Nucisporomicrobium flavum gen. nov., sp. nov., a new member of the family Micromonosporaceae isolated from saline-alkali soil.

A Gram-stain-positive, aerobic actinobacterium, designated strain NEAU-24T, was isolated from saline-alkali soil collected from Daqing City, Heilongjiang Province, PR China. Strain NEAU-24T was found to produce abundant substrate mycelia but no aerial hyphae. The substrate mycelia formed irregular pseudosporangia consisting of nuciform spores, and the surface of the spores was smooth. 16S rRNA gene sequence analysis showed that strain NEAU-24T clustered with Pseudosporangium ferrugineum 3-44-a(19)T, Couchioplanes caeruleus subsp. azureus DSM 44103T and C. caeruleus subsp. caeruleus DSM 43634T within the family Micromonosporaceae and was most closely related to P. ferrugineum 3-44-a(19)T (99.17 %). The strain contained meso-diaminopimelic acid as the cell-wall diamino acid and MK-9(H6) as the menaquinone. The whole cell sugar profile consisted of glucose, galactose, xylose and arabinose. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid, phosphatidylinositol and an unidentified lipid. The major fatty acids were summarized as C16 : 0, C15 : 0, C17 : 0, iso-C16 : 0 and iso-C17 : 0. The low digital DNA-DNA hybridization and average nucleotide identity values could differentiate strain NEAU-24T from its related type strains. The phenotypic, genetic and chemotaxonomic data also indicated that strain NEAU-24T occupied a branch separated from those of known genera in the family Micromonosporaceae. In addition, genomic analysis confirmed that strain NEAU-24T had the potential to produce chitinase. Therefore, strain NEAU-24T represents a novel species of a new genus and species in the family Micromonosporaceae, for which the name Nucisporomicrobium flavum gen. nov., sp. nov. is proposed. The type strain of Nucisporomicrobium flavum is NEAU-24T (=CCTCC AA 2020016T=JCM 33973T).

Cellulomonas triticagri sp. nov., isolated from the rhizosphere soil of wheat (Triticum aestivum L.).

A Gram-positive, motile, rod-shaped and lignin-degrading novel actinomycete, designated strain NEAU-YY56T, was isolated from the rhizosphere soil of wheat (Triticum aestivum L.) collected from Zhumadian, Henan Province, Central China and characterized using a polyphasic approach. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain NEAU-YY56T belonged to the genus Cellulomonas and exhibited 16S rRNA gene sequence similarities of 98.7, 98.2 and 98.1% to Cellulomonas pakistanensis JCM 18755T, Cellulomonas denverensis JCM 14733T and Cellulomonas hominis JCM 12133T, respectively. The whole-cell sugars were glucose, rhamnose and ribose. The peptidoglycan of strain NEAU-YY56T contained ornithine and glutamic acid. The phospholipid profile was found to contain diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside and two unknown glycolipids. The major menaquinone was MK-9(H4). The major fatty acids (> 5.0%) were identified as anteiso-C15:0, C16:0, C14:0 and anteiso-C17:0. Meanwhile, DNA G+C content was 74.7%. The morphological and chemotaxonomic properties of strain NEAU-YY56T were also confirmed the affiliation of the isolate to the genus Cellulomonas. However, physiological and biochemical characteristics indicated that strain NEAU-YY56T can be clearly differentiated from its closest relatives. In addition, the ANI values and dDDH levels between strain NEAU-YY56T and related Cellulomonas species were lower than the accepted threshold value. Therefore, it is concluded that strain NEAU-YY56T represents a novel species of the genus Cellulomonas, for which the name Cellulomonas triticagri sp. nov. is proposed. The type strain is NEAU-YY56T (= DSM 106717T = JCM 32550T).

Nocardia albiluteola sp. nov., a novel lignin-degrading actinobacterium isolated from rhizosphere soil of pumpkin.

A novel lignin-degrading actinobacterium, designated NEAU-G5T, was isolated from pumpkin rhizosphere soil collected from field in Mudanjiang, Heilongjiang Province, northeast China, and characterized using polyphasic approach. The prior 16S rRNA gene sequence similarities and phylogenic analysis showed that strain NEAU-G5T exhibited close phylogenetic relatedness to Nocardia miyunensis NBRC 108239T (98.82 %), Nocardia nova NBRC 15556T (98.75 %), Nocardia jiangxiensis NBRC 101359T (98.68 %) and Nocardia macrotermitis RB20T (98.61 %). Morphological and chemotaxonomic characteristics indicated that strain NEAU-G5T could be assigned to the genus Nocardia. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, an unidentified phospholipid and an unidentified lipid. The predominant menaquinone was MK-8(H4, ω-cycl). The major fatty acids (>10 %) were identified as C16 : 0, C18 : 1 ω9c, 10-methyl C18 : 0 and C18 : 0. Mycolic acids were present. The genomic DNA G+C content of strain NEAU-G5T was 68 mol%. Moreover, based on digital DNA-DNA hybridization and average nucleotide identity values, strain NEAU-G5T could be differentiated from its reference strains. In addition, an azure B plate decolorization test and genomic analysis indicated that strain NEAU-G5T had the ability to degrade lignin. On the basis of polyphasic characteristics, strain NEAU-G5T represents a novel species of the genus Nocardia, with the name Nocardia albiluteola sp. nov. The type strain is NEAU-G5T (=CCTCC AA 2021018T=DSM 110547T).

Streptacidiphilus fuscans sp. nov., a novel actinobacterium isolated from the root of pumpkin (Cucurbita moschata).

A novel acidophilic actinobacterium, designated strain NEAU-YB345T, was isolated from a pumpkin root collected from Mudanjiang, Heilongjiang Province, northeast PR China. Based on 16S rRNA gene sequence similarity and chemotaxonomic and morphological properties, the isolate was assigned to the genus Streptacidiphilus, with the high 16S rRNA gene sequence similarities to Streptacidiphilus melanogenes JCM 16224T (99.2 %), Streptacidiphilus anmyonensis JCM 16223T (99.1 %) and Streptacidiphilus jiangxiensis JCM 12277T (98.7 %). Its cell wall contained ll-diaminopimelic acid as the major diamino acid. Rhamnose, ribose, glucose and galactose were the detected sugars from the whole-cell hydrolysates. The phospholipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified phospholipid. The menaquinones were MK-9(H8) and MK-9(H6). Major fatty acids were C16 : 0, iso-C16 : 0, iso-C15 : 0 and anteiso-C15 : 0. Phylogenetic analysis using 16S rRNA gene and whole-genome sequences placed the strain in distinct clades but within the genus Streptacidiphilus. The DNA G+C content was 71.2 mol%. Based on DNA-DNA relatedness and physiological and biochemical data, the isolate could be distinguished from its closest relatives. Therefore, strain NEAU-YB345T represents a novel species of the genus Streptacidiphilus, for which the name Streptacidiphilus fuscans sp. nov. is proposed. The type strain is NEAU-YB345T (=CCTCC AA 2020030T=JCM 33976T).