Deinococcus

Deinococcus (from the Greek:δεινός, deinos, "dreadful, strange" and κόκκος, kókkos, "granule") is one genus of three in the Deinococcales group of the Deinococcus-Thermus phylum of bacteria highly resistant to environmental hazards. These bacteria have thick cell walls that give them Gram-positive stains, but they include a second membrane and so are closer in structure to Gram-negative bacteria. Deinococcus survive when their DNA is exposed to high doses of gamma and UV radiation. Where other bacteria change their structure in the presence of radiation, such as endospores, Deinococcus tolerate it without changing their cellular form and do not retreat into a hardened structure. They are also characterised by the presence of the carotenoid pigment deinoxanthin that give them their pink color. Trey is usually isolated according to these two criteria.