Devosia aurantiaca sp. nov., Isolated from Mountain Soil and Proposal of Albitalea gen. nov. to Replace the Illegitimate Prokaryotic Genus Name Geomonas Khan et al. 2020

Devosia alba sp. nov., a potential nitrite-reducing bacterium isolated from a mudflat

A Gram-stain-negative, obligately aerobic, motile with polar and lateral flagella and rod-shaped bacterium (1.0-1.5 μm long, 0.4-0.6 μm wide), designated RY10T, was isolated from a mudflat in Zhejiang province, China. Strain RY10T grew at 15-37 °C (optimum 25 °C) and pH 5.0-8.0 (optimum 7.0) and in the presence of 0-4.0% (w/v) NaCl (optimum 2.0-3.0%). Chemotaxonomic analysis indicated that the major respiratory quinone was Q-10, the dominant cellular fatty acids were C16:0, C18:0, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) and summed feature 8 (C18:1 ω7c), and the major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, two unknown phosphoglycolipids and two unknown aminolipids. The DNA G + C content of strain RY10T was 62.3% based on its genomic sequence. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain RY10T formed a distinct lineage within the clade of the genus Devosia. Strain RY10T also exhibit low digital DNA-DNA hybridization (< 70%) and average nucleotide identity values (< 95%) with other Devosia species. Based on the polyphasic taxonomic characterization, strain RY10T is considered to represent a novel species of genus Devosia, for which the name Devosia alba sp. nov. is proposed. The type strain is RY10T (= MCCC 1K03748T = KCTC 72161T).

Ideonella margarita sp. nov., Ideonella lacteola sp. nov., Pseudaquabacterium inlustre sp. nov. and Pseudaquabacterium rugosum sp. nov., isolated from streams in China and re-examining the taxonomic status of all the genera within the family Sphaerotilaceae

Four Gram-stain-negative, aerobic, rod-shaped and motile strains (LYT19WT, DXS22WT, DXS29WT and BYS139WT) were isolated from streams in China. All four strains showed highest 16S rRNA gene sequence similarities to the species of genus Ideonella. The calculated average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values among strains LYT19WT, DXS22WT, DXS29WT, BYS139WT and other closely related strains were less than 79.5, 22.5 and 74.0%, respectively, indicating that each of the four strains should represent an independent novel species. The further reconstructed phylogenomic tree showed that strains LYT19WT and DXS29WT clustered closely with Ideonella strains, but strains DXS22WT and BYS139WT formed an independent clade with Aquabacterium terrae and Aquabacterium pictum. Comparing with other Aquabacterium species, A. terrae and A. pictum harboured distinct physiological and genetic characteristics, so it was reasonable to propose a novel genus Pseudaquabacterium to accommodate A. terrae, A. pictum, DXS22WT and BYS139WT. The major fatty acids of the four strains contained C16 : 0, summed feature 3 (C16 : 1  ω6c and/or C16 : 1  ω7c) and summed feature 8 (C18 : 1  ω6c and/or C18 : 1  ω7c). The predominant polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol and one unidentified aminophospholipid. Combining above descriptions, strains LYT19WT and DXS29WT should represent two novel species of the genus Ideonella, for which the names Ideonella margarita sp. nov. (type strain LYT19WT=GDMCC 1.3205T=KCTC 92545T) and Ideonella lacteola sp. nov. (type strain DXS29WT=GDMCC 1.3207T=KCTC 92547T) are proposed, respectively. Strains DXS22WT and BYS139WT should represent two novel species of the new genus Pseudaquabacterium, for which the names Pseudaquabacterium inlustre sp. nov. (type strain DXS22WT=GDMCC 1.3206T=KCTC 92546T) and Pseudaquabacterium rugosum sp. nov. (type strain BYS139WT=GDMCC 1.3208T=KCTC 92548T) are proposed, respectively.

Devosia rhodophyticola sp. nov. and Devosia algicola sp. nov., isolated from a marine red alga

Two Gram-stain-negative, obligately aerobic, motile rod bacteria, designated as G2-5T and G20-9T, exhibiting catalase- and oxidase-positive activities, were isolated from the phycosphere of a Chondrus species, a marine red alga. Strain G2-5T exhibited optimal growth at 30 °C and pH 5.0-6.0 and in the presence of 0.5-1.0% NaCl. In contrast, strain G20-9T demonstrated optimal growth at 25 °C and pH 6.0 and in the presence of 0.5-1.5% NaCl. Both strains contained ubiquinone-10, summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c), C18 : 0 and 11-methyl-C18 : 1  ω7c, and diphosphatidylglycerol and phosphatidylglycerol as the major respiratory isoprenoid quinone, cellular fatty acids and polar lipids, respectively. The genomic DNA G+C contents were 57.2 mol% for strain G2-5T and 57.5 mol% for strain G20-9T. Strains G2-5T and G20-9T exhibited 98.2 % 16S rRNA gene sequence similarity, along with 82.3 % average nucleotide identity (ANI) and 25.0 % digital DNA-DNA hybridization (dDDH) values, indicating that they represent different species. Phylogenetic analyses based on both 16S rRNA gene and genome sequences revealed that strains G2-5T and G20-9T formed distinct phylogenic lineages within the genus Devosia. Strains G2-5T and G20-9T were most closely related to Devosia limi DSM 17137T and Devosia beringensis S02T with 97.7 and 96.9 % 16S rRNA gene sequence similarities, respectively. The ANI and dDDH values between strains G2-5T and G20-9T and other Devosia species were lower than 73.9 and 19.2 %, respectively, suggesting that they constitute novel species within the genus Devosia. Based on their distinct phenotypic, chemotaxonomic, and molecular characteristics, strains G2-5T and G20-9T represent two novel species of the genus Devosia, for which the names Devosia rhodophyticola sp. nov. (G2-5T=KACC 22601T=JCM 35404T) and Devosia algicola sp. nov. (G20-9T=KACC 22650T=JCM 35405T) are proposed, respectively.

International Committee on Systematics of Prokaryotes, Subcommittee on the taxonomy of Rhizobia and Agrobacteria, minutes of the annual meeting by videoconference, 5 July 2021, followed by online discussion until 31 December 2021

Minutes of the closed meeting of the International Committee on Systematics of Prokaryotes Subcommittee on the Taxonomy of Rhizobia and Agrobacteria held by videoconference, 5 July 2021, followed by online discussion until 31 December 2021, and list of recent species.