Deinococcus

Deinococcus
A tetrad of D. radiodurans
Scientific classification
Domain:	Bacteria
Phylum:	Deinococcota
Class:	Deinococci
Order:	Deinococcales
Family:	Deinococcaceae Brooks and Murray 1981
Genus:	Deinococcus Rainey et al. 1997
Type species
Deinococcus radiodurans Raj et al. 1960 ex Brooks and Murray 1981
Species
See text.
Synonyms
Deinobacter Oyaizu et al. 1987

Deinococcus (from the Greek: δεινός, deinos, "dreadful, strange" and κόκκος, kókkos, "granule"^[1]) is in the monotypic family Deinococcaceae, and one genus^[2] of three in the order Deinococcales^[3][4] of the bacterial phylum Deinococcota highly resistant to environmental hazards. These bacteria have thick cell walls that give them Gram-positive stains, but they also include a second membrane and are therefore closer in structure to Gram-negative bacteria. Deinococcus survive when their DNA is exposed to high doses of gamma and UV radiation. Whereas other bacteria change their structure in the presence of radiation, such as by forming endospores, Deinococcus tolerate it without changing their cellular form and do not retreat into a hardened structure. They are also characterized by the presence of the carotenoid pigment deinoxanthin that give them their pink color. They are usually isolated according to these two criteria. In August 2020, scientists reported that bacteria from Earth, particularly Deinococcus bacteria, were found to survive for three years in outer space, based on studies conducted on the International Space Station. These findings support the notion of panspermia, the hypothesis that life exists throughout the Universe, distributed in various ways, including space dust, meteoroids, asteroids, comets, planetoids or contaminated spacecraft.^[5][6]