Microlunatus nigridraconis sp. nov., an actinobacterium from rhizosphere soil

Microlunatus elymi sp. nov., a novel actinobacterium isolated from rhizospheric soil of the wild plant Elymus tsukushiensis

An actinobacterial strain, designated KUDC0627^T, was isolated from rhizospheric soil that contained Elymus tsukushiensis on the Dokdo Islands, Republic of Korea. Cells were Gram-stain-positive, facultative anaerobic, non-motile and non-endospore-forming cocci. Results of phylogenetic analysis based on 16S rRNA gene sequences indicated that strain KUDC0627^T belongs to the genus Microlunatus and is most closely related to Microlunatus soli DSM 21800^T (98.5 %), Microlunatus endophyticus DSM 100019^T (97.7 %) and Microlunatus ginsengisoli Gsoil 633^T (96.5 %). The average nucleotide identity scores and average amino acid identity values were all below the 95.0 % cut-off point. In silico DNA-DNA hybridization, using the Genome-to-Genome Distance Calculator, estimated that there is 22.3 % DNA relatedness between KUDC0627^T and M. soli DSM 21800^T. The genomic DNA G+C content was 66.9 mol%. The major menaquinone was MK-9(H₄) and the major diagnostic diamino acid in the cell-wall peptidoglycan was ll-diaminopimelic acid. The polar lipid profile included diphosphatidylglycerol, phosphatidylglycerol, unidentified phospholipids, unidentified glycolipids and unidentified lipids. The major cellular fatty acids were iso-C_15 : 0, anteiso-C_15 : 0 and iso-C_16 : 0. Based on phenotypic, chemotaxonomic, and phylogenetic data, strain KUDC0627^T (=KCTC 39853^T=JCM 32702^T) represents a novel species, for which the name Microlunatus elymi sp. nov. is proposed.

Prokaryotic names: the bold and the beautiful

In recent years, names of ∼170 new genera and ∼1020 new species were added annually to the list of prokaryotic names with standing in the nomenclature. These names were formed in accordance with the Rules of the International Code of Nomenclature of Prokaryotes. Most of these names are not very interesting as specific epithets and word elements from existing names are repeatedly recycled. The rules of the Code provide many opportunities to create names in far more original ways. A survey of the lists of names of genera and species of prokaryotes shows that there is no lack of interesting names. The annotated selection presented here proves that at least some authors have exploited the possibilities allowed by the rules of the Code to name novel organisms in ways that are more attractive. I here call upon all colleagues who describe new taxa to devote more thought to the naming of new genera and species. It takes some effort, and it requires proper use of the lexicon of Classical Greek and Latin as well as an understanding of the Code and the guidelines of its orthography appendix. Creation of attractive names will boost the general interest in prokaryotic nomenclature.

Microlunatus speluncae sp. nov., a novel actinobacterium isolated from a Karstic subterranean environment sample

A novel actinobacterial strain, designated SYSU K12189^T, was isolated from a soil sample collected from a Karst cave in Xingyi county, Guizhou province, south-western China. The taxonomic position of the strain was investigated using a polyphasic approach. Cells of the strain were observed to be aerobic and Gram-stain positive. On the basis of 16S rRNA gene sequence similarities and phylogenetic analysis, strain SYSU K12189^T is closely related to the type strains of the genus Microlunatus, Microlunatus parietis 12-Be-011^T (98.5% sequence similarity), Microlunatus nigridraconis CPCC 203993^T (98.4%) and Microlunatus cavernae YIM C01117^T (96.6%), and is therefore considered to represent a member of the genus Microlunatus. DNA-DNA hybridization values between strain SYSU K12189^T and related type strains of the genus Microlunatus were < 70%. In addition, LL-diaminopimelic acid was found to be the diagnostic diamino acid in the cell wall peptidoglycan. The major isoprenoid quinone was identified as MK-9(H₄), while the major fatty acids (> 10%) were found to be anteiso-C_15:0, iso-C_15:0, iso-C_16:0 and iso-C_14:0. The polar lipids were found to contain diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, three glycolipids and two unidentified lipids. The genomic DNA G+C content of strain SYSU K12189^T was determined to be 69.4 mol%. On the basis of phenotypic, genotypic and phylogenetic data, strain SYSU K12189^T is concluded to represent a novel species of the genus Microlunatus, for which the name Microlunatus speluncae sp. nov. is proposed. The type strain is SYSU K12189^T (= KCTC 39847^T = DSM 103947^T).