- Volume 75, Issue 1, 2025

An obligately anaerobic, spore-forming sulphate-reducing bacterium, strain SB140T, was isolated from a long-term continuous enrichment culture that was inoculated with peat soil from an acidic fen. Cells were immotile, slightly curved rods that stained Gram-negative. The optimum temperature for growth was 28 °C. Strain SB140T grew at pH 4.0–7.5 with an optimum pH of 6.0–7.0 using various electron donors and electron acceptors. Yeast extract, sugars, alcohols and organic acids were used as electron donors for sulphate reduction. SB140T additionally used elemental sulphur and nitrate as electron acceptors but not sulphite, thiosulphate or iron(III) provided as ferrihydrite and fumarate. The 16S rRNA gene sequence placed strain SB140T in the genus Desulfosporosinus of the phylum Bacillota. The predominant cellular fatty acids were iso-C15 : 0 (52.6%) and 5,7 C15 : 2 (19.9%). The draft genome of SB140T (5.42 Mbp in size) shared 77.4% average nucleotide identity with the closest cultured relatives Desulfosporosinus acididurans M1T and Desulfosporosinus acidiphilus SJ4T. On the basis of phenotypic, phylogenetic and genomic characteristics, SB140T was identified as a novel species within the genus Desulfosporosinus, for which we propose the name Desulfosporosinus paludis sp. nov. The type strain is SB140T (=DSM 117342T=JCM 39521T).

A Gram-stain-positive, facultatively anaerobic, rod-shaped strain, designated SPB1-3T, was isolated from tree bark. This strain exhibited heterofermentative production of dl-lactic acid from glucose. Optimal growth was observed at 25–40 °C, pH 4.0–7.0, and in the presence of 3% (w/v) NaCl. The cell wall peptidoglycan contained lysine and aspartic acid. The predominant fatty acids identified were C16:0 and the Summed feature 7 (C19 :1  ω7c/C19:1  ω6c and/or C19:1  ω6c/ω7c/19cy). The polar lipid profile included phosphatidylglycerol, diphosphatidylglycerol and phosphatidylinositol, along with two unidentified phospholipids, two unidentified amino lipids and two unidentified lipids. Phylogenetic analysis based on 16S rRNA gene sequences positioned strain SPB1-3T within the genus Lentilactobacillus, showing a close relation to Lentilactobacillus kosonis NBRC 111893T (99.86%) and Lentilactobacillus curieae CCTCC M 2011381T (98.65%). The whole genome of strain SPB1-3T comprised 1 932 998 base pairs with 1955 coding genes and a DNA G+C content of 37.8%. Digital DNA–DNA hybridization between strain SPB1-3T and closely related type strains ranged from 19.50 to 27.20%. The average nucleotide identity ranged from 84.21 to 85.56%, and the average amino acid identity ranged from 57.25 to 85.99%, both falling below the established thresholds for species delineation. Strain SPB1-3T was clearly distinguishable from related Lentilactobacillus species based on its phenotypic and chemotaxonomic characteristics, 16S rRNA gene sequence similarity and whole genome analysis. Additionally, the strain exhibited radical scavenging activity at 66.92% and demonstrated 82.32% inhibition in the tyrosinase inhibitory assay. These findings support the classification of strain SPB1-3T as a novel species within the genus Lentilactobacillus, for which the name Lentilactobacillus terminaliae sp. nov. is proposed. The type strain is SPB1-3T (=JCM 35081T=TISTR 10005T).

A novel strain of the genus Holzapfeliella, named He02T, was isolated from flowers of Satureja montana L. in a survey for lactic acid bacteria associated with wild and cultivated plants in the metropolitan area of Valencia, Spain. Partial 16S rRNA gene sequencing revealed a similarity of 99% to Holzapfeliella floricola DSM 23037T=Ryu1-2T. Strain He02T cells are Gram-stain-positive, catalase-negative non-motile rods, usually occurring in pairs. Cells show a pale yellow pigmentation when pelleted. As H. floricola, strain He02T utilized a narrow range of carbohydrates, namely, glucose and fructose, homofermentatively. However, genome sequencing and estimation of average nucleotide identity (ANI) revealed an ANI value of 87.44 with H. floricola DSM 23037T, the only H. floricola strain sequenced to date. A value of 30.5% for digital DNA–DNA hybridization was estimated with the Type Strain Genome Server tool when He02T was compared with strain DSM 23037T. These results indicate that strain He02T constitutes a novel species, for which the name Holzapfeliella saturejae sp. nov. with He02T (=CECT 31001T=DSM 117324T=CCM 9395T) as type strain is proposed.

Six Gram-stain-positive and rod-shaped strains, designated FJAT-51614T, FJAT-51639T, FJAT-52054T, FJAT-52991T, FJAT-53654T and FJAT-53711T, were isolated from a mangrove ecosystem. The condition for growth among the strains varied (pH ranging 5.0–11.0 and temperature 15–45 °C). These strains showed the highest 16S rRNA gene sequence similarity to the genera Bacillus, Metabacillus and Psychrobacillus. Menaquinone MK-7 (100%) was present in all strains except strain FJAT-51614T, which contained MK-7 (32%) and MK-8 (68%). The major fatty acids (>10%) in strains FJAT-52054T and FJAT-51614T were anteiso-C15 : 0 and iso-C14 : 0. The major fatty acid (>10%) in strain FJAT-53654T was anteiso-C15 : 0, while in strain FJAT-51639T were iso-C15 : 0 and iso-C17 : 0. The major fatty acids in strains FJAT-52991T and FJAT-53711T were iso-C15 : 0 and iso-C16 : 0. The major polar lipids in strains FJAT-51639T, FJAT-52991T and FJAT-51614T were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine, while strains FJAT-53711T, FJAT-52054T and FJAT-53654T consist of diphosphatidylglycerol and phosphatidylglycerol. The genome-relatedness values among the present study strains and the closest species were below the recognized cutoff levels for species delineation. The polyphasic analysis comparison results represent six strains as novel species for which the names Bacillus bruguierae sp. nov. (FJAT-51639T=GDMCC 1.3073T=JCM 35615T), Bacillus kandeliae sp. nov. (FJAT-52991T=GDMCC 1.3069T=JCM 35619T), Bacillus yunxiaonensis sp. nov. (FJAT-53711T=GDMCC 1.3068T=JCM 35616T), Metabacillus rhizosphaerae sp. nov. (FJAT-53654T=GDMCC 1.3075T=JCM 35614T), Metabacillus sediminis sp. nov. (FJAT-52054T=GDMCC 1.3074T=JCM 35620T) and Psychrobacillus mangrovi sp. nov. (FJAT-51614T=GDMCC 1.3072T=JCM35478T) are proposed.

Isolates of Leptospira spp. were cultured from water sources at five different sites in central Iowa in the Midwestern United States and characterized by whole-genome sequencing. Isolates were helix-shaped and motile. Genome sequence analyses determined that the isolates could be clearly distinguished from other species described in the genus Leptospira and included one species that belonged to the pathogen subclade P1, one species that belonged to the pathogen subclade P2 and three species that belonged to the saprophyte subclade S1. The names Leptospira gorisiae sp. nov. (type strain WS92.C1T=NVSL-WS92.C1T=KIT0303T), Leptospira cinconiae sp. nov. (type strain WS58.C1T=NVSL-WS58.C1T=KIT0304T), Leptospira mgodei sp. nov. (type strain WS4.C2T=NVSL.WS4.C2T=KIT0305T), Leptospira iowaensis sp. nov. (type strain WS39.C2T=NVSL-WS39.C2T=KIT0306T) and Leptospira milleri sp. nov. (type strain WS60.C2T=NVSL-WS60.C2T=KIT0307T) are proposed.

A bacterial strain, designated as A6T, was isolated from the rhizosphere soil of a healthy muskmelon in Wenchang, Hainan Province, China. The cells of strain A6T were Gram-negative, aerobic, short rod and motile with a single polar flagellum. Strain A6T could tolerate up to 55.0 mM Al3+ and inhibited the growth of Fusarium oxysporum f. sp. melonis, which is the pathogen of muskmelon Fusarium wilt. Growth occurred at 15–37 ℃ (optimum at 30 ℃), pH 4.5–8.0 (optimum pH 6.5) and with 0–3.0 % NaCl (w/v; optimum, 0.5%). Strain A6T shared the highest 16S rRNA gene sequence similarities with Dyella lutea SaT (98.0%), followed by Dyella thiooxydans ATSB10T (98.0%), Frateuria edaphi 5GH9-34T (97.9%), Dyella nitratireducens DHG59T (97.7%), Frateuria defendens DHoT (97.7%) and Frateuria soli 5GH9-11T (97.7%). Phylogenetic trees based on 16S rRNA gene and genomic sequences indicated that strain A6T belonged to the genus Dyella and formed a subclade with Dyella lutea SaT and Dyella thiooxydans ATSB10T. The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA–DNA hybridization (dDDH) values between A6T and its closely related type strains were 78.8–80.8 %, 70.0–71.7 % and 20.5–22.1 %, respectively. The sole respiratory quinone was ubiquinone-8 (Q-8). The polar lipid profile consisted of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), two unidentified aminophospholipids (APL1-2) and three unidentified phospholipids (PL1-3). The major cellular fatty acids (≥5 %) were iso-C17 : 0, C16 : 0, summed feature 9 (iso-C17 : 1  ω9c and/or C16 : 0 10-methyl), iso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. The genome size of strain A6T was 3.7 Mb with a DNA G+C content of 65.1%. Based on the phenotypic, phylogenetic, genotypic and chemotaxonomic features, strain A6T represents a novel species in the genus Dyella, for which Dyella aluminiiresistens A6T sp. nov. is proposed. The type strain is A6T (= GDMCC 1.4640T = KCTC 92542T).

Five pink-pigmented bacterial strains, isolated from human skin and classified within the genus Roseomonas, were examined. Among them, four were identified as Roseomonas mucosa, while strain OT10T was deemed to be a potential novel species. Strain OT10T exhibited characteristics, such as Gram-stain-negative, oxidase positive, motile, strictly aerobic and rod shaped. The cells had multiple flagella at one end, arranged in a lophotrichous pattern. The predominant cellular fatty acids in OT10T were C18:1 ω7c/C18:1 ω6c and C18:1 2OH; ubiquinone (Q)-10 was identified as the sole quinone. Major polar lipids included phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylcholine and two aminolipids. The G+C content of the genome was determined to be 72.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequence similarities revealed that strain OT10T is closely related to Roseomonas gilardii subsp. gilardii ATCC 49956T (97.7%), Roseomonas gilardii subsp. rosea ATCC BAA-691T (97.7%) and R. mucosa ATCC BAA-692T (97.5%). For the comparative genomic analyses, whole-genome sequencing was also conducted for strain OT10T. Considering the chemotaxonomic, genotypic and phenotypic features, as well as the low average nucleotide identity and digital DNA–DNA hybridization values compared to its closest phylogenomic neighbours, OT10T is proposed to be a novel species named Roseomonas cutis sp. nov., with OT10T designated as the type strain (=KCTC 92087T =JCM 34968T).

A novel strain, 681, was isolated from a moss sample taken from the Chrutzelried woods in Canton Zürich, Switzerland. The strain showed potent activity against several fungi and oomycetes. It was affiliated to the Pseudomonas genus by 16S rRNA gene sequence phylogeny. Genome sequencing showed a G+C content of 59.9 mol%. The highest average nucleotide identity was 86.63%, and the highest digital DNA–DNA hybridization value was 32.2% (with Pseudomonas nunensis ln5), considerably below the thresholds for species delineation. Multi-locus phylogeny using 81 concatenated sequences indicated that the strain represented a new species within the Pseudomonas mandelii subgroup. This study details its characterization as a new species. The 681 genome was screened in silico using antiSMASH to reveal candidate secondary metabolite clusters for the strong antifungal activity exhibited by 681. Of the 15 clusters identified, we disrupted the seven best and tested for activity against Fusarium solani. The pyrrolnitrin, rhizoxin, novel PKS-NRPS and acaterin gene clusters contributed significantly to the observed antifungal activity. Phenotypic analyses found that strain 681 cells were aerobic, Gram-negative, motile rods (mean length 2.60 µm and mean width of 0.67 µm) with one to three polar flagella. Optimal growth was at 30 °C, but growth also occurred at 8 °C. The pH range was 6–7, with some growth at pH 8. Robust growth occurred at 0–3% (w/v) NaCl and weak growth at 4% (w/v) NaCl, with the optimum at 1% (w/v) NaCl. Strain 681 was oxidase positive, hydrolysed arginine under anaerobic conditions, showed intense fluorescence on King’s medium B and produced a hypersensitive response in tobacco leaves. Following our investigations, we propose the designation Pseudomonas fungipugnans sp. nov. for this new species. The type strain, 681, is available from the DSMZ and LMG/BCCM culture collections under the designations DSM 115721 and LMG 33039, respectively.

A Gram-stain-negative, aerobic, motile, catalase-positive, oxidase-positive, short rod-shaped marine bacterium, designated as YIC-827T, was isolated from Qingdao, Shandong Province, China. The results showed that cells of strain YIC-827T could grow optimally at 25–35 °C, pH 6.5–7.5 and 2–7% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence showed that the strain YIC-827T was a member of the genus Pseudoalteromonas. The closest relative to this strain was Pseudoalteromonas ruthenica KMM 300T, with a similarity of 98.39%. The digital DNA–DNA hybridization value between the new isolate and phylogenetically related species is 19.6%. Strain YIC-827T could decompose sodium alginate, casein and esters (Tween 20, Tween 40, Tween 60 and Tween 80), but could not hydrolyse starch, cellulose and DNA. The fatty acid profile of a strain consists of a large number of C16:0, C18:1 ω7c and C16:1 ω7c/C16:1 ω6c. The G+C content of the DNA of this strain was determined to be 48.93%. Based on phenotypic characteristics, phylogenetic analysis and DNA–DNA correlation data, the strain YIC-827 T represents a novel species of the genus Pseudoalteromonas with the name Pseudoalteromonas qingdaonensis sp. nov. The type strain of P. qingdaonensis sp. is strain YIC-827T (=MCCC 1K08807T=CGMCC 1.62085T=KCTC 8212T).

Two Gram-stain-negative, motile, non-spore-forming, aerobic or facultative anaerobic and short rod-shaped bacterial strains, 25B02-3T and BH-R2-4, were isolated from surface seawater collected from the Bering Sea and Chukchi Sea, respectively. The 16S rRNA gene sequences of the two strains were identical. The phylogenetic analysis of the 16S rRNA gene sequences indicated that they were related to the genus Tistrella and shared 99.6 and 98.2% sequence similarity with T. bauzanensis BZ78T and T. mobilis IAM 14872T, respectively. Both 16S rRNA gene and genome sequence-based phylogenetic analyses showed that the two strains formed a monophyletic clade within the genus Tistrella, indicating that they may represent a novel species. The digital DNA‒DNA hybridization (dDDH) values and average nucleotide identities (ANI) between the two strains were 93 and 99%, respectively, indicating that they are different strains. The dDDH and ANI values between the two strains and the type strains of the genus Tistrella were 22.4–58.3% and 81.0–95.0%, respectively. These data clearly demonstrated that the two strains represent a separate genomic species of the genus Tistrella. The principal fatty acids were Sum In Feature 8 (C18 : 1 ω7c or C18 : 1 ω6c), C19 : 0 cyclo ω8c, Sum In Feature 2 (C12 : 0 aldehyde or unknown 10.928) and C16 : 0. The predominant respiratory quinone was Q-10, with a minor Q-9. The polar lipids included phosphatidylethanolamine, aminolipids and phospholipids. The genomic DNA G+C contents of strains 25B02-3T and BH-R2-4 were 67.3 mol% and 67.4 mol%, respectively. On the basis of the polyphasic evidence presented in this study, the two strains represent a novel species within the genus Tistrella, for which the name Tistrella arctica sp. nov. is proposed. The type strain is 25B02-3T (=MCCC 1A07333T=KCTC 8340T).

Five aerobic, Gram-stain-negative bacterial strains, designated as C3-2-a3T, B3-2-R+30, C3-2-a4, C3-2-M3 and C3-2-M8, were isolated from the coastal soil of LungmuCo Lake in the Tibet Autonomous Region, PR China. Phylogenetic analyses based on 16S rRNA genes and genomes indicated that these isolates belonged to the genus Luteimonas and showed a high similarity to Luteimonas suaedae LNNU 24178T (99.01%), Luteimonas endophytica RD2P54T (98.80%) and Luteimonas salinisoli SJ-92T (97.67%). The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between strain C3-2-a3T and related reference strains Luteimonas suaedae LNNU 24178T, Luteimonas endophytica RD2P54T and Luteimonas salinisoli SJ-92T were 91.89, 83.11 and 83.86% and 46.90, 26.90 and 28.20%, respectively. All values were below the thresholds for delineating species, supporting their classification as novel species of the genus Luteimonas. The genomic DNA G+C content of strains C3-2-a3T was 68.39%. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and two unidentified phospholipids. The predominant respiratory quinone was ubiquinone-8 (Q-8), aligning with the characteristics of members of the genus Luteimonas. The major fatty acids (>10.0%) of strain C3-2-a3T were identified as iso-C11 :  0, iso-C15 :  0, iso-C16 : 0 and iso-C17 : 1  ω9c. Based on the results of phenotypic, physiological, chemotaxonomic and genotypic characterizations, we propose that the isolates represent a novel species of genus Luteimonas, for which the name Luteimonas salinilitoris sp. nov is proposed. The type strain is C3-2-a3T (=CGMCC 1.14507T=KCTC 8642T).

A polyphasic taxonomic study was carried out on strain T5W1T, isolated from the roots of the aquatic plant Spirodela polyrhiza. This isolate is Gram-negative, rod-shaped, motile, aerobic and non-pigmented. Nearly complete 16S rRNA gene sequence homology related the strain to Pseudomonas, with 98.4% similarity to P. guineae, P. peli and P. leptonychotis. Average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) with the closest phylogenetic neighbour of T5W1T showed differences at the species level, further confirmed by differences in several physiological characteristics. The main fatty acids are summed feature 3 (C16 : 1   ω7c and/or C16 : 1   ω6c), C18 : 1   ω7c, and C16 : 0. The DNA G+C content is 59.3 mol%. Q-9 is the primary ubiquinone found, and phosphatidylethanolamine is the dominant polar lipid, with lesser amounts of phosphatidylglycerol, diphosphatidylglycerol and phosphatidylserine. Based on the results obtained, this bacterium is assigned to the genus Pseudomonas as a new species with the name Pseudomonas spirodelae sp. nov., type strain T5W1T (=NRRL B-65714T =DSM 118085T).

Three aerobic, pink-pigmented, Gram-negative, motile and rod-shaped bacterial strains, designated SD21T, SI9T and SB2T, were isolated from the phyllosphere of healthy litchis collected from three main producing sites of Guangdong Province, PR China. The 16S rRNA gene analysis showed that strains SD21T and SI9T belonged to the genus Methylobacterium (Mtb.) with the highest similarity to Mtb. komagatae DSM 19563T (98.7%) and Mtb. phyllosphaerae CBMB27T (99.8%), respectively, while strain SB2T belonged to the genus Methylorubrum (Mtr.) and showed the highest similarity to Mtr. suomiense DSM 14458T (98.6%). Phylogenomic analysis based on 92 core genes clearly showed that the most closely related type strains of SD21T, SI9T and SB2T were Mtb. komagatae DSM 19563T, Mtb. phyllostachyos ICMP 17619T and Mtr. salsuginis CGMCC 1.6474T, respectively. The ANI and dDDH values between the three isolates and their most closely related type strains were 85.6‒90.1% and 29.5‒40.4%, respectively, much below the threshold values for species delimitation. The isolates showed clear differences from their closely related type strains in terms of growth conditions, enzyme activities, substrates assimilation and contents of the major fatty acids. They all took summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) as the major fatty acid, ubiquinone 10 as the predominant respiratory quinone and phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine as the major polar lipids. The phenotypic, phylogenetic and chemotaxonomic analyses with genome comparison strongly support that the isolates represent three distinct novel species within the genera of Methylobacterium and Methylorubrum, for which the names Methylobacterium litchii sp. nov., Methylobacterium guangdongense sp. nov. and Methylorubrum subtropicum sp. nov. are proposed, with SD21T (=GDMCC 1.4327T=KCTC 8300T), SI9T (=GDMCC 1.4329T=KCTC 8298T) and SB2T (=GDMCC 1.4328T=KCTC 8299T) as the type strains, respectively.

Marine biofilms were newly revealed as a bank of hidden microbial diversity and functional potential. In this study, a Gram-stain-negative, aerobic, oval and non-motile bacterium, designated LMIT008T, was isolated from the biofilm of concrete breakwater structures located in the coastal area of Shantou, PR China. Strain LMIT008T was found to grow at salinities of 1–7% NaCl, at pH 5–8 and at temperatures 10–40 °C. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain LMIT008T belonged to the genus Jannaschia and was closely related to the type strains Jannaschia aquimarina KCTC23555T (96.03%) and Jannaschia marina SHC-163T (95.31%). The draft genome size of the strain LMIT008T was 3.67 Mbp, and the genomic DNA G+C content was 69.83 mol%. The average nucleotide identity value between strain LMIT008T and the closely related type strain J. aquimarina KCTC23555T was 74.82%. The predominant cellular fatty acids were identified as summed feature 8 (C18 : 1  ω7c/C18 : 1  ω6c) and C18 : 0, and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. Ubiquinone-10 (Q-10) is the sole respiratory quinone. Further, genomic analysis of strain LMIT008T showed that the strain harbours abundant genes associated with biofilm formation and environmental adaption, explaining the potential strategies for living on concrete breakwater structures. Based on the morphological, phylogenetic, chemotaxonomic and phenotypic characterization, the strain LMIT008T was considered to represent a novel species in the genus of Jannaschia, for which the name Jannaschia maritima sp. nov. was proposed, with LMIT008T (=MCCC 1K08854T=KCTC 8321T) as the type strain.

A thorough polyphasic taxonomic study, integrating genome-based taxonomic approaches, was carried out to characterize the RB5T strain isolated from root nodules of Retama monosperma growing on the coastal dunes of Bousfer Beach (Oran, Algeria). The 16S rRNA gene sequence analysis revealed that strain RB5T had the highest similarity to Pseudomonas granadensis LMG27940T (98.94%) and Pseudomonas gozinkensis IzPS32dT (98.73%). Phylogenetic studies, including both 16S rRNA gene sequence and multilocus sequence analysis using 16S rRNA, gyrB and rpoD housekeeping genes, positioned RB5T in a distinct branch alongside its closest relative, P. granadensis LMG27940T. Phylogenomic analysis using the Bac120 marker set and Type (Strain) Genome Server confirmed the unique position of RB5T and its close relationship with P. granadensis LMG27940T. Similarly, genomic comparisons using average nucleotide identity based on blast (ANIb) and digital DNA–DNA hybridization (dDDH) revealed values of 92.85 and 59.3%, respectively, when compared with its closest relative, P. granadensis LMG27940T. Both values fall below the established species delimitation thresholds of 95–96% for ANIb and 70% for dDDH, providing strong genomic evidence that strain RB5T represents a novel species. Further average nucleotide identity comparisons with unclassified Pseudomonas spp. (384 genomes) and metagenomic-derived genomes from the Genome Taxonomy Database (GTDB) showed values between 84.27 and 89.2%, indicating that strain RB5T belongs to a unique evolutionary line. The genome of RB5T, with a size of 6 311 310 bp and a G+C content of 60%, harbours several key genes associated with plant growth-promoting traits, making it a promising candidate for sustainable agriculture. Phenotypically, RB5T strain is an aerobic, rod-shaped, Gram-negative, non-spore-forming bacterium that is motile with a single polar flagellum. It grows under a wide range of temperature (4–42 °C) and pH (5–10) conditions and tolerates up to 6% (w/v) NaCl. The main cellular fatty acid composition of RB5T includes C16:0, C17:0 cyclo and the summed features 3 consisting of C16:1 ω7c/C16:1 ω6c. Based on the phylogenetic, phenotypic, chemotaxonomic and genome comparison analyses, strain RB5T was identified as a novel species of the genus Pseudomonas, for which the name Pseudomonas retamae sp. nov. is proposed. The type strain is RB5T (=DSM 117471T=LMG 33633T=CIP 112482T).

A Gram-stain-negative, aerobic and rod-shaped bacterium, designated as HZG-20T, was isolated from a tidal flat in Zhoushan, Zhejiang Province, China. The 16S rRNA sequence similarities between strain HZG-20T and Pikeienuella piscinae RR4-56T, Coraliihabitans acroporae NNCM2T, Parvibaculum indicum P31T and Zhengella mangrovi X9-2-2T were 98.9, 91.7, 91.0 and 91.0%, respectively. Colonies of strain HZG-20T were 1.4 mm in diameter, milky white, round, smooth and convex after cultivating on marine agar at 30 °C for 48 h. Cells were catalase and oxidase-negative. Growth occurred at 15–37 ℃ (optimum, 28 ℃), pH 5.0–9.0 (optimum, pH 6.0–8.0) and with 0–8% (w/v) NaCl (optimum, 1–3%). It contained Menaquinone-8 (H2) as the sole respiratory quinone, and C16:0 (11.8–13.6%), C18:1  ω9c (6.8–13.3%) and C15:0 anteiso (10.9–27.7%) as the major cellular fatty acids. The main polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, one unidentified phospholipid, one unidentified aminolipid, one unidentified phosphoglycolipid, two unidentified glycolipids (GL1–GL2) and three unidentified lipids (L1–L3). The genome of strain HZG-20T was 3 835 886 bp in length, comprised 3746 protein-coding genes, with DNA G+C content of 67.1 mol%. The phylogenetic and phylogenomic trees indicated that strain HZG-20T formed an independent and stable clade with P. piscinae RR4-56T. However, the average nucleotide identity, digit DNA–DNA hybridization and average amino acid identity values between strain HZG-20T and P. piscinae RR4-56T, C. acroporae NNCM2T, P. indicum P31T and Z. mangrovi X9-2-2T were 81.6, 71.1, 68.7 and 69.5%; 23.0, 18.5, 17.9 and 17.5%; and 78.2, 56.8, 56.5 and 61.9%, respectively, together with distinct chemotaxonomic features, indicating strain HZG-20T should not be assigned to known genera. As a result, a novel species of a novel genus within the family Paracoccaceae, designated as Paludibacillus litoralis gen. nov., sp. nov., was proposed. The type strain is HZG-20T (MCCC 1K08468T=KCTC 82692T).

A new alkaliphilic strain of a purple sulphur bacterium designated as Um2 (=KCTC 25734=VKM B-3893=UQM 41073) with bacteriochlorophyll b and internal photosynthetic membranes of tubular type was isolated from the Umhei hydrothermal system (40 °C, pH 9.3 and salinity 0.42 g l−1) located in the Baikal rift zone (Russia). Based on morphological and physiological characteristics, this bacterium was classified as Thioalkalicoccus limnaeus. The 16S rRNA gene sequence similarity of strain Um2 was 96.69% with the type strain of Tac. limnaeus A26T, 95.41% with ‘Thioflavicoccus mobilis’ 8321T and 95.34% with Thiococcus pfennigii 4250. The level of similarity of the ribulose 1,5-bisphosphate carboxylase sequences of strain Um2 and known strains of Thioalkalicoccus showed that they belong to the same species. Comparison of the genome nt sequences of strain Um2 revealed that the new isolate was remote from all other described Chromatiaceae species both in digital DNA–DNA hybridization (21.5%) and in average nt identity (76.7%) at the genus level. However, a genome nt sequence had not been determined for any of the known Thioalkalicoccus strains; therefore, the first genome sequence of a member of the genus Thioalkalicoccus is presented here. Tac. limnaeus Um2 is proposed as the neotype, as strain A26T has been lost from culture collections.

Strain NoAHT (=KACC 23135T=JCM 35999T), a novel Gram-negative, motile bacterium with a rod-shaped morphology, was isolated from the zoo animal faecal samples, specifically the long-tailed goral species Naemorhedus caudatus. The novel bacterial strain grew optimally in a nutrient broth medium under the following conditions: 1–2% (w/v) NaCl, pH 7–8 and 30 °C. The strain NoAHT exhibited high tolerance to NaCl, with the ability to tolerate up to 7% (w/v) NaCl. Based on phylogenetic analyses using 16S rRNA gene sequencing, strain NoAHT was found to have the closest relatedness to Comamonas jiangduensis YW1T (98.5%), Comamonas aquatica ATCC 11330T (97.9%), Comamonas resistens KCTC 82561T (97.9%), Comamonas fluminis CJ34T (97.7%) and Comamonas suwonensis EJ-4T (97.6%). The genome size and genomic DNA G+C content of strain NoAHT were 4.05 Mbp and 55.9 mol%, respectively. A whole-genome-level comparison of strain NoAHT with C. jiangduensis YWT, Comamonas kerstersii LMG 3475T, C. aquatica NBRC 14918T, Comamonas terrigena NBRC 12685T and C. fluminis CJ34T revealed the following orthologous average nucleotide identity values: 80.1, 79.0, 78.6, 76.3 and 75.2%, respectively. The major polar lipids of strain NoAHT were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Considering our findings in chemotaxonomic, genotypic and phenotypic characteristics, strain NoAHT is identified as a novel species within the genus Comamonas, for which the name Comamonas halotolerans sp. nov. is proposed.

A novel yeast species, isolated from the bark of pine trees in Gyeongju, South Korea, and designated as KCTC 37304T (ex-type KACC 410729), is characterized by its genetic, morphological and physiological properties. Molecular phylogenetic analysis involving the D1/D2 domain of the 26S LSU rRNA gene and the internal transcribed spacer (ITS) region confirms that it belongs to the genus Chionosphaera. In comparison to Chionosphaera cuniculicola CBS:10065, the type strain of its closest relative, KCTC 37304T exhibits 8 nucleotide substitutions (~2.07%) in the D1/D2 domain and 54 substitutions (~8.47%) in the ITS region. Morphologically, cells of KCTC 37304T are globose to ovoid, which distinguishes them from the cylindrical cells of C. cuniculicola. Physiologically, KCTC 37304T does not assimilate methanol or ethanol but can utilize succinate and xylitol, further differentiating it from C. cuniculicola. Based on these distinctive genetic, morphological and physiological features, we propose the new species Chionosphaera pinicorticola sp. nov., with KCTC 37304T (ex-type strain KACC 410729) designated as the holotype.