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    • A
      anneng 最后由 编辑

                           The BLAST Databases
                      Last updated on February 3, 2020
      

      IMPORTANT: As of February 4, 2020, the BLAST databases on the FTP site are version 5 (v5).
      At the same time, the databases offered has been changed. This document reflects those changes.
      Information on newly enabled features with the v5 databases at
      https://ftp.ncbi.nlm.nih.gov/blast/db/blastdbv5.pdf

      This document describes the BLAST databases available on the NCBI FTP site under
      the /blast/db directory. The direct URL is ftp://ftp.ncbi.nlm.nih.gov/blast/db

      1. Quick Start

        • Get all numbered files for a database with the same base name:
          Each of these files represents a subset (volume) of that database,
          and all of them are needed to reconstitute the database.
        • After extraction, there is no need to concatenate the resulting files:
          Call the database with the base name, for nr database files, use "-db nr".
        • For easy download, use the update_blastdb.pl script from the blast+ package.
        • Incremental update is not available.
      2. General Introduction

      BLAST search pages under the Basic BLAST section of the NCBI BLAST home page
      (http://blast.ncbi.nlm.nih.gov/) use a standard set of BLAST databases for
      nucleotide, protein, and translated BLAST searches. These databases are made
      available as compressed archives of pre-formatted form) and can be donwloaed from
      the /db directory of the BLAST ftp site (ftp://ftp.ncbi.nlm.nih.gov/blast/db/).
      The FASTA files reside under the /FASTA subdirectory.

      The pre-formatted databases offer the following advantages:
      * Pre-formatting removes the need to run makeblastdb;
      * Species-level taxonomy ids are included for each database entry;
      * Databases are broken into smaller-sized volumes and are therefore easier
      to download;
      * Sequences in FASTA format can be generated from the pre-formatted databases
      by using the blastdbcmd utility;
      * A convenient script (update_blastdb.pl) is available in the blast+ package
      to download the pre-formatted databases.

      Pre-formatted databases must be downloaded using the update_blastdb.pl script or
      via FTP in binary mode. Documentation for this script can be obtained by running
      the script without any arguments; Perl installation is required.

      The compressed files downloaded must be inflated with gzip or other decompress
      tools. The BLAST database files can then be extracted out of the resulting tar
      file using the tar utility on Unix/Linux, or WinZip and StuffIt Expander on
      Windows and Macintosh platforms, respectively.

      Large databases are formatted in multiple one-gigabyte volumes, which are named
      using the basename.##.tar.gz convention. All volumes with the same base name are
      required. An alias file is provided to tie individual volumes together so that
      the database can be called using the base name (without the .nal or .pal
      extension). For example, to call the est database, simply use "-db est" option
      in the command line (without the quotes).

      For other genomic BLAST databases, please check the genomes ftp directory at:
      ftp://ftp.ncbi.nlm.nih.gov/genomes/

      1. Contents of the /blast/db/ directory

      The pre-formatted BLAST databases are archived in this directory. The names of
      these databases and their contents are listed below.

      +-----------------------------+------------------------------------------------+
      File Name | Content Description
      +-----------------------------+------------------------------------------------+
      README | README for this subdirectory (this file)
      nr.tar.gz | Non-redundant protein sequences from GenPept,
      Swissprot, PIR, PDF, PDB, and NCBI RefSeq
      nt.tar.gz | Partially non-redundant nucleotide sequences from
      all traditional divisions of GenBank, EMBL, and DDBJ
      excluding GSS,STS, PAT, EST, HTG, and WGS.
      landmark.tar.gz | Proteome of 27 model organisms, see
      https://blast.ncbi.nlm.nih.gov/smartblast/smartBlast.cgi?CMD=Web&PAGE_TYPE=BlastDocs#searchSets
      16S_ribosomal_RNA | 16S ribosomal RNA (Bacteria and Archaea type strains)
      18S_fungal_sequences.tar.gz | 18S ribosomal RNA sequences (SSU) from Fungi type and reference material (BioProject PRJNA39195)
      28S_fungal_sequences.tar.gz | 28S ribosomal RNA sequences (LSU) from Fungi type and reference material (BioProject PRJNA51803)
      ITS_RefSeq_Fungi.tar.gz | Internal transcribed spacer region (ITS) from Fungi type and reference material (BioProject PRJNA177353)
      ITS_eukaryote_sequences.tar.gz| Internal transcribed spacer region (ITS) for eukaryotic sequences
      LSU_eukaryote_rRNA.tar.gz | Large subunit ribosomal RNA sequences for eukaryotic sequences
      LSU_prokaryote_rRNA.tar.gz | Large subunit ribosomal RNA sequences for prokaryotic sequences
      SSU_eukaryote_rRNA.tar.gz | Small subunit ribosomal RNA sequences for eukaryotic sequences
      ref_euk_rep_genomes
      tar.gz | Refseq Representative Eukaryotic genomes (1000+ organisms)
      ref_prok_rep_genomes
      tar.gz | Refseq Representative Prokaryotic genomes (5700+ organisms)
      ref_viruses_rep_genomestar.gz | Refseq Representative Virus genomes (9000+ organisms)
      ref_viroids_rep_genomes
      tar.gz | Refseq Representative Viroid genomes (46 organisms)
      refseq_protein.*tar.gz | NCBI protein reference sequences
      refseq_rna.*tar.gz | NCBI Transcript reference sequences
      swissprot.tar.gz | Swiss-Prot sequence database (last major update)
      pataa.*tar.gz | Patent protein sequences
      patnt.*tar.gz | Patent nucleotide sequences. Both patent databases
      are directly from the USPTO, or from the EPO/JPO
      via EMBL/DDBJ
      pdbaa.*tar.gz | Sequences for the protein structure from the
      Protein Data Bank
      pdbnt.*tar.gz | Sequences for the nucleotide structure from the
      Protein Data Bank. They are NOT the protein coding
      sequences for the corresponding pdbaa entries.
      taxdb.tar.gz | Additional taxonomy information for the databases
      listed here providing common and scientific names
      FASTA/ | Subdirectory for FASTA formatted sequences
      v4/ | BLAST databases in version 4 (v4). These files are no
      longer being updated.
      cloud/ | Subdirectory of databases for BLAST AMI; see
      http://1.usa.gov/TJAnEt
      +-----------------------------+------------------------------------------------+

      1. Contents of the /blast/db/FASTA directory

      This directory contains FASTA formatted sequence files. The file names
      and database contents are listed below. These files must be unpacked before
      use. They are provided as a convenience for users needing these sets in
      FASTA format. For use with BLAST, it is preferable to use the BLAST database
      on the FTP site.

      +-----------------------+-----------------------------------------------------+
      |File Name | Content Description |
      +-----------------------+-----------------------------------------------------+
      nr.gz* | non-redundant protein sequence database with entries
      from GenPept, Swissprot, PIR, PDF, PDB, and RefSeq
      nt.gz* | nucleotide sequence database, with entries from all
      traditional divisions of GenBank, EMBL, and DDBJ;
      excluding bulk divisions (gss, sts, pat, est, htg)
      and wgs entries. Partially non-redundant.
      pdbaa.gz* | protein sequences from pdb protein structures
      swissprot.gz* | swiss-prot database (last major release)
      +-----------------------+---------------------------------------------------+
      NOTE:
      (1) For screening for vector contamination, use the UniVec database:
      ftp://ftp.ncbi.nlm.nih.gov/pub/UniVec/

      • marked files have pre-formatted counterparts.
      1. Database updates

      The BLAST databases are updated regularly. There is no established incremental
      update scheme. We recommend downloading the complete databases regularly to
      keep their content current.

      1. Non-redundant defline syntax

      The non-redundant databases are nr, nt and pataa. Identical sequences are
      merged into one entry in these databases. To be merged two sequences must
      have identical lengths and every residue at every position must be the
      same. The FASTA deflines for the different entries that belong to one
      record are separated by control-A characters invisible to most
      programs. In the example below both entries Q57293.1 and AAB05030.1
      have the same sequence, in every respect:

      Q57293.1 RecName: Full=Fe(3+) ions import ATP-binding protein FbpC ^AAAB05030.1 afuC
      [Actinobacillus pleuropneumoniae] ^AAAB17216.1 afuC [Actinobacillus pleuropneumoniae]
      MNNDFLVLKNITKSFGKATVIDNLDLVIKRGTMVTLLGPSGCGKTTVLRLVAGLENPTSGQIFIDGEDVTKSSIQNRDIC
      IVFQSYALFPHMSIGDNVGYGLRMQGVSNEERKQRVKEALELVDLAGFADRFVDQISGGQQQRVALARALVLKPKVLILD
      EPLSNLDANLRRSMREKIRELQQRLGITSLYVTHDQTEAFAVSDEVIVMNKGTIMQKARQKIFIYDRILYSLRNFMGEST
      ICDGNLNQGTVSIGDYRFPLHNAADFSVADGACLVGVRPEAIRLTATGETSQRCQIKSAVYMGNHWEIVANWNGKDVLIN
      ANPDQFDPDATKAFIHFTEQGIFLLNKE

      Individual sequences are now identifed simply by their accession.version.

      For databases whose entries are not from official NCBI sequence databases,
      such as Trace database, the gnl| convention is used. For custom databases,
      this convention should be followed and the id for each sequence must be
      unique, if one would like to take the advantage of indexed database,
      which enables specific sequence retrieval using blastdbcmd program included
      in the blast executable package. One should refer to documents
      distributed in the standalone BLAST package for more details.

      1. Formatting a FASTA file into a BLASTable database

      FASTA files need to be formatted with makeblastdb before they can be used in local
      blast search. For those from NCBI, the following makeblastdb commands are
      recommended:

      For nucleotide fasta file: makeblastdb -in input_db -dbtype nucl -parse_seqids
      For protein fasta file: makeblastdb -in input_db -dbtype prot -parse_seqids

      In general, if the database is available as BLAST database, it is better to use the
      preformatted database.

      1. Technical Support

      Questions and comments on this document and NCBI BLAST related questions
      should be sent to the blast-help group at:
      blast-help@ncbi.nlm.nih.gov

      For information about other NCBI resources/services, please send email to
      NCBI User Service at:
      info@ncbi.nlm.nih.gov

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      • A
        anneng 最后由 编辑

        http://arep.med.harvard.edu/seqanal/db.html
        What is Redundancy?
        A key concept in comparing databases is the issue of redundancy. Many databases try to be "non-redundant". Unfortunately, biological data is too complex to fit a simple definition of redundancy. Are two alleles of the same locus redundant? Two isozymes in the same organism? The same locus in two closely related organisms? Hence, each "non-redundant" database has its own definition of redundancy. Some use automated measures, while others use manual culling; the former are amenable to large projects, the latter give higher quality. Other databases don't attempt to be non-redundant, but rather sacrifice this goal in favor of ensuring completeness.
        Databases
        Nucleotide (DNA & RNA)
        nr (NCBI)
        The nr nucleotide database maintained by NCBI as a target for their BLAST search services is a composite of GenBank, GenBank updates, and EMBL updates.
        Non-redundant: Entries with absolutely identical sequences have been merged.
        GenBank / EMBL / DDBJ
        In theory, GenBank, the EMBL Datalibrary, and the DNA Databank of Japan (DDBJ) are just names for the same database. In reality, small timelags in propagating data between the database centers causes minor differences in these databases. However, if one of these libraries is merged with the updates to all of these databases, a complete set of sequences is formed.
        Redundant: Little to no attempts to reduce redundancy
        dbEST (Boguski, Lowe, & Tolstoshev. Nature Genetics 4:332 1993) is a library of Expressed Sequence Tags (Science 252:1651), single-pass cDNA sequences generated from automated sequencers.
        CAUTION: ESTs are blindly sequenced from cDNA libraries with little or no human intervention; they are therefore likely to contain sequencing errors and are frequently contaminated with heterologous sequences and transcribed repetitive elements.

        Redundant: no attempts made to reduce redundancy
        Protein
        nr (NCBI)
        The nr protein database maintained by NCBI as a target for their BLAST search services is a composite of SwissProt, SwissProt updates, PIR, PDB. Entries with absolutely identical sequences have been merged.
        SwissProt
        SwissProt is maintained by Amos Bairoch at the University of Geneva. SwissProt is a highly-curated, highly-crossreferenced, non-redundant database. Unfortunately, the cost of this labor-intensive quality enhancement process is that not every sequence is in SwissProt. If you wish to look up information about a sequence, SwissProt is the first place to look.
        Non-redundant: manual curation used to provide only one entry per protein product; variants are annotated in entry.
        Highly-cross-referenced to other databases.
        PIR
        The Protein Identification Resource was originated by the late Margaret Dayhoff. It attempts to enjoy the advantages of a complete and a non-redundant database.
        Non-redundant: PIR1 section contains only one entry per protein product.
        Redundant: Complete database (PIR1+PIR2+PIR3) has many redundancies
        PDB
        The Protein Data Bank, maintained by Brookhaven National Laboratory (Long Island, New York, USA), contains all publically available solved protein structures. Searches against the pdb can be used to ask whether any known 3D structures are similar to your query protein.
        Non-redundant: Only the "best" determination of a given structure is left in the database; however, multiple structures for one molecule may exist due to other components (i.e. one entry uncomplexed, one complexed).
        OWL
        Prot. Eng. 3:153
        Non-redundant: Automatically generated from component databases (see reference for further info).
        Protein Motifs
        Prosite
        Prosite is a database of protein motifs maintained by Amos Bairoch at the University of Geneva (NAR 19:2241, 1991). Each motif (defined by either a regular expression or a profile) is accompanied by a description of the motif and what is known about it's biology, as well as a listing of the true positive, false negative, and false positive SwissProt entries for the pattern.
        BLOCKS
        BLOCKS is a database developed by Steve Henikoff and colleagues. A block is a gap-free multiple alignment of sequences based on Prosite (Henikoff & Henikoff, NAR 19:6565 1991).

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        • A
          anneng 最后由 编辑

          https://www.ncbi.nlm.nih.gov/books/NBK279670/

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          • A
            anneng 最后由 编辑

            blastdbv5.pdf

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            • A
              anneng 最后由 anneng 编辑

              https://docs.oracle.com/cd/B19306_01/datamine.102/b14340/blast.htm
              Oracle对blast的支持

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              • A
                anneng 最后由 anneng 编辑

                Bioinformatics_ introduction to using BLAST with Ubuntu.pdfBioinformatics_ managing BLAST data sources.pdf

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                • A
                  anneng 最后由 编辑

                  https://dbsloan.github.io/TS2019/exercises/local_blast.html
                  Running Local BLAST and Parsing Output

                  makeblastdb -in Ecoli.proteins.fas -dbtype prot
                  
                  makeblastdb -in Ecoli.genome.fas -dbtype nucl
                  
                  blastn -task blastn  -query Salmonella.genome.fas -db Ecoli.genome.fas -evalue 1e-20 -num_threads 4 -out blastn.txt
                  
                  pdf ("my_dotplot.pdf")
                  plot (blastnData$Query_Start, blastnData$Hit_Start, cex = .25)
                  dev.off()
                  quit()
                  

                  46d8543b-55c2-4680-a439-a6c4129e7baa-image.png

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                  • A
                    anneng 最后由 anneng 编辑

                    Extracting data from BLAST databases with blastdbcmd
                    https://www.ncbi.nlm.nih.gov/books/NBK279689/

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                    • A
                      anneng 最后由 编辑

                      Preformatted BLAST vs Fasta
                      https://www.ncbi.nlm.nih.gov/books/NBK62345/
                      Getting the preformatted database files
                      Preformatted BLAST database files offer several advantages over the FASTA files:

                      The preformatted databases are broken into smaller volumes and therefore can be downloaded more readily with fewer errors
                      A convenient Perl script (update_blastdb.pl found in the bin directory of a locally installed blast+ package) is available to simplify the download of these preformatted databases
                      Preformatted database files remove the makeblastdb formatting steps, and saves valuable processing time and diskspace
                      Taxonomic information is encoded within the preformatted databases and can be used to limit the scope of a blast search, and sequence retrieval, and scientific name addition through the included taxdb files
                      Sequences in FASTA format can be generated easily from the preformatted databases using the blastdbcmd utility when needed

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                      • A
                        anneng 最后由 anneng 编辑

                        Annotating BLAST Reports with Taxonomy Information
                        https://www.mathworks.com/matlabcentral/mlc-downloads/downloads/submissions/15970/versions/2/previews/taxoblastdemo/html/taxoblastdemo.html?access_key=

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                        • A
                          anneng 最后由 编辑

                          https://github.com/lskatz/taxdb
                          一个工具 可以把taxdump导入sqlite

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                          • A
                            anneng 最后由 编辑

                            The BLAST taxonomy database is required in order to print the scientific name, common name, blast name, or super kingdom as part of the BLAST report or in a report with blastdbcmd. The BLAST database contains only the taxid (an integer) for each entry, and the taxonomy database allow BLAST to retrieve the scientific name etc. from a taxid. The BLAST taxonomy database consists of a pair of files (taxdb.bti and taxdb.btd) that are available as a compressed archive from the NCBI BLAST FTP site (ftp://ftp.ncbi.nlm.nih.gov/blast/db/taxdb.tar.gz). The update_blastdb.pl script can be used to download and update this archive; it is recommended that the uncompressed contents of the archive be installed in the same directory where the BLAST databases reside. Assuming proper file permissions and that the BLASTDB environment variable contains the path to the installation directory of the BLAST databases, the following commands accomplish that:

                            Download the taxdb archive

                            perl update_blastdb.pl taxdb

                            Install it in the BLASTDB directory

                            gunzip -cd taxdb.tar.gz | (cd $BLASTDB; tar xvf - )

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                            • Z
                              zhangfanglin 最后由 anneng 编辑

                              nr、nt导出规范

                              **%T %a %i  %t %s**    
                              1、物种ID 
                              2、accession 序列ID           
                              3、sequence title
                              4、描述
                              5、序列
                              

                              上面的导出%i 应该是序列id 我们可以不用这个字段
                              %a %t %T %s

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                              • A
                                anneng 最后由 编辑

                                -outfmt <String>
                                Output format, where the available format specifiers are:
                                %f means sequence in FASTA format
                                %s means sequence data (without defline)
                                %a means accession
                                %g means gi
                                %o means ordinal id (OID)
                                %i means sequence id
                                %t means sequence title
                                %l means sequence length
                                %h means sequence hash value
                                %T means taxid
                                %X means leaf-node taxids
                                %e means membership integer
                                %L means common taxonomic name
                                %C means common taxonomic names for leaf-node taxids
                                %S means scientific name
                                %N means scientific names for leaf-node taxids
                                %B means BLAST name
                                %K means taxonomic super kingdom
                                %P means PIG
                                %m means sequence masking data.
                                Masking data will be displayed as a series of 'N-M' values
                                separated by ';' or the word 'none' if none are available.
                                If '%f' is specified, all other format specifiers are ignored.
                                For every format except '%f', each line of output will correspond
                                to a sequence.
                                Default = `%f'

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                                • A
                                  anneng 最后由 编辑

                                  如果想把一个fasta文件中的序列都当作一个物种对待 那么可以使用taxid参数
                                  合并两个数据库:
                                  makeblastdb -in mysequences.fna -dbtype nucl -title "some sequences I found" -out mysequences -parse_seqids
                                  blastdb_aliastool -dblist nt mysequences -dbtype nucl -title "nt database + my own sequences" -out ntandmore
                                  如果有多个fasta 文件 每个文件是一个物种 可以先分别建库 然后用blastdb_aliastool合并

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