Today we are going to delve into the fascinating world of Deinococcota. From its origins to its impact on today's society. Deinococcota has been the object of interest and study in various fields, from science and technology to culture and the arts. Throughout history, Deinococcota has played a fundamental role in people's lives, influencing their beliefs, customs and ways of life. In this article, we are going to explore all facets of Deinococcota, from its meaning to its implications in the contemporary world, offering a complete and detailed view of this very relevant topic. Join us on this journey of discovery and knowledge about Deinococcota.
Deinococcota (synonym, Deinococcus-Thermus) is a phylum of bacteria with a single class, Deinococci, that are highly resistant to environmental hazards, also known as extremophiles.
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 those of gram-negative bacteria.
Taxonomy
The phylum Deinococcota consists of a single class (Deinococci) and two orders:
The Deinococcales include two families (Deinococcaceae andTrueperaceae), with three genera, Deinococcus, Deinobacterium and Truepera.Truepera radiovictrix is the earliest diverging member of the order. Within the order, Deinococcus forms a distinct monophyletic cluster with respect to Deinobacterium and Truepera species. The genus includes several species that are resistant to radiation; they have become famous for their ability to eat nuclear waste and other toxic materials, survive in the vacuum of space and survive extremes of heat and cold.
Though these two groups evolved from a common ancestor, the two mechanisms of resistance appear to be largely independent.
Molecular signatures
Molecular signatures in the form of conserved signature indels (CSIs) and proteins (CSPs) have been found that are uniquely shared by all members belonging to the Deinococcota phylum. These CSIs and CSPs are distinguishing characteristics that delineate the unique phylum from all other bacterial organisms, and their exclusive distribution is parallel with the observed differences in physiology. CSIs and CSPs have also been found that support order and family-level taxonomic rankings within the phylum. Some of the CSIs found to support order level distinctions are thought to play a role in the respective extremophilic characteristics. The CSIs found in DNA-directed RNA polymerase subunit beta and DNA topoisomerase I in Thermales species may be involved in thermophilicity, while those found in Excinuclease ABC, DNA gyrase, and DNA repair protein RadA in Deinococcales species may be associated with radioresistance. Two CSPs that were found uniquely for all members belonging to the Deinococcus genus are well characterized and are thought to play a role in their characteristic radioresistant phenotype. These CSPs include the DNA damage repair protein PprA the single-stranded DNA-binding protein DdrB.
Additionally, some genera within this group, including Deinococcus, Thermus, and Meiothermus, also have molecular signatures that demarcate them as individual genera, inclusive of their respective species, providing a means to distinguish them from the rest of the group and all other bacteria. CSIs have also been found specific for Truepera radiovictrix .
Currently there are 10 sequenced genomes of strains in this phylum.
Deinococcus radiodurans R1
Thermus thermophilus HB27
Thermus thermophilus HB8
Deinococcus geothermalis DSM 11300
Deinococcus deserti VCD115
Meiothermus ruber DSM 1279
Meiothermus silvanus DSM 9946
Truepera radiovictrix DSM 17093
Oceanithermus profundus DSM 14977
The two Meiothermus species were sequenced under the auspices of the Genomic Encyclopedia of Bacteria and Archaea project (GEBA), which aims at sequencing organisms based on phylogenetic novelty and not on pathogenicity or notoriety.
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