Shewanella algae is a rod-shaped Gram-negative marine bacterium.

They can grow on Salmonella-Shigella agar and form yellow-orange or brown colonies.

[2] Shewanella algae is found naturally in wildlife such as certain marine environments but can also exist as a pathogen in humans where they live in soft tissue and produce hemolytic substance or exotoxins.

Humans with Shewanella algae in their system can be immunocompromised.

[3] The ingestion of this algae through raw seafood can cause it to grow in one's soft tissue and develop these neurotoxins which, if left untreated, can cause infections or disease.

[5] Shewanella algae is a facultative anaerobe with the ability to reduce iron, uranium and plutonium metabolically.

Shewanella algae is of great interest to the United States Department of Energy because of its ability to reduce the amount of radioactive waste in groundwater by making it less soluble.