Enrichment cultures of archaea and bacteria performing the anaerobic oxidation of methane (AOM) regularly contain persistent methanogens. Here, we isolated the marine methanogen sp. nov. strain LMO-2 from a long-term AOM enrichment culture from the Northern Gulf of Mexico. Strain LMO-2 is Gram-stain-negative, irregular 0.5-1 µm coccus without flagella. It utilizes a variety of methylated compounds including methanol, monomethylamine, dimethylamine and trimethylamine for growth and methanogenesis. However, it does not grow on formate, acetate, dimethyl sulphate, H/CO, betaine and choline. The optimal conditions for growth were observed within a temperature range of 30-35 °C, a pH range of 7.0-8.0 and a salinity range of 2-4% NaCl. Based on the similarity and phylogeny of the 16S rRNA gene and genomic sequence, strain LMO-2 is classified within the genus . Among the isolated type strains of the genus, strain LMO-2 exhibited the highest 16S rRNA gene sequence identity with SLH33 (99.4%). The digital DNA-DNA hybridization and average nucleotide identity based on genome sequence showed that strain LMO-2 shared the highest similarity with LMO-1, with values of 27.3% and 83.4%, respectively. In conclusion, we isolated a methylotrophic methanogen from an AOM culture, and the isolated strain LMO-2 represented a novel species of the genus , for which the name sp. nov. is proposed. The type strain is LMO-2 (=CGMCC 1.18051=KCTC 25774).

A Gram-stain-negative, yellow-pigmented, non-flagellated, motile by gliding, aerobic and rod-shaped bacterial strain, designated SM2212, was isolated from intertidal sediment of Aoshan Bay in Qingdao, China. The strain grew at 5-35 °C and with 0.5-5.5% NaCl (w/v). It was able to reduce nitrate to nitrite and hydrolyse starch, gelatin and DNA. The phylogenetic trees based on the 16S rRNA genes and single-copy genes showed that strain SM2212 belonged to the genus within the family , sharing the highest 16S rRNA gene sequence similarity with the type strain of (97.1%) and 96.2-97.0% 16S rRNA gene sequence similarity with those of other known species in the genus. The major cellular fatty acids were summed feature 3 (C and/or C ), iso-C, iso-C3-OH, summed feature 9 (iso-C and/or 10-methyl C) and C. The major polar lipids were phosphatidylethanolamine and an unidentified lipid. The genomic DNA G+C content of strain SM2212 was 37.0 mol%. The digital DNA-DNA hybridization and average nucleotide identity values between strain SM2212 and type strains of closely related known species were below 22.2 and 79.7%, respectively. Based on the polyphasic taxonomic analysis in this study, strain SM2212 is considered to represent a novel species in the genus , for which the name is proposed. The type strain is SM2212 (=KCTC 92980=MCCC 1K07684).

Understanding the characteristics of microbes during long-term space missions is essential for safeguarding the health of astronauts and maintaining the functionality of spacecraft. In this study, a Gram-positive, aerobic, spore-forming, rod-shaped strain JL1B1071 was isolated from the surface of hardware on the China Space Station. This strain belongs to the genus , with its closest relative being ATCC 4513. The genome of JL1B1071 is 5 166 230 bp in size, with a G+C content of 35.6 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between JL1B1071 and ATCC 4513 are 83.3 and 27.5%, respectively, both below the recommended thresholds for species delineation. The major cellular fatty acids were anteiso-C and iso-C. The major quinone was menaquinone-7 (MK-7). Notably, strain JL1B1071 demonstrates a unique ability to hydrolyse gelatin, suggesting that it can utilize gelatin as a substrate in nutrient-limited environments. Genomic analysis of JL1B1071 revealed two conserved signature indels in the GAF domain-containing protein and DNA ligase D protein, which are specific to the genus . Additionally, structural and functional differences in proteins BshB1 and SplA were identified, which may enhance biofilm formation, oxidative stress response and radiation damage repair, thereby aiding its survival in the space environment. Based on phenotypic, physiological and chemotaxonomic characteristics, as well as genome annotation, strain JL1B1071 was considered a novel species within the genus and is proposed to be named sp. nov. The type strain is JL1B1071 (=GDMCC 1.4642=KCTC 43715).

A motile, rod-shaped and anaerobic strain WK13 was isolated from a secondary root canal infection of a human tooth. WK13 cells were Gram-stain-negative, catalase-positive and oxidase-negative. The major fatty acids (≥ 5.0%) were C, C, C 7c, C 9c and C 6,9c. The DNA G+C content was 57.94 mol%. The major polar lipids were phosphatidylethanolamine, phosphatidylserine, diphosphatidylglycerol, phosphatidylcholine and lysophosphatidylcholine. There were no respiratory quinones detectable. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain WK13 belongs to the class . WK13 showed a 93.6% and 93.5% 16S rRNA gene sequence similarity to the most closely related cultured species, strain DSM 12018 and strain DSM 5885, respectively. On the basis of physiological and biochemical data, the isolate is considered to represent a novel species of a new genus in the class a, for which we propose the name gen. nov., sp. nov. The type strain is WK13 (=DSM 112713=NCTC 14938).

This study describes a Gram-stain-negative, rod-shaped, facultatively anaerobic bacterial species isolated from the octocoral sp. inhabiting the live coral aquarium at Oceanário de Lisboa in Portugal. Four strains, NE35, NE40, NE41 and NE43, were classified into the genus by means of 16S rRNA gene and whole-genome sequence homologies. We then performed phylogenetic, phylogenomic and biochemical analyses to examine their novel species status within the genus, based on comparisons with the designated novel type strain NE40. The closest 16S rRNA gene relatives to strain NE40 are CL-33 (98.2%), EF212 (97.6%) and PS125 (97.2%). The four strains show genome-wide average nucleotide identity scores above the species level cut-off (95%) with one another and below the cut-off with all type strains with publicly available genomes. Digital DNA-DNA hybridization further supported the classification of the strains as a novel species, showing values below 70% when compared with other type strains. The DNA G+C content of NE40 was 49.0 mol%, and its genome size was 5.45 Mb. Strain NE40 grows from 15 to 37 °C, with 1-5% (w/v) NaCl, and between pH 6.0 and 8.0 in marine broth and shows optimal growth at 28-32 °C, 2-3% NaCl and pH 7.0-8.0. The predominant cellular fatty acids are summed feature 3 (C ω6 and/or C ω7), summed feature 8 (C ω6 and/or C ω7), C and C. Strain NE40 presents oxidase, catalase and -galactosidase activities and can reduce nitrates to nitrites and degrade cellulose, chitin, agarose and xylan. Based on the polyphasic approach employed in this study, we propose the novel species name sp. nov. (type strain NE40=DSM 118084=UCCCB 212).

A taxonomic study was conducted on four bacterial strains isolated from the soil of a coking plant. Phylogenetic analysis showed that the four strains belonged to three families: , and . Identification of the 16S rRNA gene exhibited that their sequence similarities were between 94.96 and 98.98% when compared to known and validly nominated species. Their genomes ranged from 3.4 to 7.2 Mb, with DNA G+C molar contents varying from 62.3 to 67.2%. The average nucleotide identities ranged from 71.4 to 92.3%, and digital DNA-DNA hybridization values were 19.7-47.0% when comparing them with closely related type species, supporting the classification of these four strains. Functional analysis demonstrated that strain H3Y2-7 was robustly resistant to chromate (VI) and arsenite (III) and was able to grow on aromatic compounds including naphthalene as carbon sources even in the presence of chromate (VI). These features reflect its ability to treat combined pollutants and adapt to a polluted environment. Based on the analysis of polyphasic taxonomy, we propose the four bacterial strains representing novel species, namely sp. nov. (type strain H39-3-26=JCM 36178=CGMCC 1.61344), sp. nov. (type strain H3M7-6=JCM 36176=CGMCC 1.61336), sp. nov. (type strain H3Y2-7=JCM 36482=CGMCC 1.61323) and gen. nov., sp. nov. (type strain H3SJ34-1=JCM 36465=CGMCC 1.61333).

Four yeast strains belonging to the ascomycetous yeast genus were isolated from the mixture of remnants of steamed sorghum, Daqu powder and the fermented grain that fell off during transportation on the ground in the workshop which were collected in Xinghuacun Fenjiu old workshop, Shanxi province, PR China. We propose the name sp. nov. (holotype: strain CGMCC 2.7787) for the new species, which differs phenotypically from the other three species in this genus: , and by its ability to grow at 37 °C. This study represents the first isolation of species within the borders of China and the initial report of the species detailing the isolation from the Baijiu brewing environment.

An anaerobic isolate, designated me31, was isolated from pit mud in Yibin, Sichuan Province, PR China. Phylogenetic results based on 16S rRNA gene sequence showed that strain me31 belongs to the family , and the most closely related isolated relatives were SYSU GA16112 (93.65%) and JNU-WLY501 (93.22%). The DNA G+C content was 44.26 mol%. The ANI and AAI values between strain me31 and the closely related strains were 69.25-71.18% and 69.59-71.15%, respectively. Cells of strain me31 were Gram-stain-negative, rod-shaped and non-motile. Growth of strain me31 was observed at 25-37 °C, pH 6.0-8.0 and a salt tolerance range of 0-1.0% (w/v). The predominant respiratory quinone was MK-9. The major fatty acids were anteiso-C, anteiso-C and C 2OH. The polar lipids of strain me31 were found to consist of phosphatidylethanolamine, three unidentified phospholipids, three unidentified phosphoglycolipids, one unidentified phosphoglycolipid, one unidentified lipid, two unidentified glycolipids and one aminophosphoglycolipid. According to the results of morphological, physiological, biochemical, chemotaxonomic, genotypic and phylogenetic analysis, strain me31 represents a novel species of a novel genus of the family , for which the name gen. nov., sp. nov. is proposed. The type strain is me31 (=GDMCC 1.4237=KCTC 25756=WMCC 10035).

Gram-stain-negative, strictly aerobic bacterium, designated strain 2208YS6-2-32, was isolated from a marine invertebrate, () collected by trawl in the south coastal sea of the Republic of Korea. The cells were motile, short-rod, non-spore-forming and contained carotenoid pigments. Catalase and oxidase activities were positive. According to phylogenetic analysis based on 16S rRNA gene and whole-genome sequence determined that strain 2208YS6-2-32 belongs to the novel species and shares the highest 16S rRNA gene similarity with 85 (97.5%). The average nucleotide identity and digital DNA-DNA hybridization values between strain 2208YS6-2-32 and 85 were 78.3% and 21.9%, respectively. The DNA G+C content was 64.5%. Optimal growth of strain 2208YS6-2-32 was observed at 28 °C and pH 8 and in the presence of 1-3% (w/v) NaCl. Strain 2208YS6-2-32 contained ubiquinone-10 as the respiratory quinone, C ω (79.0%) and summed feature 3 (C 7 and/or C ω6c; 13.5%) as the major fatty acids. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified aminolipid and seven unidentified lipids. Based on the results of the polyphasic approach, strain 2208YS6-2-32 represents a novel species of the genus , for which the name sp. nov. is proposed. The type strain is 2208YS6-2-32 (=KACC 23586=JCM 36703).

Two motile bacterial strains, designated as cfHf56-1 and SW 252, were isolated from the coelomic fluid of and from the surrounding seawater at the animal sampling site, respectively. The sea cucumber was collected in the Glénan archipelago (Brittany, France). Strains cfHf56-1 and SW 252 were Gram-stain-negative, non-spore-forming and rod-shaped bacteria. Colonies made on marine agar plates were brown in color. The pH and temperature ranges for growth were 7-8 and 18-30 °C, respectively, in marine broth. The major fatty acids were 16 : 1 cis9 and 16 : 0. Phylogenetic analyses evidenced that both strains belong to a novel species in the genus . The strains were closely related to the type strains of , and with 75-78 % ANI and 19-21 % dDDH values. In this context, cfHf56-1 (= CIP 111854 = CECT 30642) is considered as the type strain of the novel species for which the name sp. nov. is proposed. The genome of the type strain is characterized by a size of 5.1 Mbp and a G+C content of 40.5%.

A Gram-negative, rod-shaped and light pink-pigmented bacterial strain, designated Amp-Y-6, was isolated from the culture of a dinoflagellate CCMP1314. It can produce bacteriochlorophyll . The 16S rRNA gene of strain Amp-Y-6 had the highest sequence similarity with CCMM001 of 98.1%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain Amp-Y-6 was affiliated to the genus and formed a monophyletic clade with CCMM001 and ML6. The digital DNA-DNA hybridization, average nucleotide identity and average amino acid identity between strain Amp-Y-6 and the two phylogenetic relatives were 22.7-22.8, 80.4-80.5 and 79.5-80.2%, respectively. The respiratory quinone was Q-10. The major fatty acid composition was summed feature 8 (C and/or C ). The draft genome size was 3.8 Mbp with a genomic G+C content of 68.1 mol%. Gene annotation showed that Amp-Y-6 contained a gene cluster responsible for the C-P degradation, indicating that it had the potential to provide a phosphate source for the dinoflagellate. Based on the phylogenetic, phenotypic and chemotaxonomic characteristics, strain Amp-Y-6 represents a novel species, for which the name sp. nov. is proposed. The type strain is Amp-Y-6 (=MCCC 1K08249=KCTC 92882).

Three novel strains, designated LB3P45, LS2P90 and ZS1P70, were isolated from glaciers located on the Tibetan Plateau, PR China. These strains were Gram-stain-negative, aerobic, rod-shaped and yellow or orange coloured. Phylogenetic analysis based on the 16S rRNA gene and genomic sequences indicated that they belong to the genus . The 16S rRNA gene sequence similarity among the three strains ranged from 97.4 to 98.6%. Strain LB3P45 showed 98.9% and 98.7% similarity to CGMCC 1.9230 and JCM 11314, respectively. Strain LS2P90 displayed 99.0% and 98.7% similarity to JCM 11314 and CGMCC 1.9230. Strain ZS1P70 had the highest sequence similarity with JCM 11314 (98.0%) and CGMCC 1.9230 (97.8%). The average nucleotide identity and digital DNA-DNA hybridization values between these strains and their closest relatives were lower than 93.0% and 47.9%, respectively. All three strains contained summed feature 3 (comprising C c and/or C c) as the major fatty acids. Based on phenotypic characteristics, phylogenetic analysis and genotypic data, the three novel species are proposed: sp. nov. (LB3P45=CGMCC 1.11439=NBRC 114819), sp. nov. (LS2P90=CGMCC 1.11685=NBRC 114823) and sp. nov. (ZS1P70=CGMCC 1.24124=NBRC 114829).

Two novel Gram-stain-negative, aerobic, heterotrophic, non-motile bacterial strains, designated as AS3R-12 and PS1R-30, were isolated from freshwater in South Korea. To determine their taxonomic positions, the strains were thoroughly characterized. Genomic analyses, based on 16S rRNA gene and draft genome sequence data, revealed that the two novel isolates, AS3R-12 and PS1R-30, belonged to the genus . AS3R-12 showed the highest 16S rRNA gene similarity (97.7%) with UCT-28. In addition, PS1R-30 showed 97.9% 16S rRNA gene similarity with NBRC 107847. The draft genome of strains AS3R-12 and PS1R-30 consisted of 4 149 275 and 4 969 838 bps, with DNA G+C content of 63.1 and 66.1 mol%, respectively. The average nucleotide identity between two strains and other related species was below 76.2%, and the digital DNA-DNA hybridization values with closely related species were below 20.8%, both lower than the species delineation threshold. Strains AS3R-12 and PS1R-30 contained the ubiquinone Q-10 as the major quinone and displayed a polyamine pattern with spermidine as the predominant polyamine. Additionally, their major fatty acids were characterized by C /C (summed feature 3) and C /C (summed feature 8). The major polar lipids of AS3R-12 and PS1R-30 were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), sphingoglycolipid (SGL) and phosphatidylcholine (PC). Moreover, physiological and biochemical results allowed the phenotypic and genotypic differentiation of strains AS3R-12 and PS1R-30 from their closest and other species of the genus with validly published names. Therefore, AS3R-12 and PS1R-30 represented novel species of the genus , for which the names sp. nov. (type strain AS3R-12=KACC 23096=LMG 32950) and sp. nov. (type strain PS1R-30=KACC 23097=LMG 32951) are proposed.

A Gram-stain-negative, aerobic, rod-shaped, motile and flagellated novel bacterial strain, designated MAHUQ-64, was isolated from the rhizosphere of rice. The colonies were observed to be creamy white-coloured, smooth, spherical and 0.5-1.1 mm in diameter when grown on Reasoner's 2A agar medium for 2 days. Strain MAHUQ-64 was able to grow at 10-40 °C, at pH 5.0-9.5 and in the presence of 0-2.0% NaCl (w/v). The strain was positive for both catalase and oxidase tests. The strain was positive for hydrolysis of l-tyrosine. According to the 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus and is closely related to L3B39 (98.6% sequence similarity) and TTM-24 (98.2%). The novel strain MAHUQ-64 has a draft genome size of 3 827 146 bp (22 contigs), annotated with 3612 protein-coding genes, 74 tRNA and 4 rRNA genes. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain MAHUQ-64 and its closest member L3B39 were 86.5 and 33.4%, respectively. genome mining revealed several biosynthetic gene clusters in the genome of the novel strain MAHUQ-64. The genomic DNA G+C content was determined to be 63.4 mol%. The predominant isoprenoid quinone was ubiquinone-8. The major fatty acids were identified as summed feature 3 (comprising C 7 and/or C 6) and C. Based on dDDH, ANI value, genotypic analysis and chemotaxonomic and physiological data, strain MAHUQ-64 represents a novel species within the genus , for which the name sp. nov. is proposed, with MAHUQ-64 (=KACC 22245=CGMCC 1.19000) as the type strain.

In this article, it is proposed that the Nichols strain of be established as the type strain. was first identified as the causative agent of syphilis in 1905, and the Nichols strain was isolated in 1912 by inoculation of a rabbit with cerebrospinal fluid from a patient with neurosyphilis. The Nichols strain has been maintained by serial passage in rabbits for over a century, and historically most studies of have been conducted using this strain. In recent years, a procedure for continuous culture of in a tissue culture system has been developed, making propagation of this spirochaete easier and hence facilitating research. The Nichols strain has >99% DNA homology with a group of organisms that cause syphilis, bejel/endemic syphilis and yaws in humans, a yaws-like disease in primates and spirochaetosis in rabbits and hares. This group is highly similar in terms of their gene and G+C content, genome synteny, cell morphology, natural dependence on mammalian hosts and ability to cause long-term infections; variation occurs in host range, modes of transmission, aptitude for dissemination, manifestations, congenital infection and geographical distribution. Availability of a type strain will aid in the formal acceptance of subspecies first described in 1984 and supported by recent whole-genome analyses of numerous strains from the -related group.

Three strains, designated as J27, J71 and J72, belonging to the genus , were isolated from stable foams formed in activated sludge wastewater treatment plants (WWTPs) in New South Wales, Australia. Phenotypic and genomic analyses revealed that these strains belong to the family and are closely related to . However, distinct genomic and physiological characteristics, including overall genomic relatedness indices, phylogenomic analysis, genomic metabolic profiles and MALDI-TOF MS (Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry), confirmed their status as a new species.Ecologically, these strains showed a wide metabolic versatility, like enhanced membrane transport systems for amino acids, metals and phosphate, as well as the ability to synthesize mycolic acids, contributing to their hydrophobic nature and involvement in foam stabilization. Their adaptations likely provide a competitive advantage in WWTPs, where they persist in nutrient-rich, metal-laden and foam-stabilizing environments. The species did not present the typical rod-coccus cycle, described previously as a defining characteristic of the genus. Based on their unique genomic, phenotypic and ecological features, we propose the name sp. nov., with strain J71 (JCM 34493, NCIMB 15450) designated as the type strain. Additional strains include J27 (JCM 33914, NCIMB 15449) and J72 (NCIMB 15448).

Strains P94, B95 and R96 were isolated from apparently healthy fragments of the coral , which were resistant to infection, from the reef surrounding Moku o Lo'e in Kāne'ohe Bay, O'ahu, Hawai'i, USA, and were taxonomically evaluated using a polyphasic approach. Phylogenetic and phylogenomic analyses placed strains P94, B95 and R96 within the genus and most closely related to and . Following genome sequencing of strains P94, B95 and R96, the average nt identity and DNA-DNA hybridization comparisons with closely related strains resulted in values that fell below species-level cutoffs. Based on a polyphasic characterization and differences in genomic and taxonomic data, strains P94, B95 and R96 represent novel species, for which the names sp. nov., sp. nov. and sp. nov. are proposed. The type strains are R96 (=DSM 114998=LMG 32870), P94 (=DSM 114996=LMG 32871) and B95 (=DSM 114997=LMG 32872), respectively.

The genus comprises Gram-positive bacteria found in diverse natural environments and is classified in the family within the order . Some species exhibit considerable phylogenetic and taxonomic overlaps, prompting a comprehensive investigation that integrates phylogenetic, phylogenomic and comparative genomic analyses to elucidate the taxonomic status of two species. JCM 3387ᵀ and DSM 44772 shared 16S rRNA gene sequence similarity of 99.9% and digital DNA-DNA hybridization values of 99.8%. Moreover, the average nucleotide identity value for the two species was 99.8%, indicating minimal genomic variation between the two strains. Also, the distribution of carbohydrate-active enzymes and biosynthetic gene clusters predicted to code for secondary metabolites between the two species were almost identical. Data of overall genomic similarity support that Lu 2003 be a later heterotypic synonym of Lavrova and Preobrazhenskaya 1975 (Approved Lists 1980).

Opinion 131 addresses a Request for an Opinion asking the Judicial Commission to conserve the genus name Hauser 1885 (Approved Lists 1980) over its earlier homonym, the protozoan genus name Müller 1786. The Judicial Commission agrees that the later homonym is illegitimate and that the replacement of the prokaryotic name would be undesirable. It is also concluded that Müller 1786 is an objectively invalid name under the . Judicial Opinions 9, 12 and 130 serve as precedents for the conservation of Hauser 1885 (Approved Lists 1980) over Müller 1786. This action is taken here and makes the prokaryotic name legitimate.