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Biopython is a collection of python modules that facilitate the development of python scripts for bioinformatics applications. As such, it does not include ready to use programs in the sense that many commercial packages and free web-based interfaces do. On the other hand, Biopython provides reusable python modules that facilitate writing scripts for sequence manipulation, accessing of databases using a range of data formats and execution and parsing of the results of various molecular biology programs. Consequently, Biopython enables developing scripts that can analyze large quantities of sequence data in ways that are typically difficult or impossible with web based systems.


Biopython is free to use and open source. It is dual licensed under Biopython License or BSD 3-Clause License.


In Puhti, Biopython libraries, as well as many other bioinformatics related Python libraries are available in the Python installations that are used by the bioconda environments. These environment also include python virtual environments that allow users to create their own project specific Python environment with pip installation tool.

These virtual environments use the PROJAPPL directory for installing the user specific libraries. Because of that, you must first set PROJAPPL environment variable to point to the PROJAPPL directory of the project you want to use.

export PROJAPPL=/projappl/project_your_proj_num
After that, a virtual Python environment using Python 3.7.3 and biopython can be set up with commands:
module load bioconda
If you want to use old Python 2.7.5 with biopython in stead, use setup commands:

module load bioconda/2
However, we strongly recommend using Python 3 versions in stead of Python 2.

When the virtual environment is activated, you can launch a biopython program with command:

Alternatively you can change the python definition in the first line of your code to
#!/bin/env python
and execute the python program


New python libraries can be installed with pip install command. For example, Python library called OBITools3 could be installed with command:

pip install OBITools3


More information about biopython can be found form the homepage of biopython.

Last update: April 28, 2022