Identifying Microbes in Space

Metagenomics can be used to identify microbes living on the International Space Station by analyzing DNA sequences from environmental samples. The process involves downloading raw DNA data, cleaning it with tools like `fastp`, and then using the `kraken2` algorithm for rapid species classification. `Kraken2` achieves its speed by breaking sequences into smaller k-mers and searching for exact matches in a database, a faster alternative to alignment-based methods like BLAST. Analysis of a sample from the ISS dining table revealed various bacteria and fungi, including a strain associated with kimchi, which was famously brought to the station by a Korean astronaut.