Competitive Growth Assay of Mutagenized Chlamydomonas reinhardtii Compatible With the International Space Station Veggie Plant Growth Chamber.

Microalgae are tiny plants, and they can grow by using light from the sun or other sources to turn water and carbon dioxide (CO2) into food. Scientists have been looking at how microalgae could help astronauts live in space for a long time because these little organisms might be able to recycle CO2, which is important since there's not much air up there, and provide them with some of the nutrients they need from plants. In this study, researchers focused on two types of microalgae called CC-5082 (which we can call "the regular one") and a special version named CC-1883 ("with changes"). They wanted to see how these algae would grow in space conditions like low light or small spaces. It turns out that both kinds of algae could do pretty well, even when things are tough for them! The scientists also looked at the genes inside CC-5082 and found some changes (mutations) caused by UV rays-a kind of sunlight with more energy.

This research paper presents an investigation into the growth and adaptability of microalgae strains CC-5082 (WT) and CC-1883 (cw15), which are potential candidates for sustainable life support systems in space. The study's methodology involved using UV mutagenesis to induce non-synonymous mutations, followed by a selection process that identified strains with enhanced purine nucleotide binding and hydrolase activities-key functions related to DNA damage repair and information processing within cells. The key findings of this study revealed significant gene expression changes in both the wild type (WT) CC-5082 and cw15 mutant strains, with enrichments for genes associated with small molecule transporters as well as second messenger signaling pathways. These results suggest that microalgae possess inherent mechanisms to respond adaptively to environmental stressors such as UV radiation-a common challenge in space environments due to the lack of atmospheric protection and exposure to high-energy solar radiation.