sp. nov., a novel actinobacterium isolated from Atacama Desert soil.

Three presumptive strains isolated from a high altitude Atacama Desert soil were the subject of a polyphasic study. The isolates, strains 1G4, 1G51 and 1G52, were found to have chemotaxonomic and morphological properties that were consistent with their assignment to the genus . They formed a well supported clade in 16S rRNA gene trees and were most closely related to the type strain of (99.8-99.9% similarity). They were also closely related to the type strains of (99.6 % similarity), (99.7-99.9% similarity), (98.4-99.2% similarity), (99.4-99.5% similarity) and (99.3-99.5% similarity), but were distinguished from their closest relatives by a combination of phenotypic features. Average nucleotide identity and digital DNA:DNA hybridization similarities drawn from comparisons of draft genome sequences of isolate 1G4 and its closest phylogenetic neighbours mentioned above, were well below the threshold used to assign closely related strains to the same species. The close relationship between isolate 1G4 and the type strain of was showed in a phylogenomic tree containing representative strains of family . The draft genome sequence of isolate 1G4 (size 5.18 Kb) was shown to be rich in stress related genes providing further evidence that the abundance of propagules in Atacama Desert habitats reflects their adaptation to the harsh environmental conditions prevalent in this biome. In light of all of these data it is proposed that the isolates be assigned to a novel species in the genus . The name proposed for this taxon is sp. nov., with isolate 1G4 (=DSM 107534=PCM 3003) as the type strain.