Hi,
I'm interested in creating a Blast database (makeblastdb) from Uniprot's Bacteria division.
I had to turn to the database release on FTP due to the extremely slow download speed of the website's query results.
So I went to Uniprot's downloads page: http://www.uniprot.org/downloads
Then clicked 'Taxonomic divisions' (or in my case the FTP mirror that is closer to my country): ftp://ftp.ebi.ac.uk/pub/databases/uniprot/current_release/knowledgebase/taxonomic_divisions/
And downloaded these two files:
uniprot_sprot_bacteria.dat.gz
uniprot_trembl_bacteria.dat.gz
Then when I unzipped, I realized these were not Fasta files.
I can't figure out what is their format or how to create a blast database from it.
Any help would be greatly appreciated.
Not sure if you are still interested but maybe it will be useful for someone else who stumbles upon similar thing.
There is a CPAN module for conversion of .dat to .fasta, part of InSilicoSpectro-Databanks
It has few options to explore but you would simply do:
uniprotdata2fasta.pl --in=uniprot_sprot.dat --out=uniprot_sprot.fasta
With this conversion in place you should be good to go for your database generation.
Thanks, but these are not genbank files.
These are UniProt Knowledgebase database files as described here: http://web.expasy.org/docs/userman.html#convent
I think I'll just parse these myself.
The challenge is to use unix pipes (|) to process it from the compressed files all the way to makeblastdb, via sed and/or awk.
I'll post my one-liner once it is done.
I had a look. They are basically genbank files. Here's what I came up with. Line begins with "ID" - print the second column. Line begins with space - print the entire line. Ignore all other lines. Delete spaces.
awk '{if(/^ID/) print ">"$2; else if (/^[[:blank:]]/) print $0}' uniprot_sprot_archaea.dat | tr -d " " > uniprot_sprot_archaea.fasta
Would be more elegant if spaces were deleted in the awk command but whatever.
But maybe you would be more interested in the "AC" (accession) than "ID" lines as templates for fasta headers. I don't know..
Thanks!
I polished it a little:
awk '{if (/^ /) {gsub(/ /, ""); print} else if (/^ID/) print ">" $2}'
So the whole thing looks like this in shell script:
zcat /path/uniprot_{sprot,trembl}_bacteria.dat.gz \
| awk '{if (/^ /) {gsub(/ /, ""); print} else if (/^ID/) print ">" $2}' \
| makeblastdb \
-out /path/uniprot_bacteria \
-dbtype prot -hash_index -title uniprot_bacteria -max_file_sz '50GB'
Newbie question: How do I accept your second comment as the answer?
Another option to convert UniProt text format into FASTA format (with the "official" UniProt FASTA headers):
Install the Swissknife PERL module (http://swissknife.sourceforge.net/docs/) and then run one of the following 2 programs (both do require Swissknife):
1) For a simple fasta conversion that only includes canonical sequences: run the attached script as follows:
perl sp_to_fasta uniprot_bacteria.dat > uniprot_bacteria.fasta
2) For a fasta file that includes alternative isoforms, download ftp://ftp.ebi.ac.uk/pub/software/uniprot/varsplic/varsplic.pl and run it locally, e.g. with a command line such as
perl varsplic.pl -input uniprot_bacteria.dat -check_vsps -crosscheck -error varsplic.err -fasta varsplic_bacteria.fasta -which full
sp_to_fasta:
# Purpose:
# Read a file in SP format, write it in FASTA format.
#
# Usage:
# sp_to_fasta SP_file > FASTA_file
use strict;
use IO::File;
use SWISS::Entry;
my $inputfile = @ARGV[0];
my $fh = new IO::File $inputfile or
die "Cannot open input file $inputfile: $!";
$/ = "\n\/\/";
while(<$fh>) {
s/\r//g;
(my $entry_txt = $_) =~ s/^\s+//;
next unless $entry_txt;
$entry_txt .= "\n";
my $entry = SWISS::Entry->fromText( $entry_txt );
print $entry->toFasta();
}
•
written
by
Elisabeth Gasteiger
You can also try to split your download, for instance to get entries by group of 500:
numentries=XXXX # You have to do a first query on the website to see the number of entries
for I in `seq 0 500 $numentries`; do
wget -O uniprot_$i.fasta "http://www.uniprot.org/uniprot/?sort=score&desc=&compress=no&query=taxonomy:bacteria&fil=&limit=500&force=no&preview=true&format=fasta&offset=$i"
done
To create a query, just do a search on the uniprot website, click on download->preview and copy the URL
•
written
by
Arnaud Ceol
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