Question: Blastp e-value, bit score, identify importance to identify homolog sequences
gravatar for Mehmet
4.2 years ago by
Mehmet670 wrote:

Dear All;

I would like to ask you; which one or ones are more important to identify homolog sequences using blastp?


Bit score?

Identify % ?

I am trying to find homolog sequences of candidate neuropeptides in my database by searching with blast p. I have an output (format 6). I want to filter results, then I will search in Uniprot o blast to identify my candidate proteins as neuropeptides or not. For this, which parameter should I use? Evalue, bit score, identify %, or combine them?

my approach will be to filter sequences which have e-value lower than 0.01 and bit score bigger than 90.

is this reasonable ? or is it possible to miss some neuropeptides.?

Thank you.

blast alignment sequence • 1.6k views
ADD COMMENTlink written 4.2 years ago by Mehmet670

Depends on if you want an identical hit or similar-enough peptides. Whenever I've had to do this kind of work, I've always put more emphasis on columns 4 (Alignment length), 5 (Number of mismatches), and 6 (Number of gap opens) first. Because, as long as alignment length is 100% with 0 mismatch AND 0 gaps, this alignment is the best one. Then you can move down the columns looking for evalue, identity %, etc.

ADD REPLYlink written 4.2 years ago by berge201590
Please log in to add an answer.


Use of this site constitutes acceptance of our User Agreement and Privacy Policy.
Powered by Biostar version 2.3.0
Traffic: 2904 users visited in the last hour