|
Home > |
|
BlastallBlastall may be used to perform all five flavors of blast comparison. One may obtain the blastall options by executing 'blastall -' (note the dash). A typical use of blastall would be to perform a blastn search (nucl. vs. nucl.) of a file called QUERY would be: blastall -p blastn -d /db/ncbiblast/nr -i QUERY -o out.QUERY The output is placed into the output file out.QUERY and the search is performed against the 'nr' database. If a protein vs. protein search is desired, then 'blastn' should be replaced with 'blastp' etc. A more detailed documetn from NCBI is at NCBI. Some of the most commonly used blastall options are: -p Program Name [String] Input should be one of "blastp", "blastn", "blastx",
"tblastn", or "tblastx". -d Database [String] Input could be one of "/db/ncbiblast/nr", "/db/ncbiblast/nt", "/db/ncbiblast/est" or user own database. The database specified must first be formatted with formatdb. Multiple database names (bracketed by quotations) will be accepted. An example would be -d "/db/ncbiblast/nr /db/ncbiblast/est" which will search both the nr and est databases, presenting the results as if one 'virtual' database consisting of all the entries from both were searched. The statistics are based on the 'virtual' database of nr and est. -i Query File [File In] default = stdin The query should be in FASTA format. If multiple FASTA entries are in the input file, all queries will be searched. -e Expectation value (E) [Real] default = 10.0 -o BLAST report Output File [File Out] Optional default = stdout -F Filter query sequence (DUST with blastn, SEG with others) [String] default = T BLAST 2.0 and 2.1 uses the dust low-complexity filter for blastn and seg for the other programs. Both 'dust' and 'seg' are integral parts of the NCBI toolkit and are accessed automatically. If one uses "-F T" then normal filtering by seg or dust (for blastn) occurs (likewise "-F F" means no filtering whatsoever). This options also takes a string as an argument. One may use such a string to change the specific parameters of seg or invoke other filters. Please see the "Filtering Strings" section (below) for details.
-S Query strands to search against database (for blast[nx],
and tblastx).
3 is both, 1 is top, 2 is bottom [Integer]
-T Produce HTML output [T/F]
-l Restrict search of database to list of GI's [String] Optional This option specifies that only a subset of the database should be searched, determined by the list of gi's (i.e., NCBI identifiers) in a file. One can obtain a list of gi's for a given Entrez query from http://www.ncbi.nlm.nih.gov/Entrez/batch.html. This file should be in the same directory as the database, or in the directory that BLAST is called from.
-U Use lower case filtering of FASTA sequence [T/F] Optional
This option specifies that any lower-case letters in the input FASTA file should be masked. Enhancements:A new option has been added to search multiple queries at once for the blastn and tblastn program options of blastall.
-B Number of concatenated queries, for blastn and tblastn [Integer]
Optional This new feature similar in principle, but different in implementation from the support for multiple queries already existing in megablast. The combination of ungapped search (-g F) and multiple queries (-B N) is not supported. The argument to -B option must be equal to the number of sequences in the FASTA input file. Processing multiple query sequences in one run can be much faster than processing them with separate runs because the database is scanned only 1 time for the entire set of queries. When the -B option is used, the results may differ from the ones produced with individual queries. Usually results will be at least as good or better (in terms of score/evalue) than the results of corresponding individual queries; exceptions occur due to the heuristic nature of BLAST. Additional alignments may appear. It is guaranteed that matching sequences will appear in the
same order when they are tied in evalue and are part of the output
both with and without -B. When the -B option is used, the summary
statistics at the bottom of the output are for the combined set
of queries; at present, the summary statistics are not tabulated
for the individual queries in a multiple-query input. The complete arguments for BLASTALL-p : Program Name [String] -d : Database [String] default = nr -i : Query File [File In] default = stdin -e : Expectation value (E) [Real] default = 10.0 -m : alignment view options: 0 = pairwise, 1 = query-anchored showing identities, 2 = query-anchored no identities, 3 = flat query-anchored, show identities, 4 = flat query-anchored, no identities, 5 = query-anchored no identities and blunt ends, 6 = flat query-anchored, no identities and blunt ends, 7 = XML Blast output, 8 = tabular, 9 tabular with comment lines [Integer] default = 0 -o : BLAST report Output File [File Out] Optional default = stdout -F : Filter query sequence (DUST with blastn, SEG with others) [String] default = T -G : Cost to open a gap (zero invokes default behavior) [Integer] default = 0 -E : Cost to extend a gap (zero invokes default behavior) [Integer] default = 0 -X : X dropoff value for gapped alignment (in bits) (zero invokes default behavior) blastn 30, megablast 20, tblastx 0, all others 15 [Integer] default = 0 -I : Show GI's in deflines [T/F] default = F -q : Penalty for a nucleotide mismatch (blastn only) [Integer] default = -3 -r : Reward for a nucleotide match (blastn only) [Integer] default = 1 -v : Number of database sequences to show one-line descriptions for (V) [Integer] default = 500 -b : Number of database sequence to show alignments for (B) [Integer] default = 250 -f : Threshold for extending hits, default if zero blastp 11, blastn 0, blastx 12, tblastn 13 tblastx 13, megablast 0 [Integer] default = 0 -g : Perfom gapped alignment (not available with tblastx) [T/F] default = T -Q : Query Genetic code to use [Integer] default = 1 -D : DB Genetic code (for tblast[nx] only) [Integer] default = 1 -a : Number of processors to use [Integer] default = 1 -O : SeqAlign file [File Out] Optional -J : Believe the query defline [T/F] default = F -M : Matrix [String] default = BLOSUM62 -W : Word size, default if zero (blastn 11, megablast 28, all others 3) [Integer] default = 0 -z : Effective length of the database (use zero for the real size) [Real] default = 0 -K : Number of best hits from a region to keep (off by default, if used a value of 100 is recommended) [Integer] default = 0 -Y : Effective length of the search space (use zero for the real size) [Real] default = 0 -S : Query strands to search against database (for blast[nx], and tblastx) 3 is both, 1 is top, 2 is bottom [Integer] default = 3 -T : Produce HTML output [T/F] default = F -l : Restrict search of database to list of GI's [String] Optional -U : Use lower case filtering of FASTA sequence [T/F] Optional default = F -y : X dropoff value for ungapped extensions in bits (0.0 invokes default behavior) blastn 20, megablast 10, all others 7 [Real] default = 0.0 -Z : X dropoff value for final gapped alignment in bits (0.0 invokes default behavior) blastn/megablast 50, tblastx 0, all others 25 [Integer] default = 0 -R : PSI-TBLASTN checkpoint file [File In] Optional -n : MegaBlast search [T/F] default = F -L : Location on query sequence [String] Optional -A : Multiple Hits window size, default if zero (blastn/megablast 0, all others 40 [Integer] default = 0 -w : Frame shift penalty (OOF algorithm for blastx) [Integer] default = 0 -t : Length of the largest intron allowed in tblastn for linking HSPs (0 disables linking) [Integer] default = 0 |
