Micromonospora tarapacensis sp. nov., a bacterium isolated from a hypersaline lake

Strain Llam7(T) was isolated from microbial mat samples from the hypersaline lake Salar de Llamara, located in Taracapa region in the hyper-arid core of the Atacama Desert (Chile). Phenotypic, chemotaxonomic and genomic traits were studied. Phylogenetic analyses based on 165 rRNA gene sequences assigned the strain to the family Micromonosporaceae with affiliation to the genera Micromonospora and Salinispora. Major fatty acids were C-17:1 omega 8c, iso-C-15:0, iso-C-16:0 and anteiso-C-17:0. The cell walls contained meso-diaminopimelic acid and LL-2,6 diaminopimelic acid (LL-DAP). while major whole-cell sugars were glucose, mannose, xylose and ribose. The major menaquinones were MK-9(H-4) and MK-9(H-6). As polar lipids phosphatidylglycerol, phos-phatidylethanolamine, diphosphatidylglycerol and several unidentified lipids, i.e. two glycolipids, one aminolipid. three phospho-lipids, one aminoglycolipid and one phosphoglycolipid, were detected. Genome sequencing revealed a genome size of 6.894 Mb and a DNA G+C content of 71.4 mol%. Phylogenetic analyses with complete genome sequences positioned strain Llam7(T) within the family Micromonosporaceae forming a distinct cluster with Micromonospora (former Xiangella) phaseoli DSM 45730(T). This cluster is related to Micromonospora pelagivivens KJ-029(T), Micromonospora craterilacus NA12(T), and Micromonospora craniellae LHW63014(T) as well as to all members of the former genera Verrucosispora and Jishengella, which were re-classified as members of the genus Micromonospora, forming a clade distinct from the genus Salinispora. Pairwise whole genome average nucleotide identity (ANI) values, digital DNA-DNA hybridization (dDDH) values, the presence of the diamino acid LL-DAP, and the composition of whole sugars and polar lipids indicate that Llam7(T) represents a novel species, for which the name Micromono-spora tarapacensis sp. nov. is proposed, with Llam7(T) (=DSM 109510(T),=LMG 31023(T)) as the type strain.

Automated summary

Strain Llam7(T) was isolated from the hypersaline lake Salar de Llamara in the Atacama Desert in Chile. Phenotypic, chemotaxonomic, and genomic traits were studied, with the strain belonging to the family Micromonosporaceae. The strain showed differences in fatty acids, cell wall components, whole-cell sugars, and menaquinones. Phylogenetic analysis positioned strain Llam7(T) as a novel species within the genus Micromonospora, forming a distinct cluster with related strains.