- Volume 73, Issue 12, 2023

Two novel Micromonospora strains, STR1-7T and STR1S-6T, were isolated from the rhizosphere of a Parastrephia quadrangularis plant growing in the Salar de Tara region of the Atacama Desert, Chile. Chemotaxonomic, cultural and phenotypic features confirmed that the isolates belonged to the genus Micromonospora . They grew from 20 to 37 °C, from pH7 to 8 and in the presence of up to 3 %, w/v NaCl. The isolates formed distinct branches in Micromonospora gene trees based on 16S rRNA gene sequences and on a multi-locus sequence analysis of conserved house-keeping genes. A phylogenomic tree generated from the draft genomes of the isolates and their closest phylogenetic neighbours showed that isolate STR1-7T is most closely related to Micromonospora orduensis S2509T, and isolate STR1S-6 T forms a distinct branch that is most closely related to 12 validly named Micromonospora species, including Micromonospora saelicesensis the earliest proposed member of the group. The isolates were separated from one another and from their closest phylogenomic neighbours using a combination of chemotaxonomic, genomic and phenotypic features, and by low average nucleotide index and digital DNA–DNA hybridization values. Consequently, it is proposed that isolates STR1-7T and STR1S-6T be recognized as representing new species in the genus Micromonospora , namely as Micromonospora parastrephiae sp. nov. and Micromonospora tarensis sp. nov.; the type strains are STR1-7T (=CECT 9665T=LMG 30768T) and STR1S-6T (=CECT 9666T=LMG 30770T), respectively. Genome mining showed that the isolates have the capacity to produce novel specialized metabolites, notably antibiotics and compounds that promote plant growth, as well as a broad-range of stress-related genes that provide an insight into how they cope with harsh abiotic conditions that prevail in high-altitude Atacama Desert soils.

Two actinomycete strains, designated MG62T and CRLD-Y-1, were isolated from rhizosphere soil of Koelreuteria paniculata and healthy leaves of Xanthium sibiricum, respectively, in Hunan province, PR China. They could produce abundant aerial mycelia that generated rod-shaped spores with spiny surfaces. Morphological features of the two strains are typical of the genus Streptomyces . Strains MG62T and CRLD-Y-1 exhibited 99.93 % 16S rRNA gene sequence similarity. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between them were 99.99 and 100 %, respectively, suggesting that they belonged to the same species. 16S rRNA gene sequences analysis revealed that the two strains belonged to the genus Streptomyces and showed highest similarities to Streptomyces violarus NBRC 13104T (99.07–99.29 %) and Streptomyces arenae ISP 5293T (99.21–99.35 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains MG62T and CRLD-Y-1 were closely related to S. violarus NBRC 13104T and S. arenae ISP 5293T. However, the ANI, dDDH and multilocus sequence analysis evolutionary distance values between the two strains and their relatives provide a robust basis upon which to verify strains MG62T and CRLD-Y-1 as representing a novel species. Moreover, a comprehensive comparison of phenotypic and chemotaxonomic characteristics further confirmed that the two strains were distinct from their relatives. Based on all these data above, strains MG62T and CRLD-Y-1 should represent a novel Streptomyces species, for which the name Streptomyces koelreuteriae sp. nov. is proposed. The type strain is MG62T (=JCM 34747T=MCCC 1K06175T).

Strains CN4T, CN6, CN7 and CNm7 were isolated from root nodules of Coriaria nepalensis from Murree in Pakistan. They do not form root nodules on C. nepalensis nor on Alnus glutinosa although they deformed root hairs of Alnus. The colonies are bright red-pigmented, the strains form hyphae and sporangia but no N2-fixing vesicles and do not fix nitrogen in vitro. The peptidoglycan of strain CN4T contains meso-diaminopimelic acid; whole cell sugars consist of ribose, mannose, glucose, galactose and rhamnose. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and two unknown lipids represent the major polar lipids; MK-9(H4) and MK-9(H6) are the predominant menaquinones (>15 %), and iso-C16 : 0 and C17 : 1ω8c are the major fatty acids (>15 %). The results of comparative 16S rRNA gene sequence analyses indicated that strain CN4T is most closely related to Frankia saprophytica CN 3T. An MLSA phylogeny using amino acids sequences of AtpD, DnaA, FtsZ, Pgk and RpoB, assigned the strain to cluster 4 non-nodulating species, close to F. saprophytica CN 3T , Frankia asymbiotica M16386T and Frankia inefficax EuI1cT with 0.04 substitutions per site, while that value was 0.075 with other strains. Digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values between CN4T and all species of the genus Frankia with validly published names were below the defined threshold for prokaryotic species demarcation, with dDDH and ANI values at or below 27.8 and 83.7 %, respectively. The four strains CN4T, CN6, CN7 and CNm7 had dDDH (98.6–99.6 %) and ANI values that grouped them as representing a single species. CN4T has a 10.76 Mb genome. CN4T was different from its close phylogenetic neighbours with validly published names in being red-pigmented, in having several lantibiotic-coding clusters, a carbon monoxide dehydrogenase cluster and a clustered regularly interspaced short palindromic repeats (CRISPR) cluster. The results of phenotypic, physiological and phylogenomic analyses confirmed the assignment of strain CN4T (=DSM 114740T = LMG 32595T) to a novel species, with CN4T as type strain, for which the name Frankia nepalensis sp. nov. is proposed.

In this study, a Gram-stain-positive, non-motile, oxidase- and catalase-negative, rod-shaped, bacterial strain (SG_E_30_P1T) that formed light yellow colonies was isolated from a groundwater sample of Sztaravoda spring, Hungary. Based on 16S rRNA phylogenetic and phylogenomic analyses, the strain was found to form a distinct linage within the family Microbacteriaceae . Its closest relatives in terms of near full-length 16S rRNA gene sequences are Salinibacterium hongtaonis MH299814 (97.72 % sequence similarity) and Leifsonia psychrotolerans GQ406810 (97.57 %). The novel strain grows optimally at 20–28 °C, at neutral pH and in the presence of NaCl (1–2 w/v%). Strain SG_E_30_P1T contains MK-7 and B-type peptidoglycan with diaminobutyrate as the diagnostic amino acid. The major cellular fatty acids are anteiso-C15 : 0, iso-C16 : 0 and iso-C14 : 0, and the polar lipid profile is composed of diphosphatidylglycerol and phosphatidylglycerol, as well as an unidentified aminoglycolipid, aminophospholipid and some unidentified phospholipids. The assembled draft genome is a contig with a total length of 2 897 968 bp and a DNA G+C content of 65.5 mol%. Amino acid identity values with it closest relatives with sequenced genomes of <62.54 %, as well as other genome distance results, indicate that this bacterium represents a novel genus within the family Microbacteriaceae . We suggest that SG_E_30_P1T (=DSM 111415T=NCAIM B.02656T) represents the type strain of a novel genus and species for which the name Antiquaquibacter oligotrophicus gen. nov., sp. nov. is proposed.

An anaerobic hyperthermophilic archaeon was isolated from a black smoker chimney with a snail attachment at a water depth of 2 739 m in the Southwest Indian Ocean. The sample was taken from the chimney exterior wall. The enrichment was conducted under a continuous culture with temperature fluctuation of 80–130 °C over 24 h for 42 days at 28 MPa. The isolation was performed at 90 °C at 0.1 MPa. Cells of the isolated strain 813A4T were irregular cocci. Strain 813A4T grew at 60–94 °C (optimal growth at 85 °C) at 0.1 MPa, and growth was detected at up to 99 °C at 28 MPa. At 85 °C, the strain was able to grow at pressures ranging from 0.1 to 110 MPa (optimal pressure, 0.1–40 MPa). At 85 °C, the cells of 813A4T grew at pH 5.5–9 (optimal, pH 7.0) and a NaCl concentration of 1.0–4.0 % (w/v; optimum concentration, 2.5 % NaCl). Strain 813A4T utilized yeast extract, tryptone and peptone as single carbon sources for growth. Elemental sulphur stimulated its growth. The G+C content of the complete genome was 53.48 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 813A4T belonged to the genus Thermococcus , with the highest sequence similarity to Thermococcus barossii SHCK-94T (99.73 %). The average nucleotide identity between strains 813A4T and SHCK-94T was 82.56 %. All these data indicated that strain 813A4T should be classified as representing a novel species of the genus Thermococcus , for which Thermococcus thermotolerans sp. nov. is proposed. The type strain is 813A4T (=JCM 39367T=MCCC M28628T).

A novel Gram-stain-negative, aerobic, non-motile, rod-shaped bacterium, designated pc2-12T, was isolated from the rhizosphere soil of the herb Pyrola calliantha collected from arid areas of Tibet. The strain grew most vigorously with 1 % (w/v) NaCl, at pH 7.0 and at 25 °C. According to the results of 16S rRNA gene sequence analysis, pc2-12T was closely related to the members of the genus Chryseobacterium , with highest levels of sequence similarity to Chryseobacterium viscerum 687B-08T (98.42 %), Chryseobacterium oncorhynchi 701B-08T (98.11 %) and Chryseobacterium ureilyticum DSM 18017T (97.98 %). The average nucleotide identity values between pc2-12T and C. viscerum 687B-08T, C. oncorhynchi 701B-08T and C. ureilyticum DSM 18017T were 79.71, 79.49 and 79.26 %, respectively. The in silico DNA–DNA hybridisation values between pc2-12T and C . viscerum 687B-08T, C. oncorhynchi 701B-08T and C. ureilyticum DSM 18017T were 23.30, 23.00 and 22.90 %, respectively. The draft genome sequence of pc2-12T was 4.64 Mb long, with DNA G+C content of 37.0 mol%. The fatty acids contained in the cells of pc2-12T were mainly composed of iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c). The main polar lipid was phosphatidylethanolamine. MK-6 was the sole respiratory quinone. On the basis of the results of analysis of all the data described, pc2-12T is considered to represent a novel species of the genus Chryseobacterium , for which the name Chryseobacterium pyrolae sp. nov., is proposed. The type strain is pc2-12T (=GDMCC 1.3256T= JCM 35712T).

A novel yellow-pigmented bacterial strain, designated YZ-48T, was isolated from the sediment of the Yangtze River, PR China. Cells were Gram-stain-negative, non-motile, rod-shaped, strictly aerobic, catalase-positive and oxidase-positive. The strain grew optimally on R2A medium at 37 °C, pH 7.0 and with 1.0 % (w/v) NaCl. Strain YZ-48T showed the closest 16S rRNA gene sequence similarity to Flavobacterium solisilvae SE-s27T (96.4 %) and F. dankookense DSM 25687T (96.2 %). The phylogenetic trees based on 16S rRNA gene sequences showed that strain YZ-48T belonged to the genus Flavobacterium but formed a distinct phylogenetic lineage. The obtained average nucleotide identity and digital DNA–DNA hybridization values between YZ-48T and the two closest strains were 75.0 and 74.5 % and 19.6 and 19.0 %, respectively. The sole respiratory quinone was MK-6. The major polar lipids were phosphatidylethanolamine, two unidentified aminolipids and three unidentified polar lipids. The major cellular fatty acids were iso-C16 : 0, iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3-OH, iso-C15 : 0 3-OH and iso-C16 : 0 3-OH. The DNA G+C content was 40.2 mol%. Based on the phenotypic, chemotaxonomic, phylogenetic and genomic data, strain YZ-48T represents a novel species of the genus Flavobacterium , for which the name Flavobacterium sedimenticola sp. nov. is proposed, with strain YZ-48T (=KCTC 82329T=CCTC AB 2023061T=MCCC 1K08804T) as the type strain.

A novel Gram-stain-negative strain, designated S37H4T, was isolated from an intertidal surface sediment sample collected from Zhanjiang City, Guangdong province, south PR China. Cells of the strain were aerobic, non-flagellated, long rod-shaped and motile by gliding. S37H4T could grow at 4–40 °C, pH 7.0–8.5 and in 2.0–15.0 % NaCl, with optimal growth at 25–30 °C, pH 7.5 and 9.0 % NaCl, respectively. S37H4T was capable of nitrite removal under high-salt conditions, and there were three denitrification genes, nirK, norB and nosZ, in its genome. The results of phylogenetic analyses based on the 16S rRNA gene and genome sequences indicated that S37H4T represented a member of the genus Marivirga and formed a subclade with Marivirga lumbricoides JLT2000T. S37H4T showed the highest 16S rRNA sequence similarity to M. lumbricoides JLT2000T (98.3 %) and less than 97.0 % similarity with other type strains of species of the genus Marivirga . The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between S37H4T and the reference type strains of species of the genus Marivirga were 70.7–74.3 % and 18.2–19.2 %, respectively. The major fatty acids of S37H4T were iso-C15 : 0, iso-C15 : 1G, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c). The major respiratory quinone of this novel strain was MK-7, and the predominant polar lipids were identified as phosphatidylethanolamine, an unidentified aminolipid, an unidentified phospholipid and three unidentified lipids. The results of analyses of phylogenetic, genomic, physiological and biochemical characteristics indicated that S37H4T represented a novel species of the genus Marivirga , for which the name Marivirga aurantiaca sp. nov. is proposed. The type strain is S37H4T (= GDMCC 1.1866T = KACC 21922T).

A bacterium, designated strain ZK17L-C2T, was isolated from the leaf tissues of wheat (Triticum aestivum) collected in Chengdu, Sichuan Province, PR China. It is aerobic, non-motile, Gram-negative, rod-shaped and red-to-pink in colour. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZK17L-C2T belonged to the genus Hymenobacter and was most closely related to Hymenobacter rigui KCTC 12533T (98.68 %) and Hymenobacter metallilatus 9PBR-2T (98.19 %). Digital DNA–DNA hybridization (dDDH) values between strain ZK17L-C2T and these two type strains were 26.6 and 26.5 %, and average nucleotide identity (ANI) values were 84.9 and 84.8 %, respectively; these values are lower than the proposed and generally accepted species boundaries for dDDH and ANI. The genomic DNA G+C content of strain ZK17L-C2T was 59.4 mol%. It can grow at pH 5.5–7.5 and 15–30 °C, which is different from the closely related type strains. The major fatty acids of strain ZK17L-C2T were iso-C15 : 0, C16 : 0 and C18 : 0. Overall, the results from biochemical, chemical taxonomy and phylogenetic analyses indicate that strain ZK17L-C2T (=CGMCC 1.19373T=KCTC 92184 T) represents a new species of the genus Hymenobacter , for which the name Hymenobacter endophyticus sp. nov. is proposed.

An orange-coloured bacterium, designated as strain GRR-S3-23T, was isolated from a tidal flat sediment collected from Garorim Bay, Chuncheongbuk-do, Republic of Korea. Cells of GRR-S3-23T were aerobic, Gram-stain-negative, rod-shaped and motile. GRR-S3-23T grew at 18–40 °C (optimum, 30 °C), pH 7.0–9.0 (optimum, pH 7.0) and with 2–4 % NaCl (optimum, 2–3 % w/v). Results of 16S rRNA gene sequence analysis indicated that GRR-S3-23T was closely related to Tenacibaculum aiptasiae a4T (97.6 %), followed by Tenacibaculum aestuarii SMK-4T (97.5 %), Tenacibaculum mesophilum MBIC 1140T (97.4 %), Tenacibaculum singaporense TLL-A2T (97.3 %), Tenacibaculum crassostreae JO-1T (97.2 %),and Tenacibaculum sediminilitoris YKTF-3T (97.1 %). The average amino acid identity values between GRR-S3-23T and the related strains were 86.8–72.8 %, the average nucleotide identity values were 83.3–74.1 %, and the digital DNA–DNA hybridization values were 27.0–19.6 %. GRR-S3-23T possessed menaquinone-6 (MK-6) as major respiratory quinone and had summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c, 20.6 %) and iso-C15 : 1G (10.8 %) as major fatty acids (>10.0 %). The polar lipid profiles of GRR-S3-23T contained phosphatidylethanolamine, one unidentified aminolipid, one unidentified aminophospholipid, three unidentified lipids, one unidentified glycolipid and four unidentified phospholipids. The DNA G+C content of GRR-S3-23T was 33.7%. On the basis of the results of the polyphasic analysis involving phylogenetic, phylogenomic, physiological and chemotaxonomic analyses described in this study, GRR-S3-23T is considered to represent a novel species within the genus Tenacibaculum , for which the name Tenacibaculum tangerinum is proposed. The type strain is GRR-S3-23T (=KCTC 102029T=KACC 23271T=JCM 36353T).

A Gram-stain-positive, rod-shaped, facultatively anaerobic and homofermentative strain, named WILCCON 0030T, was isolated from sauerkraut (fermented cabbage) collected from a local market in the Moscow region of Russia. Comparative analyses based on 16S rRNA gene sequence similarity and whole genome relatedness indicated that strain WILCCON 0030T was most closely related to the type strains Lactiplantibacillus nangangensis NCIMB 15186T, Lactiplantibacillus daoliensis LMG 31171T and Lactiplantibacillus pingfangensis LMG 31176T. However, the average nucleotide identity and digital DNA–DNA hybridization prediction values with these closest relatives only ranged from 84.6 to 84.9 % and from 24.1 to 24.7 %, respectively, and were below the 95.0 and 70.0% thresholds for species delineation. Substantiated by further physiological and biochemical analyses, strain WILCCON 0030T represents a novel species within the genus Lactiplantibacillus for which we propose the name Lactiplantibacillus brownii sp. nov. (type strain WILCCON 0030T=DSM 116485T=LMG 33211T).

An aerobic, Gram-stain-positive, rod-shaped, endospore-forming bacterial strain, designated BB3-R1T, was isolated from cow faeces sampled in Daejeon, Republic of Korea. Growth was observed at 25–45 °C (optimum, 35–40 °C) and pH 7.0–9.0 (optimum, pH 8.0), with up to 3 % (w/v) NaCl (optimum, 0 % NaCl). blast analysis of 16S rRNA gene sequences revealed the highest sequence similarity of strain BB3-R1T to Brevibacillus borstelensis NRRL NRS-818T (98.8 %) followed by Brevibacillus panacihumi JCM 15085T (97.5 %). According to 16S rRNA gene and whole-genome based phylogenetic trees, strain BB3-R1T clustered with Brevibacillus composti FJAT-54423T and B. borstelensis NRRL NRS-818T. OrthoANI and dDDH values of strain BB3-R1T with the closely related strains were lower than 77.5 and 26.8 %, respectively. The major menaquinones and polar lipids of the strain were MK-7 and phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine, respectively. The major fatty acids (>10 %) were C14 : 0 iso, C15 : 0 iso, C15 : 0 anteiso and C16 : 1  ω7c alcohol. The cell-wall peptidoglycan contained cross-linked meso-diaminopimelic acid (type A1 gamma). The phenotypic, chemotaxonomic and genotypic data obtained in this study showed that the strain represents a novel species of the genus Brevibacillus , for which the name Brevibacillus ruminantium sp. nov. (type strain BB3-R1T=KACC 22663T=NBRC 115962T) is proposed.

Two Gram-stain-negative, rod-shaped, non-spore-forming, strictly aerobic, motile bacteria with a single polar flagellum, designated strains C1424T and C2222T, were isolated from marine alga collected from the sea shore at Yantai, PR China. Strain C1424T grew at 4–37 °C and in the presence of 1–9 % (w/v) NaCl, while strain C2222T grew at 4–32 °C with 1–6 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences and concatenated amino acid sequences of 120 ubiquitous single-copy proteins showed that both strains C1424T and C2222T belonged to the genus Marinomonas , showing highest 16S rRNA gene sequence similarities to the type strains of Marinomonas primoryensis (98.1 %) and Marinomonas dokdonensis (98.1 %), respectively. The major fatty acids of the two strains were C18 : 1  ω6c and/or C18 : 1  ω7c, C16 : 1  ω6c and/or C16 : 1  ω7c and C16 : 0, their predominant polar lipids were phosphatidylethanolamine and phosphatidylglycerol, and their sole respiratory quinone was Q8. On the basis of polyphasic analyses, strains C1424T and C2222T are considered to represent two novel species within the genus Marinomonas , for which the names Marinomonas transparens sp. nov. and Marinomonas sargassi sp. nov. are proposed. The type strains are C1424T (=KCTC 72119T=MCCC 1K03601T) and C2222T (=KCTC 72120T=MCCC 1K03602T), respectively.

A novel bacterial strain, GSTT-20T was isolated from an infected, prosthetic endovascular graft explanted from a shepherd in London, United Kingdom. This strain was an aerobic, catalase-positive, oxidase-negative, Gram-stain-negative, motile, curved rod. It grew on blood agar, chocolate agar and MacConkey agar incubated at 37 °C in an aerobic environment after 48 h, appearing as yellow, mucoid colonies. Analysis of the complete 16S rRNA gene sequence showed closest similarity to Variovorax paradoxus with 99.6 % identity and Variovorax boronicumulans with 99.5 % identity. Phylogenetic analysis of the 16S rRNA gene sequence and phylogenomic analysis of single nucleotide polymorphisms within 1530 core genes showed GSTT-20T forms a distinct lineage in the genus Variovorax of the family Comamonadaceae . In silico DNA–DNA hybridization assays against GSTT-20T were estimated at 32.1 % for V. boronicumulans and 31.9 % for V. paradoxus . Genome similarity based on average nucleotide identity was 87.50 % when comparing GSTT-20T to V. paradoxus . Based on these results, the strain represented a novel species for which the name Variovorax durovernensis sp. nov. was proposed. The type strain is GSTT-20T (NCTC 14621T=CECT 30390T).

Two novel Pseudomonas strains, SA3-5T and SA3-6, were isolated from a tidal flat (getbol) in the Republic of Korea. Strains SA3-5T and SA3-6 were subjected to polyphasic characterization to determine their taxonomic affiliations. Cells were Gram-stain-negative, aerobic, rod-shaped and motile by using peritrichous flagella. Based on their 16S rRNA gene sequences, strains SA3-5T and SA3-6 exhibited a high degree of similarity (100 %) and were classified within the genus Pseudomonas . Furthermore, the closest related species to SA3-5T and SA3-6 were Pseudomonas taeanensis MS-3T (98.3 %). The ranges of average nucleotide identity and digital DNA–DNA hybridization values between SA3-5T and closely related species were 75.9–89.1% and 21.3–38.7%, respectively, both of which being below the thresholds for delineating novel strains. Strain SA3-5T and SA3-6 contained C16 : 1 ω6с and/or C16 : 1 ω7с (summed feature 3), C16 : 0 and C18 : 1 ω6с and/or C18 : 1 ω7с (summed feature 8) as the major fatty acids. The predominant respiratory quinone was Q-9. The DNA G+C content of strain SA3-5T was 62.5 mol%. Based on their combined phenotypic, chemotaxonomic and phylogenetic characterisitics, strains SA3-5T and SA3-6 represent a novel species of the genus Pseudomonas for which the name Pseudomonas aestuarii sp. nov. is proposed. The type strain is SA3-5T (=KCTC 92395T=JCM 35697T).

Two Gram-stain-negative, chemoheterotrophic, aerobic bacteria, designated IC7T and JM2-8T, were isolated from seawater of the Yellow Sea of China and rhizosphere soil of mangroves in Xiamen, Fujian, respectively. Phylogenetic analyses based on 16S rRNA gene and genome sequences showed that these two novel strains belonged to the family Roseobacteraceae . Strain IC7T formed a coherent lineage within the genus Pseudodonghicola , showing 98.05 % 16S rRNA gene sequence similarity to Pseudodonghicola xiamenensis Y-2T. Strain JM2-8T was most closely related to members of the genus Sedimentitalea , showing 96.51 and 96.73 % 16S rRNA gene sequence similarities to Sedimentitalea nanhaiensis NH52FT and Sedimentitalea todarodis KHS03T, respectively. The two novel strains contained Q-10 as the major quinone, and phosphatidylethanolamine, aminophospholipid, phosphatidylglycerol and phosphatidylcholine as the principal polar lipids. The main fatty acid of strain IC7T was C19 : 0 cyclo ω8c, while the fatty acid profile JM2-8T was dominated by summed feature 8 containing C18 : 1  ω7c and/or C18 : 1  ω6c. The average nucleotide identity and digital DNA–DNA hybridization values between these two novel isolates and their closely related species were below the cut-off values of 95–96 and 70 %, respectively. The combined genotypic and phenotypic data show that strain IC7T represents a novel species of the genus Pseudodonghicola , for which the name Pseudodonghicola flavimaris sp. nov. is proposed, with the type strain IC7T (=MCCC 1A02763T=KCTC 82844T), and strain JM2-8T represents a novel species of the genus Sedimentitalea , for which the name Sedimentitalea xiamensis sp. nov. is proposed, with the type strain JM2-8T (=MCCC 1A17756T=KCTC 82846T).

A Gram-stain-negative, aerobic, non-flagellated and coccoid or ovoid bacterial strain, BSSL-BM11T, was isolated from sand of coastal dunes along the Yellow Sea of the Korean peninsula. Strain BSSL-BM11T grew optimally at 30 °C, at pH 7.0–8.0 and in the presence of 2.0–3.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences, the up-to-date bacterial core gene set and average amino acid identity (AAI) showed that strain BSSL-BM11T forms a cluster with the type strains of Tianweitania sediminis and Corticibacterium populi . Strain BSSL-BM11T showed 16S rRNA gene sequence similarities of 98.3 and 98.0 % to the type strains of T. sediminis and C. populi , respectively, and less than 96.4 % to the type strains of the other recognized species. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between strain BSSL-BM11T and the type strains of T. sediminis and C. populi were 77.0–84.8 % and 20.0–28.1 %, respectively. The 16S rRNA gene similarity, AAI, ANI and dDDH values between T. sediminis Z8T and C. populi KCTC 42249T were 98.0, 77.4, 76.7 and 20.1 %, respectively. The DNA G+C content of strain BSSL-BM11T from genomic sequence data was 61.3 mol%. Strain BSSL-BM11T contained Q-10 as the predominant ubiquinone and C18 : 1  ω7c, C16 : 0 and cyclo C19 : 0  ω8c as the major fatty acids. The major polar lipids of strain BSSL-BM11T were phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. Based on the polyphasic data, it is proposed that C, populi be reclassified as a member of the genus Tianweitania . Phenotypic and phylogenetic analyses revealed that strain BSSL-BM11T is separated from T. sediminis and C. populi . On the basis of the data presented here, strain BSSL-BM11T (=KACC 21634T=NBRC 114503T) is considered to represent a novel species of the genus Tianweitania , for which the name Tianweitania aestuarii sp. nov. is proposed.

During a large-scale bacterial culturing effort of biofilms in the vicinity of a rainbow trout aquaculture facility in Idaho, USA, 10 isolates were identified as having pathogen-inhibiting activity and were characterized further. These isolates were shown to be Gram-negative, rod-shaped bacteria belonging to the genus Pseudomonas . Whole-genome comparisons and multi-locus sequence analysis using four housekeeping genes (16S rRNA, gyrA, rpoB and rpoD) showed that these 10 isolates clustered into four distinct species groups. These comparisons also indicated that these isolates were below the established species cutoffs for the genus Pseudomonas . Further phenotypic characterization using API 20NE, API ZYM and Biolog GENIII assays and chemotaxonomic analysis of cellular fatty acids were carried out. Based on the genomic, physiological and chemotaxonomic properties of these isolates, we concluded that these strains composed four novel species of the genus Pseudomonas . The proposed names are as follows: Pseudomonas aphyarum sp. nov. consisting of strains ID233, ID386T and ID387 with ID386T (=DSM 114641T=ATCC TSD-305T) as the type strain; Pseudomonas rubra sp. nov. consisting of strains ID291T, ID609 and ID1025 with ID291T (=DSM 114640T=ATCC TSD-303T) as the type strain; Pseudomonas idahonensis sp. nov. consisting of strains ID357T and ID1048 with ID357T (=DSM 114609T=ATCC TSD-304T) as the type strain; and Pseudomonas fontis sp. nov. consisting of strains ID656T and ID681 with ID656T (=DSM 114610T=ATCC TSD-306T) as the type strain.

A sulphur-oxidizing and nitrogen-fixing bacterium, designated strain LS2T, was isolated from freshwater collected from the Pearl River in Guangzhou, PR China. The strain was an obligate chemolithoautotroph, utilizing reduced sulphur compounds (sulphide, sulphite, elemental sulphur, thiosulphate and tetrathionate) as energy sources and electron donors. Diazotrophic growth of strain LS2T was observed at 15–40 °C, pH 5–9, with a NaCl concentration range of 0–0.68 mol l−1 and with oxygen content higher than 21 %. The major cellular fatty acids were summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c) and C16 : 0. The DNA G+C content of the complete genome sequence was 60.7 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain LS2T formed a lineage within the family Halothiobacillaceae , showing gene sequence identity of 96.8 % with its closest relative Halothiobacillus neapolitanus c2. The genome of strain LS2T contains multiple genes encoding sulphur-oxidizing enzymes that catalyse the oxidation of reduced sulphur compounds and an nif complex encoding enzymes for nitrogen fixation. In addition, the genome contains genes encoding cbb3 -type cytochrome c oxidase, aa3 -type cytochrome c oxidase, bd-type quinol oxidase and cytochrome o oxidase, which enable the survival strain LS2T under oxic and microaerophilic conditions. On the basis of phenotypic, genotypic and phylogenetic data, strain LS2T is considered to represent a novel species of the genus Halothiobacillus , for which the name Halothiobacillus diazotrophicus sp. nov. is proposed. The type strain is LS2T (=GDMCC 1.4095T=JCM 39442T).