looking at AS1 phage Brynnie. I am not seeing the calls in the cluster as reflected based on the tips from this forum. Would Brynnie_1 NKF, 2, small terminase subunit, and 3 large terminase subunit be acceptable calls? I am also not seeing any tail spike proteins called.
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