ARB Databases

SILVA Release 102: Download the latest ARB databases for small (16S/18S) and large (23S/28S) subunit ribosomal RNAs.

SSU

Ref

   

231 MB 

This is the reference database containing only high quality, aligned 16S/18S ribosomal RNA sequences with a minimum length of 1200 bases for Bacteria and Eukarya and 900 bases for Archaea. A fully classified guide tree is included for fast navigation. For details see release information

HSM

137 MB

This file contains only high quality sequences from the Human Skin Microbiome (not included in SSURef). More information ...

Ref NR

170 MB

This dataset is based on the full Ref dataset (Ref + HSM) by applying a 99% criterion to remove redundant sequences using the Uclust tool. Additionally sequences from cultivated species have been maintained. The final dataset contains 262,092 sequences and can be used as a representative dataset for phylogenetic analysis and classification. More information ...

Parc

703 MB

This is the comprehensive 16S/18S database with all aligned, quality checked rRNA sequences longer than 300 bases and an alignment or sequence quality value above 30.
No tree included, selection of groups can be done based on the EMBL taxonomy.

LSU

Ref

15  MB

This is the reference database containing only high quality, aligned 23S/28S ribosomal RNA sequences with a minimum length of 1900 bases. A fully classified guide tree is included for fast navigation.

Parc

82  MB

This is the comprehensive 23S/28S database with all aligned, quality checked rRNA sequences longer than 300 bases and an alignment or sequence quality value above 30. A guide tree is included for fast navigation.


 

FASTA exports can be found in the file archive

Unpacking the Files

All files for downloading are compressed by tar and gzip. For unpacking use the tar -xzvf <filename> command under Linux or Opens external link in new window winrar under Windows. Please also check if you have sufficient main memory (RAM) available to handle the databases (see box below) and make sure that you have the latest version of ARB installed on your computer.

ARB/SILVA Hardware Requirements

ARB is a so-called "in-memory" database and the larger the databases are, the more main memory (RAM) is required by ARB to handle them. This is by far the main aspect you have to consider when asking for ARB hardware requirements!

The following table will help you to find out more about the ARB hardware requirements for the SILVA rRNA databases which you can download above: ARB/SILVA Memory Requirements (pdf).

Copyright/License Information

Users from non-academic/commercial environments should have a look at the SILVA Terms of Use/License Information