Deinococcus

Deinococcus is a genus of bacteria notable for extraordinary resistance to environmental stress, including ionizing radiation, desiccation, and oxidative stress. Members are typically non-motile, non-spore-forming, and predominantly aerobic. They occur in diverse environments such as soil, fresh water, and dust, where their robust stress tolerance is advantageous.

Deinococcus radiodurans is the best-studied species and serves as a model for radiation resistance. It can survive levels of ionizing radiation that would be lethal to most organisms and can repair extensive DNA damage rapidly, largely restoring genomic integrity after insult.

Genetically, Deinococcus species are notable for large, polyploid genomes with multiple copies per cell, which aids DNA repair by providing templates for homologous recombination. They possess a suite of DNA repair proteins, such as RecA, PprA, DdrA, and DdrB, and rely on manganese-based systems that protect proteins under stress.

Ecology and metabolism: They are chemoorganoheterotrophs, oxidizing organic compounds for energy and carbon; not photosynthetic; generally non-pathogenic and isolated from non-clinical environments.

Applications and significance: The radiation and desiccation tolerance inform astrobiology and DNA repair research. They are explored for bioremediation of radioactive waste and for biotechnological tools in stress tolerance and genome maintenance.

Taxonomy: Deinococcus belongs to the phylum Deinococcota and the family Deinococcaceae. The genus includes several species, with Deinococcus radiodurans as the type species.