1
$\begingroup$

I am looking at using CD-HIT to efficiently filter my protein sequences dataset by a similarity threshold of 70% (cut-off). More precisely, what I want to achieve is that for all the remaining sequences after filtering, all pairwise sequence similarity scores that can be computed are less than 70%.

Does that mean that I should run CD-HIT on my dataset with similarity threshold=70% (rest of the settings at default values), and then just keep only the "representative" sequences from the resulting cluster files? I have read the guide (http://weizhongli-lab.org/lab-wiki/doku.php?id=cd-hit-user-guide) but I am still not sure of how to use the output.

Linking to the above, how would CD-HIT handle this scenario below or similar ones like this:

  • assuming seq. similarity threshold=70%
  • sim.(seqA, seqB) = 80%
  • sim.(seqA,seqC) = 90%
  • sim.(seqA,seqD) = 65%
  • sim.(seqA, seqE) = 60%
  • sim.(seqD, seqE) = 50%
  • => here, would the method keep just seqE, seqD in the output as sequences satisfying the threshold?

Thanks!

$\endgroup$
1
  • $\begingroup$ I don't follow your question. The sequences seqD and seqE do not fall into the seqA|seqB|seqC cluster, nor do the fall into the same cluster, so you will have three clusters, with the type sequences seqA,seqD and seqE. But that's not your question is it? $\endgroup$ Mar 11, 2021 at 12:58

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Browse other questions tagged or ask your own question.