# How can I import an existing Bracken database into QIIME2?

**URL:** https://forum.qiime2.org/t/how-can-i-import-an-existing-bracken-database-into-qiime2/33801
**Category:** User Support
**Tags:** moshpit, metagenomics, import
**Created:** [November 19, 2025, 11:55am UTC](https://forum.qiime2.org/t/how-can-i-import-an-existing-bracken-database-into-qiime2/33801 "2025-11-19T11:55:19Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![ehdud0505](https://forum.qiime2.org/user_avatar/forum.qiime2.org/ehdud0505/32/18591_2.png) [@ehdud0505](https://forum.qiime2.org/u/ehdud0505)
#### Post date: [November 19, 2025, 11:55am UTC](https://forum.qiime2.org/t/how-can-i-import-an-existing-bracken-database-into-qiime2/33801/1 "2025-11-19T11:55:20Z")

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Dear qiime2 teams,

Hi everyone,

My professor has already installed a Kraken2 database on our server, so I am trying to use the existing database instead of building a new one with `kraken2-build` provided by the QIIME2 _mosh_ plugin.

I was able to import the **Kraken2 database** into QIIME2 without any issues.  
However, I cannot import the **Bracken database** — QIIME2 doesn’t seem to recognize the format, and there is no direct importer available.

Is there any way to import an existing **Bracken database** into QIIME2?  
Or does the mosh plugin require that Bracken databases must be generated using its own build workflow?

Any advice or workaround would be greatly appreciated!

Thanks in advance.

Best regards,

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### Author: ![ebolyen](https://forum.qiime2.org/user_avatar/forum.qiime2.org/ebolyen/32/11_2.png) [@ebolyen](https://forum.qiime2.org/u/ebolyen)
#### Post date: [November 19, 2025, 1:10pm UTC](https://forum.qiime2.org/t/how-can-i-import-an-existing-bracken-database-into-qiime2/33801/2 "2025-11-19T13:10:53Z")

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Hello @ehdud0505,

You should be able to import it as a directory if the files resemble this RegEx:

`database(\d{2,})mers\.kmer_distrib$`

You'll just use a standard import command with the type set to `BrackenDB`

```auto
qiime tools import \
  --input-path <your database directory> \
  --output-path db.qza \
  --type 'BrackenDB'

```

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<div class="post-metadata">

### Author: ![ehdud0505](https://forum.qiime2.org/user_avatar/forum.qiime2.org/ehdud0505/32/18591_2.png) [@ehdud0505](https://forum.qiime2.org/u/ehdud0505)
#### Post date: [November 20, 2025, 2:12am UTC](https://forum.qiime2.org/t/how-can-i-import-an-existing-bracken-database-into-qiime2/33801/3 "2025-11-20T02:12:03Z")

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Hi, @ebolyen ,

It's working now.

Thank you so much for your help — I really appreciate it!

Best Regards,

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### Author: ![system](https://forum-qiime2-org.s3.dualstack.us-west-2.amazonaws.com/original/3X/2/1/21af5fe23cb6f4579467c66a9ed94e55274ca7bd.svg) [@system](https://forum.qiime2.org/u/system)
#### Post date: [December 21, 2025, 8:12am UTC](https://forum.qiime2.org/t/how-can-i-import-an-existing-bracken-database-into-qiime2/33801/4 "2025-12-21T08:12:31Z")

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