Skip to content
Sections
>> Trisquel >> Paquets >> aramo >> science >> kraken2
nabia  ] [  aramo  ]
[ Paquet source : kraken2  ]

Paquet : kraken2 (2.1.2-1)

taxonomic classification system using exact k-mer matches

Kraken 2 is the newest version of Kraken, a taxonomic classification system using exact k-mer matches to achieve high accuracy and fast classification speeds. This classifier matches each k-mer within a query sequence to the lowest common ancestor (LCA) of all genomes containing the given k-mer. The k-mer assignments inform the classification algorithm. [see: Kraken 1's Webpage for more details].

Kraken 2 provides significant improvements to Kraken 1, with faster database build times, smaller database sizes, and faster classification speeds. These improvements were achieved by the following updates to the Kraken classification program:

 1. Storage of Minimizers: Instead of storing/querying entire k-mers,
    Kraken 2 stores minimizers (l-mers) of each k-mer. The length of
    each l-mer must be ≤ the k-mer length. Each k-mer is treated by
    Kraken 2 as if its LCA is the same as its minimizer's LCA.
 2. Introduction of Spaced Seeds: Kraken 2 also uses spaced seeds to
    store and query minimizers to improve classification accuracy.
 3. Database Structure: While Kraken 1 saved an indexed and sorted list
    of k-mer/LCA pairs, Kraken 2 uses a compact hash table. This hash
    table is a probabilistic data structure that allows for faster
    queries and lower memory requirements. However, this data structure
    does have a <1% chance of returning the incorrect LCA or returning
    an LCA for a non-inserted minimizer. Users can compensate for this
    possibility by using Kraken's confidence scoring thresholds.
 4. Protein Databases: Kraken 2 allows for databases built from amino
    acid sequences. When queried, Kraken 2 performs a six-frame
    translated search of the query sequences against the database.
 5. 16S Databases: Kraken 2 also provides support for databases not
    based on NCBI's taxonomy. Currently, these include the 16S
    databases: Greengenes, SILVA, and RDP.

Autres paquets associés à kraken2

  • dépendances
  • recommandations
  • suggestions
  • dep: libc6 (>= 2.34)
    GNU C Library: Shared libraries
    un paquet virtuel est également fourni par libc6-udeb
  • dep: libgcc-s1 (>= 3.3.1) [non armhf]
    GCC support library
    dep: libgcc-s1 (>= 3.5) [armhf]
  • dep: libgomp1 (>= 6)
    GCC OpenMP (GOMP) support library
  • dep: libstdc++6 (>= 11)
    GNU Standard C++ Library v3
  • dep: ncbi-blast+
    next generation suite of BLAST sequence search tools

Télécharger kraken2

Télécharger pour toutes les architectures proposées
Architecture Taille du paquet Espace occupé une fois installé Fichiers
amd64 812,7 ko1620 ko [liste des fichiers]
arm64 807,7 ko1564 ko [liste des fichiers]
armhf 817,5 ko1583 ko [liste des fichiers]
ppc64el 814,5 ko1808 ko [liste des fichiers]