biopython v1.71.0 Bio.Blast.NCBIWWW

Code to invoke the NCBI BLAST server over the internet.

This module provides code to work with the WWW version of BLAST provided by the NCBI. https://blast.ncbi.nlm.nih.gov/

Link to this section Summary

Functions

Extract a tuple of RID, RTOE from the ‘please wait’ page (PRIVATE)

Do a BLAST search using the QBLAST server at NCBI or a cloud service provider

Link to this section Functions

Link to this function _parse_qblast_ref_page()

Extract a tuple of RID, RTOE from the ‘please wait’ page (PRIVATE).

The NCBI FAQ pages use TOE for ‘Time of Execution’, so RTOE is probably ‘Request Time of Execution’ and RID would be ‘Request Identifier’.

Do a BLAST search using the QBLAST server at NCBI or a cloud service provider.

Supports all parameters of the qblast API for Put and Get.

Please note that BLAST on the cloud supports the NCBI-BLAST Common URL API (http://ncbi.github.io/blast-cloud/dev/api.html). To use this feature, please set url_base to ‘http://host.my.cloud.service.provider.com/cgi-bin/blast.cgi’ and format_object=’Alignment’. For more details, please see https://blast.ncbi.nlm.nih.gov/Blast.cgi?PAGE_TYPE=BlastDocs&DOC_TYPE=CloudBlast

Some useful parameters:

  • program blastn, blastp, blastx, tblastn, or tblastx (lower case)
  • database Which database to search against (e.g. “nr”).
  • sequence The sequence to search.
  • ncbi_gi TRUE/FALSE whether to give ‘gi’ identifier.
  • descriptions Number of descriptions to show. Def 500.
  • alignments Number of alignments to show. Def 500.
  • expect An expect value cutoff. Def 10.0.
  • matrix_name Specify an alt. matrix (PAM30, PAM70, BLOSUM80, BLOSUM45).
  • filter “none” turns off filtering. Default no filtering
  • format_type “HTML”, “Text”, “ASN.1”, or “XML”. Def. “XML”.
  • entrez_query Entrez query to limit Blast search
  • hitlist_size Number of hits to return. Default 50
  • megablast TRUE/FALSE whether to use MEga BLAST algorithm (blastn only)
  • service plain, psi, phi, rpsblast, megablast (lower case)

This function does no checking of the validity of the parameters and passes the values to the server as is. More help is available at: http://www.ncbi.nlm.nih.gov/BLAST/Doc/urlapi.html