- Volume 75, Issue 4, 2025

Two Gram-stain-negative, strictly anaerobic, non-motile, non-­spore-forming and rod-shaped bacterial strains, namely, P01024T and P01025T, were isolated from piglet manure. The strains P01024T and P01025T fermented glucose to acetate and butyrate. The major cellular fatty acids (>10.0%) of strain P01024T were C14 : 0, C16 : 0 and summed feature 9 (iso-C17:1 ω9c and/or 10-Methyl-C16:0) and of strain P01025T were C14 : 0, C16 : 0 and summed feature 3 (C16 : 1  ω6c and/or C16 : 1  ω7c). Analysis of 16S rRNA gene sequences indicated that strains P01024T and P01025T belonged to the family Oscillospiraceae. The strain P01024T showed high identities of 16S rRNA genes to type species Flavonifractor plautii ATCC 29863T (96.64%). The highest percentages of conserved protein (POCP) value between strain P01024T and Flavonifractor plautii ATCC 29863T was 59.84%. The average nt identity (ANI) and digital DNA–DNA hybridization (dDDH) values between strain P01024T and Flavonifractor plautii ATCC 29863T were 79.51% and 23.80%, respectively, supporting that strain P01024T represented a novel species of the genus Flavonifractor. Strain P01025T showed high identities of 16S rRNA genes to the type species Flintibacter butyricus BLS21T (95.87%). The highest POCP and AAI (average aa identity) values of strains P01025T to Flintibacter hominis New-19T were 53.02% and 73.11%, respectively. The ANI and dDDH values between strains P01025T and Flintibacter hominis New-19T were 75.44% and 23.40%, respectively, supporting that strain P01025T represented a novel species in the genus Flintibacter. The calculated G+C molar contents for strains P01024T and P01025T were 58.43 and 56.44 mol%, respectively. Together with phenotypic features, we concluded that strains P01024T and P01025T represented novel species in the genera Flavonifractor and Flintibacter of the family Oscillospiraceae, respectively, for which the names Flavonifractor porci sp. nov. (type strain P01024T=CGMCC 1.18055T=KCTC 25793T) and Flintibacter porci sp. nov. (type strain P01025T=CGMCC 1.18060T=KCTC 25794T) are proposed.

Bacterial strain SL12-8T was characterized and isolated from the skin microbiota of Pelophylax perezi, the Perez’s frog. Strain SL12-8T stained Gram-negative and formed rod-shaped cells that grew optimally at 25 °C and pH 7.0–7.5. The G+C content of the DNA was 66.2 mol%. Ubiquinone 8 was the respiratory quinone identified in the studied strain and the most closely related taxon. The major fatty acids were summed in feature 3 and summed in feature 8 and C16:0, representing 84% of the total fatty acids. Phylogenetic analyses based on the 16S rRNA gene sequence placed strain SL12-8T within the order Burkholderiales in a distinct lineage. The 16S rRNA gene sequence similarities of strain SL12-8T to that of Rubrivivax albus, Scleromatobacter humisilvae, Piscinibacter aquaticus, Azohydromonas caseinilytica and Aquincola agrisoli were 94.41, 94.08, 93.72, 93.72 and 93.64%, respectively. The draft genome sequence of strain SL12-8T comprises 3,115,197 bases with a 313-fold mapped genome coverage. The assembled genome consists of 53 large contigs with more than 500 bp, and the genome encodes 2,814 putative coding sequences. The analysis of the available genomes from the closest genera showed 124 core genes that reveal a novel genus-level clade including the strain SL12-8T. Analysis of the SL12-8T genome revealed the presence of the beta-lactone and terpene biosynthetic gene clusters. The phylogenomic, phylogenetic, phenotypic and chemotaxonomic data showed that strain SL12-8T (=UCCCB 131T=CECT 30762T) represents the type of a novel species and genus, for which we propose the name Amphibiibacter pelophylacis gen. nov., sp. nov.

The strain TOYAMA8T is a deep-sea alkaliphilic cellulolytic bacterium isolated from a slurry-adhered epiphytic site of Megalodicopia hians. Cells of this strain are Gram-negative, aerobic, curved rods or spirilla, motile with monopolar flagella, and grow on cellulose as the sole carbon source. Compared to other closely related species, this bacterium is characterized by a large number of cellulase genes. Strain TOYAMA8T showed alkaliphilic growth within the pH range 7.5–9.0. The major cellular fatty acids were C18 : 1 ω7, C14 : 0, C16 : 0 and C16 : 1 ω7. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, unidentified phospholipids and aminolipids. A major respiratory lipoquinone was Q-9. Phylogenomic analysis using the 16S rRNA gene and whole-genome sequence data showed that the strain is related to the families Gynuellaceae, Saccharospirillaceae and Natronospirillaceae. The values of 16S rRNA gene sequence similarity, amino acid identity and percentage of conserved proteins between the strain TOYAMA8T and related species were low, with maximum values of 90.6, 48.1 and 34.6%, respectively. These results, together with differences in phenotypic and biochemical characteristics, indicate that the new isolate TOYAMA8T represents a novel genus and species, for which the name Marinicellulosiphila megalodicopiae gen. nov., sp. nov., is proposed. The type strain is TOYAMA8T (JCM 31119T=DSM 114864T).

A phosphate-solubilizing bacterial strain, designated C3T, was isolated from the rhizosphere of sorghum. The taxonomic classification of this novel isolate was investigated by using a polyphasic approach. Cells of this strain were Gram-stain-negative, facultatively anaerobic and motile short rods with a polar flagellum. Phylogenetic analyses based on the 16S rRNA gene indicated that strain C3T showed high similarity (98.66%) to certain Pantoea species, indicating that the isolate belongs to this genus. The genome of strain C3T was 5.05 Mb in size with a G+C content of 51.1 mol%. Whole-genome analysis revealed that the novel strain shared 21.60–27.10% digital DNA–DNA hybridization values and 78.35–83.87% average nucleotide identity with closely related Pantoea species; both values below the accepted thresholds for defining a novel species. The predominant cellular fatty acids of strain C3T were C16:0, summed feature 3 (C16:1 ω6c and/or C16 :1 ω7c), summed feature 8 (C18: 1 ω7c and/or C18:1 ω6c), summed feature 2 (C12: 0 aldehyde and/or C14:0 3OH and/or C16:1 iso I and/or an unidentified fatty acid of 10.9525 chain length) and C17:0 cyclo. Apart from the ability to solubilize phosphates, stain C3T exhibited other in vitro plant growth-promoting activities such as K, Ca and Si solubilization, and the production of indole-3-acetic acid (IAA) and siderophores. Several genes related to phosphate solubilization, siderophore biogenesis and IAA, cytokinin and gamma-aminobutyric acid production were identified in the C3T genome. Summarizing, based on phylogenetic, genomic, phenotypic and chemotaxonomic criteria, the isolate represents a novel species of the genus Pantoea, for which the name Pantoea phytostimulans sp. nov. is proposed. The type strain is C3T (=CECT 31163T=NCIMB 15596T).

Five strains related to the genus Rodentibacter were isolated from five pet hamsters kept in Japan. Isolates were genotypically and phenotypically distinct from previously described species within the genus Rodentibacter (family Pasteurellaceae). The five strains were the most genetically similar to Rodentibacter haemolyticus 1625-19T, exhibiting a 16S rRNA gene sequence similarity of 96.5%, an average nucleotide identity value of 90.8% and a digital DNA–DNA hybridization value of 42.7%. Phenotypic characteristics further distinguish the isolated strains from other Rodentibacter species. Although they share β-haemolysis capacity with R. haemolyticus, the novel strains are differentiated by their positive reactions for α-glucosidase, l-arabinose and trehalose, as well as negative reactions for β-glucuronidase, mannose, inositol and glycerol. Genotypic and phenotypic differences between the novel strains and closely related known strains suggested that we have identified a new Rodentibacter species. We propose the name Rodentibacter abscessus sp. nov. The type strain is THUN1654T with a G+C DNA content of 40.6 mol%, and it is deposited in the DSMZ Germany (DSM 118002T), KCTC Korea (KCTC 8595T) and JCM Japan (JCM 37054T).

A Gram-stain-negative, aerobic, rod-shaped bacterial strain, SYSU D60014T, was isolated from a sandy soil sample collected from the Gurbantunggut Desert in Xinjiang, PR China. Colonies of SYSU D60014T were pink-coloured, crystalline, irregular edge with a rough surface. Phylogenetic analyses based on both the 16S rRNA gene and whole-genome sequences assigned strain SYSU D60014T belonged to the family Rhodospirillaceae, formed a distinct lineage and showed 92.5–91.0% similarity to closely related strains. Digital DNA–DNA hybridization, average nucleotide identity and average amino acid identity values between strain SYSU D60014T and members of its related species were 17.2–19.6%, 70.8–74.4% and 48.9–64.5%, respectively. The complete genome of strain SYSU D60014T was 5,100,926 bp with a DNA G+C content of 65.1%. Cells were oxidase-positive and catalase-negative. The strain could grow at 28–40 °C (optimum, 37 °C), pH 5.0–8.0 (optimum, pH 7.0), and in the presence of up to 3% NaCl (optimum, 1–1.5%, w/v) on R2A. The predominant menaquinone was Q-10. The main polar lipids were phosphatidylethanolamine, phosphatidylmethyl ethanolamine, diphosphatidylglycerol, unidentified aminophospholipid, unidentified aminolipid, unidentified phospholipid, four unidentified polar lipids and two unidentified phosphoglycolipids. Major cellular fatty acids were C19 : 0 cyclo ω8c, summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c) and C16 : 0. Based on the results obtained through genotypic and phenotypic analyses, we propose that strain SYSU D60014T represents a novel species and genus within the family Rhodospirillaceae, for which we propose the name Virgifigura deserti gen. nov., sp. nov. (type strain SYSU D60014T=NBRC 112951T=CPCC 101030T).

The fungal diversity in environments closely related to human life and health has been largely overlooked. This study describs Ramiconidium sinense gen. et sp. nov., isolated during a survey of soil fungi from Guizhou Wildlife Park in China. A multi-locus phylogenetic analyses demonstrated that Ramiconidium forms a distinct clade (from all previously recognized genera) in the family Microascaceae. R. sinense differs from other taxa of the family by the absence of a sexual state, the absence of anellidic conidiogenous cells, the absence of conidiomata and the production of conidiophores bearing acropetal chains of 0–1-septate conidia. Comprehensive descriptions and detailed illustrations, as well as its taxonomical position based on the analysis of the nucleotide sequences of phylogenetically informative molecular markers, of this are presented in this study.

A novel basidiomycete yeast, designated as NYNU 2211380, was isolated from a leaf of Senecio scandens collected in the Baotianman Nature Reserve, Henan Province, central China. Phylogenetic analyses of the D1/D2 domain of the LSU rRNA gene and the internal transcribed spacer (ITS) region revealed its close relationship to Meniscomyces layueensis, differing by 3.4% mismatches (14 substitutions and 6 gaps) in the D1/D2 domain and 12.4% mismatches (35 substitutions and 37 gaps) in the ITS region. The novel strain also exhibits distinct physiological traits, including an inability to assimilate maltose and cellobiose and the ability to utilize d-xylose, d-ribose, glycerol, ribitol, d-mannitol, dl-lactate and d-gluconate. Based on phylogenetic and phenotypic data, the strain represents a new species in the genus Meniscomyces, for which the name Meniscomyces senecionis sp. nov. (Holotype: CICC 33585; MycoBank: MB 857392) is proposed.