- Volume 70, Issue 9, 2020

Strain SDU3-2T was isolated from a soil sample collected in Shandong Province, PR China. Cells of SDU3-2T were spherical, Gram-stain-positive, aerobic and non-motile. Cellular growth of the strain occurred at 25–45 °C, pH 5.5–8.5 and with 0–1.5 % (w/v) of NaCl. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain SDU3-2T was closest to the type strain Deinococcus murrayi ALT-1bT with a similarity of 95.2 %. The draft genome was 3.49 Mbp long with 69.2 mol% G+C content. Strain SDU3-2T exhibited high resistance to gamma radiation (D10 >12 kGy) and UV (D10 >900 J m−2). The strain encoded many genes for resistance to radiation and oxidative stress, which were highly conserved with other Deinococcus species, but possessed interspecific properties. The major fatty acids of SDU3-2T cells were C15 : 1  ω6c, C16 : 1  ω7c/C16 : 1  ω6c, and C17 : 1  ω8c, the major menaquinone was menaquinone-8, and the major polar lipids were an unidentified phosphoglycolipid, four unidentified glycolipids and an unidentified phospholipid. The average nucleotide identity and DNA–DNA hybridization results further indicated that strain SDU3-2T represents a new species in the genus Deinococcus , for which the name Deinococcus terrestris sp. nov. is proposed. The type strain is SDU3-2T (=CGMCC 1.17147T=KCTC 43098T).

Kiritimatiellaeota is widespread and ecologically important in various anoxic environments. However, the portion of culturable bacteria within this phylum is quite low and, in fact, there is only one currently described species. In this study, a novel anaerobic, non-motile, coccoid, Gram-stain-negative bacterial strain, designated S-5007T, was isolated from surface marine sediment. The 16S rRNA gene sequence was found to have very low 16S rRNA gene sequence similarity to the nearest known type strain, Kiritimatiella glycovorans L21-Fru-ABT (84.9 %). The taxonomic position of the novel isolate was investigated using a polyphasic approach and comparative genomic analysis. Phylogenetic analyses based on 16S rRNA genes and genomes indicated that strain S-5007T branched within the radiation of the phylum Kiritimatiellaeota . Different from the type strain, strain S-5007T can grow under microaerobic conditions, and the genomes of strain S-5007T and the other strains in its branch have many more antioxidant-related genes. Meanwhile, other different metabolic features deduced from genome analysis supported the separate evolution of the proposed class (strain S-5007T branch) and K. glycovorans L21-Fru-ABT. Based on phylogenetic and phenotypic characterization studies, Tichowtungia aerotolerans gen. nov., sp. nov. is proposed with S-5007T (=MCCC 1H00402T=KCTC 15876T) as the type strain, as the first representative of novel taxa, Tichowtungiales ord. nov., Tichowtungiaceae fam. nov. in Tichowtungiia class. nov.

A novel bacterium, designated strain KXZD1103T, was isolated from sediment collected at a cold seep field of the Formosa Ridge in the South China Sea. Cells were Gram-stain-negative, facultatively anaerobic, motile, oxidase- and catalase-positive, and grew optimally at 28 °C, pH 6.0–pH 7.0 and in the presence of 1–3 % (w/v) NaCl. The major cellular fatty acids were summed feature 8 (C18 : 1  ω7c/C18 : 1  ω6c), summed feature 3 (C16 : 1  ω7c/C16 : 1  ω6c) and C16 : 0. The major respiratory ubiquinone was Q-8. The predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. Analysis of 16S rRNA gene sequences revealed that strain KXZD1103T grouped with members of the genus Nitrincola , with Nitrincola lacisaponensis 4CAT (98.1 % sequence similarity) and Nitrincola schmidtii R4-8T (97.7 %) as its closest neighbours. Genome sequencing revealed a genome size of 4.17 Mb and a DNA G+C content of 50.1 %. Genomic average nucleotide identity values for strain KXZD1103T with the type strains within the genus Nitrincola ranged from 71.0 to 75.7 %, while the in silico DNA–DNA hybridization values for strain KXZD1103T with these strains ranged from 16.1 to 21.6 %. On the basis of the results of phylogenetic, phenotypic and chemotaxonomic analyses, strain KXZD1103T is considered to represent a novel species of the genus Nitrincola , for which the name Nitrincola iocasae sp. nov. is proposed. The type strain is KXZD1103T (=KCTC 72678T=MCCC 1K04283T).

A Gram-stain-negative, facultative anaerobic, motile, short rods and yellow-pigmented bacterium, designated strain THG-DN7.12T, was isolated from water collected at Jungwon waterfall on Yongmun mountain, Republic of Korea. According to 16S rRNA gene sequence comparisons, strain THG-DN7.12T was found to be most closely related to Aquitalea denitrificans 5YN1-3T (98.9 % sequence similarity), Aquitalea magnusonii TRO-001DR8T (98.7 %) and Aquitalea pelogenes P1297T (98.0 %). The DNA–DNA relatedness between strain THG-DN7.12T and its phylogenetically closest neighbours was below 70.0 %. The strain's DNA G+C content was 59.7 mol%. The major polar lipid was found to be phosphatidylethanolamine. Summed feature 3 (C16 : 1  ω7c and/or C16 : 1  ω6c) and C16 : 0 were identified as the major fatty acids. Ubiquinone Q-8 was detected as the only respiratory quinone. These data supported the affiliation of strain THG-DN7.12T to the genus Aquitalea . Strain THG-DN7.12T was distinguished from related Aquitalea species by physiological and biochemical tests. Therefore, the novel isolate represents a novel species, for which the name Aquitalea aquatilis sp. nov. is proposed, with THG-DN7.12T as the type strain (=KACC 18847T=CCTCC AB 2016185T).

An obligate aerobic and bacteriochlorophyll a-containing bacterium, designated strain AI77T, was isolated from a fish farm in Uwa Sea, Japan. Cells were Gram-stain-negative, coccoid- to oval-shaped, and showed no motility. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain AI77T is a member of the genus Roseobacter and closely related to Roseobacter ponti MM-7T (97.8 %), Roseobacter denitrificans OCh 114T (97.3 %) and Roseobacter litoralis OCh 149T (97.3 %). The G+C content of strain AI77T was 61.0 mol%. The average amino acid identity values of the genome in strain AI77T with those in R. denitrificans OCh 114T and R. litoralis OCh 149T were 73.26 % (SD 16.46) and 72.63 % (SD 16.76), respectively. The digital DNA–DNA hybridization values of strain AI77T with the type strains R. denitrificans OCh 114T and R. litoralis OCh 149T were 18.70 and 18.50 %, respectively. The dominant fatty acids (>10 % of total fatty acids) of AI77T were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and saturated fatty acid C16 : 0. The sole respiratory quinone was ubiquinone-10. The predominant polar lipids were phosphatidylcholine, phosphatidylglycerol and diphosphatidylglycerol. Based on the genetic and phenotypic data obtained herein, we conclude that strain AI77T represents a new species of the genus Roseobacter , for which we propose the name Roseobacter cerasinus sp. nov.; the type strain is AI77T (=DSM 110091T=NBRC 114115T).

Two Gram-stain-negative, Fe(III)-reducing, facultatively anaerobic, motile via a single polar flagellum, rod-shaped bacterial strains, designated IMCC35001T and IMCC35002T, were isolated from tidal flat sediment and seawater, respectively. Results of 16S rRNA gene sequence analysis showed that IMCC35001T and IMCC35002T shared 96.6 % sequence similarity and were most closely related to Ferrimonas futtsuensis FUT3661T (98.6 %) and Ferrimonas kyonanensis Asr22-7T (96.8 %), respectively. Draft genome sequences of IMCC35001T and IMCC35002T revealed 4.0 and 4.8 Mbp of genome size with 61.0 and 51.8 mol% of DNA G+C content, respectively. Average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between the two strains were 73.1 and 19.8 %, respectively, indicating that they are separate species. The two genomes showed ≤84.4 % ANI and ≤27.8 % dDDH to other species of the genus Ferrimonas , suggesting that the two strains each represent novel species. The two strains contained both menaquinone (MK-7) and ubiquinones (Q-7 and Q-8). Major fatty acids of strain IMCC35001T were iso-C15 : 0, C18 : 1  ω9c, C17 : 1  ω8c and C16 : 0 and those of strain IMCC35002 T were C18 : 1  ω9c, C16 : 0 and summed feature 3 (C16 : 1  ω7c and/or C16 : 1  ω6c). Major polar lipids in both strains were phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipid, unidentified aminophospholipid and unidentified lipids. The two strains reduced Fe(III) citrate, Fe(III) oxyhydroxide, Mn(IV) oxide and sodium selenate but did not reduce sodium sulfate. They were also differentiated by several phenotypic characteristics. Based on the polyphasic taxonomic data, IMCC35001T and IMCC35002T were considered to represent each novel species in the genus Ferrimonas , for which the names Ferrimonas sediminicola sp. nov. (IMCC35001T=KACC 21161T=NBRC 113699T) and Ferrimonas aestuarii (IMCC35002T=KACC 21162T=NBRC 113700T) sp. nov. are proposed.

A novel bacterial strain, designated TBM-1T, isolated from a freshwater lake in Taiwan, was characterized using a polyphasic taxonomic approach. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain TBM-1T formed a phylogenetic lineage in the genus Ideonella . Analysis of 16S rRNA gene sequences showed that strain TBM-1T was most closely related to Ideonella dechloratans CCUG 30898T with 98.4 % sequence similarity. The average nucleotide identity, average amino acid identity and digital DNA–DNA hybridization values between strain TBM-1T and closely related strains of the genus Ideonella were 74.4–77.5 %, 69.7–75.4 % and 19.8–21.8 %, respectively, supporting that strain TBM-1T represents a novel species of the genus Ideonella . Cells were Gram-stain-negative, motile by means of a single polar flagellum, rod-shaped and formed blue colonies. Optimal growth occurred at 30 °C, pH 6 and 0 % NaCl. The predominant fatty acids of strain TBM-1T were summed feature 3 (C16 : 1   ω7c and/or C16 : 1   ω6c), C18 : 1  ω7c and C16 : 0. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, two uncharacterized aminophospholipids and two uncharacterized phospholipids. The main polyamine was putrescine. The major isoprenoid quinone was Q-8. The estimated genome size was 5.26 Mb, with an average G+C content of 70.0 mol%. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain TBM-1T should be classified in a novel species of the genus Ideonella , for which the name Ideonella livida sp. nov. is proposed. The type strain is TBM-1T (=BCRC 81199T =LMG 31339T).

A bacterial strain, BIT-B35T, was isolated from the gut of plastic-eating larvae of the Coleoptera insect Zophobas atratus. Its taxonomic position was determined by using a polyphasic approach. Cells were white-pigmented, Gram-stain-negative, motile short rods with terminal flagella. The 16S rRNA gene sequence (1411 bp) of strain BIT-B35T showed highest similarity (98.1%) to Escherichia fergusonii ATCC 35469T and Citrobacter koseri LMG 5519T. The results of phylogenetic analyses, based on the 16S rRNA gene, concatenated sequences of seven housekeeping genes (atpD, gyrB, infB, rpoB, pyrG, fusA and leuS) and genome sequences, placed strain BIT-B35T in a separate lineage among the family of Enterobacteriaceae . The major fatty acids were C16 : 0, C17 : 0 cyclo and C19 : 0 cyclo ω8c. The genomic DNA G+C content of strain BIT-B35T was 57.1 mol%. The chemotaxonomic data plus results of physiological and biochemical tests also distinguished strain BIT-B35T from members of other genera within the family Enterobacteriaceae . Therefore, strain BIT-B35T is considered to represent a novel species of a novel genus within the family Enterobacteriaceae , for which the name Intestinirhabdus alba gen. nov., sp. nov. is proposed. The type strain is BIT-B35T (=CGMCC 1.17042T=KCTC 72448T).

A Gram-stain-negative, motile, aerobic and heterotrophic bacterium, designated as GYS_M3HT, was isolated from marine coastal sediment sampled at Xiamen Island. Cells were rod-shaped with one polar flagellum and weakly positive for oxidase and catalase. Growth of the strain occurred at pH 6–9 (optimum, pH 7–8), at 15–37 °C (optimum, 28 °C) and with NaCl concentrations of 1.0–6.0 % (optimum, 2.0 %). It had highest 16S rRNA similarity (97.7 %) to Ketobacter alkanivorans GI5T, followed by the members of the genus Alcanivorax (lower than 91.2 %). The results of phylogenetic analysis indicated that it belonged to the genus Ketobacter within the family Alcanivoracaceae . In addition, the average nucleotide identity and digital DNA–DNA hybridization values between strain GYS_M3HT and K. alkanivorans GI5T were 71.4 and 19.7 %, respectively, indicating that strain GYS_M3HT belonged to a novel species. Its genome consisted of 5 318 758 bp, with a genomic DNA G+C content of 50.0 mol%. The respiratory quinone was Q-8 and the dominant fatty acids were identified as iso-C15 : 0 (25.4 %), C16 : 1  ω6c/C16 : 1  ω7c (14.4 %) and iso-C13 : 0 (7.2 %). The main polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Therefore, based on phenotypic, chemotaxonomic and phylogenetic results, strain GYS_M3HT represents a novel species within the genus Ketobacter , for which the name Ketobacter nezhaii sp. nov. is proposed, with the type strain GYS_M3HT (=MCCC 1A13808T=KCTC 72247T).

The family Caulobacteraceae comprises prosthecate bacteria with a dimorphic cell cycle and also non-prosthecate bacteria. Cells of all described species divide by binary fission. Strain 0127_4T was isolated from forest soil in Baden Württemberg (Germany) and determined to be the first representative of the family Caulobacteraceae which divided by budding. Cells of strain 0127_4T were Gram-negative, rod-shaped, prosthecate, motile by means of a polar flagellum, non-spore-forming and non-capsulated. The strain formed small white colonies and grew aerobically and chemo-organotrophically utilizing organic acids, amino acids and proteinaceous substrates. 16S rRNA gene sequence analysis indicated that this bacterium was related to Aquidulcibacter paucihalophilus TH1-2T and Asprobacter aquaticus DRW22-8T with 91.3 and 89.7% sequence similarity, respectively. Four unidentified glycolipids were detected as the major polar lipids and, unlike all described members of the family Caulobacteraceae , phosphatidylglycerol was absent. The major fatty acids were summed feature 8 (C18 : 1ω7c/C18 : 1ω6c), summed feature 9 (iso-C17 : 1ω9c/C16 : 0 10-methyl), C16 : 0 and summed feature 3 (C16 : 1 ω6c/C16 : 1 ω7c). The major respiratory quinone was Q-10. The G+C content of the genomic DNA was 63.5 %. Based on the present taxonomic characterization, strain 0127_4T represents a novel species of a new genus, Terricaulis silvestris gen. nov., sp. nov. The type strain of Terricaulis silvestris is 0127_4T (=DSM 104635T=CECT 9243T).

A Gram-stain-negative aerobic bacterium, strain 11K1T, was isolated from a rhizosphere soil of broad bean collected from Qujing, Yunnan, PR China and characterized by using polyphasic taxonomy. The bacterial cells of strain 11K1T were rod-shaped, motile by two polar flagella and positive for oxidase and catalase. Results of phylogenetic analysis based on 16S rRNA gene sequences revealed that the strain had the highest similarities to Pseudomonas thivervalensis DSM 13194T (99.52 %), Pseudomonas lini CFBP 5737T (99.45 %), Pseudomonas chlororaphis subsp. chlororaphi s NBRC 3904T (99.31 %), Pseudomonas kilonensis DSM 13647T (99.25 %) and Pseudomonas brassicacearum JCM11938T (99.24 %). Multilocus sequence analysis using the 16S rRNA, gyrB, rpoB and rpoD gene sequences demonstrated that strain 11K1T was a member of the Pseudomonas corrugata subgroup within the Pseudomonas fluorescens lineage, but was distant from all closely related species. The average nucleotide identity and in silico DNA–DNA hybridization values were lower than recommended thresholds of 95 and 70 %, respectively, for species delineation. The major isoprenoid quinone of strain 11K1T was ubiquinone (Q-9) and the major cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c) and C17 : 0 cyclo. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, aminophospholipid and two unidentified lipids. Based on the results of phenotypic characterization, phylogenetic analysis and genome comparison, strain 11K1T represents a novel species of the genus Pseudomonas , for which the name Pseudomonas viciae sp. nov. is proposed. The type strain is 11K1T (=GDMCC 1.1743T=KACC 21650T).

A novel Gram-stain-negative, aerobic, rod-shaped and indole acetic acid-producing strain, designated 7209-2T, was isolated from rhizosphere of rape (Brassica napus L.) grown in the Yakeshi City, Inner Mongolia, PR China. The 16S rRNA gene sequence analysis indicated that strain 7209-2T belongs to the genus Rhizobium and is closely related to Rhizobium rosettiformans W3T, Rhizobium ipomoeae shin9-1T and Rhizobium wuzhouense W44T with sequence similarities of 98.2, 98.1 and 97.9 %, respectively. Phylogenetic analysis based on concatenated housekeeping recA and atpD gene sequences showed that strain 7209-2T formed a group together with R. wuzhouense W44T and R. rosettiformans W3T, with sequences similarities of 92.6 and 91.1 %, respectively. The genome size of strain 7209-2T was 5.25 Mb, comprising 5027 predicted genes with a DNA G+C content of 61.2 mol%. The average nucleotide identity and digital DNA–DNA hybridization comparisons among 7209-2T and reference strains for the most closely related species showed values below the accepted threshold for species discrimination. The major fatty acids of strain 7209-2T were summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c) and summed feature 2 (C12 : 0 aldehyde and/or unknown 10.953) . The major polar lipids were found to consist of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and an unidentified aminophospholipid. The predominant ubiquinone was identified as quinone 10. Based on all the above results, strain 7209-2T represents a novel species of the genus Rhizobium , for which the name Rhizobium rhizophilum sp. nov. is proposed with 7209-2T (=CGMCC 1.15691T=DSM 103161T) as the type strain.

This study investigated endophytic nitrogen-fixing bacteria isolated from two species of yam (water yam, Dioscorea alata L.; lesser yam, Dioscorea esculenta L.) grown in nutrient-poor alkaline soil conditions on Miyako Island, Okinawa, Japan. Two bacterial strains of the genus Rhizobium , S-93T and S-62, were isolated. The phylogenetic tree, based on the almost-complete 16S rRNA gene sequences (1476 bp for each strain), placed them in a distinct clade, with Rhizobium miluonense CCBAU 41251T, Rhizobium hainanense I66T, Rhizobium multihospitium HAMBI 2975T, Rhizobium freirei PRF 81T and Rhizobium tropici CIAT 899T being their closest species. Their bacterial fatty acid profile, with major components of C19 : 0 cyclo ω8c and summed feature 8, as well as other phenotypic characteristics and DNA G+C content (59.65 mol%) indicated that the novel strains belong to the genus Rhizobium . Pairwise average nucleotide identity analyses separated the novel strains from their most closely related species with similarity values of 90.5, 88.9, 88.5, 84.5 and 84.4 % for R. multihospitium HAMBI 2975T, R. tropici CIAT 899T, R. hainanense CCBAU 57015T, R. miluonense HAMBI 2971T and R. freirei PRF 81T, respectively; digital DNA–DNA hybridization values were in the range of 26–42 %. Considering the phenotypic characteristics as well as the genomic data, it is suggested that strains S-93T and S-62 represent a new species, for which the name Rhizobium dioscoreae is proposed. The type strain is S-93T (=NRIC 0988T=NBRC 114257T=DSM 110498T).

The taxonomic status of two previously characterized Bradyrhizobium strains (58S1T and S23321) isolated from contrasting habitats in Canada and Japan was verified by genomic and phenotypic analyses. Phylogenetic analyses of five and 27 concatenated protein-encoding core gene sequences placed both strains in a highly supported lineage distinct from named species in the genus Bradyrhizobium with Bradyrhizobium betae as the closest relative. Average nucleotide identity values of genome sequences between the test and reference strains were between 84.5 and 94.2 %, which is below the threshold value for bacterial species circumscription. The complete genomes of strains 58S1T and S23321 consist of single chromosomes of 7.30 and 7.23 Mbp, respectively, and do not have symbiosis islands. The genomes of both strains have a G+C content of 64.3 mol%. Present in the genome of these strains is a photosynthesis gene cluster (PGC) containing key photosynthesis genes. A tRNA gene and its partial tandem duplication were found at the boundaries of the PGC region in both strains, which is likely the hallmark of genomic island insertion. Key nitrogen-fixation genes were detected in the genomes of both strains, but nodulation and type III secretion system genes were not found. Sequence analysis of the nitrogen fixation gene, nifH, placed 58S1T and S23321 in a novel lineage distinct from described Bradyrhizobium species. Data for phenotypic tests, including growth characteristics and carbon source utilization, supported the sequence-based analyses. Based on the data presented here, a novel species with the name Bradyrhizobium cosmicum sp. nov. is proposed with 58S1T (=LMG 31545T=HAMBI 3725T) as the type strain.

Two bacterial strains, 1NT and 5NT, were isolated from hemlock forest soil using a soluble organic matter enrichment. Cells of 1NT (0.65×1.85 µm) and 5NT (0.6×1.85 µm) are Gram-stain-negative, aerobic, motile, non-sporulating and exist as single rods, diplobacilli or in chains of varying length. During growth in dilute media (≤0.1× tryptic soy broth; TSB), cells are primarily motile with flagella. At higher concentrations (≥0.3× TSB), cells of both strains increasingly form non-motile chains, and cells of 5NT elongate (0.57×~7 µm) and form especially long filaments. Optimum growth of 1NT and 5NT occurred at 25–30 °C, pH 6.5–7.0 and <0.5% salinity. Results of comparative chemotaxonomic, genomic and phylogenetic analyses revealed that 1NT and 5NT were distinct from one another and their closest related type strains: Paraburkholderia madseniana RP11T, Paraburkholderia aspalathi LMG 27731T and Paraburkholderia caffeinilytica CF1T. The genomes of 1NT and 5NT had an average nucleotide identity (91.6 and 91.3%) and in silico DNA–DNA hybridization values (45.8%±2.6 and 45.5%±2.5) and differed in functional gene content from their closest related type strains. The composition of fatty acids and patterns of substrate use, including the catabolism of phenolic acids, also differentiated strains 1NT and 5NT from each other and their closest relatives. The only ubiquinone present in strains 1NT and 5NT was Q-8. The major cellular fatty acids were C16 : 0, 3OH-C16 : 0, C17 : 0 cyclo, C19 : 0 cyclo ω8c and summed features 2 (3OH-C14 : 0 / C16 : 1 iso I), 3 (C16 : 1 ω6c/ω7c) and 8 (C18 : 1 ω7c/ω6c). A third bacterium, strain RL16-012-BIC-B, was isolated from soil associated with shallow roots and was determined to be a strain of P. madseniana (ANI, 98.8%; 16S rRNA gene similarity, 100%). Characterizations of strain RL16-012-BIC-B (DSM 110723=LMG 31706) led to proposed emendments to the species description of P. madseniana . Our polyphasic approach demonstrated that strains 1NT and 5NT represent novel species from the genus Paraburkholderia for which the names Paraburkholderia solitsugae sp. nov. (type strain 1NT=DSM 110721T=LMG 31704T) and Paraburkholderia elongata sp. nov. (type strain 5NT=DSM 110722T=LMG 31705T) are proposed.

A taxonomic study of two fluorescent Pseudomonas strains (HJ/4T and SJ/9/1T) isolated from calcite moonmilk samples obtained from two caves in the Moravian Karst in the Czech Republic was carried out. Results of initial 16S rRNA gene sequence analysis assigned both strains into the genus Pseudomonas and showed Pseudomonas yamanorum 8H1T as their closest neighbour with 99.8 and 99.7 % 16S rRNA gene similarities to strains HJ/4T and SJ/9/1T, respectively. Subsequent sequence analysis of rpoD, rpoB and gyrB housekeeping genes confirmed the highest similarity of both isolates to P. yamanorum 8H1T, but phylogeny and sequences similarities implied that they are representatives of two novel species within the genus Pseudomonas . Further study comprising whole-genome sequencing followed by average nucleotide identity and digital DNA–DNA hybridization calculations, repetitive sequence-based PCR fingerprinting with the REP and ERIC primers, automated ribotyping with the EcoRI restriction endonuclease, cellular fatty acid analysis, quinone and polar lipid characterization, and extensive biotyping confirmed clear separation of both analysed strains from the remaining Pseudomonas species and showed that they represent two novel species within the genus Pseudomonas for which the names Pseudomonas karstica sp. nov. (type strain HJ/4T=CCM 7891T=LMG 27930T) and Pseudomonas spelaei sp. nov. (type strain SJ/9/1T=CCM 7893T=LMG 27931T) are suggested.

Bacterial strain CCP-6T, isolated from a freshwater pond in Taiwan, was characterized using a polyphasic taxonomy approach. Phylogenetic analyses based on 16S rRNA gene sequences and an up-to-date bacterial core gene set (92 protein clusters) indicated that strain CCP-6T is affiliated with species in the genus Rhodovarius . Strain CCP-6T was most closely related to Rhodovarius lipocyclicus CCUG 44693T with a 98.9% 16S rRNA gene sequence similarity. Cells were Gram-stain-negative, aerobic, non-motile, rod-shaped and formed light pink-coloured colonies. Optimal growth occurred at 30 °C, pH 6 and in the absence of NaCl. The major fatty acids of strain CCP-6T were C18 : 1 ω7c, C16 : 0 and C19 : 0 cyclo ω8c. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, phosphatidyldimethylethanolamine, phosphatidylmethylethanolamine, diphosphatidylglycerol, three unidentified aminophospholipids and an unidentified phospholipid. The predominant polyamine was spermidine. The major isoprenoid quinone was Q-10. The DNA G+C content of the genomic DNA was 69.3 mol%. Strain CCP-6T showed 85.8% average nucleotide identity and 14.5% digital DNA–DNA hybridization identity with Rhodovarius lipocyclicus CCUG 44693T. On the basis of the genotypic, chemotaxonomic and phenotypic data, strain CCP-6T represents a novel species in the genus Rhodovarius , for which the name Rhodovarius crocodyli sp. nov. is proposed. The type strain is CCP-6T (=BCRC 81095T=LMG 30310T=KCTC 62188T).

A Gram-stain-negative, oxidase- and catalase-positive, facultative anaerobic and rod-shaped bacterium, designated strain SM1977T, was isolated from the surface of coralline algae collected from the intertidal zone at Qingdao, PR China. The strain grew at 10–35 °C, pH 4.5–8.5 and with 1–8.5% (w/v) NaCl. It reduced nitrate to nitrite and hydrolysed Tween 20 and DNA. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain SM1977T was affiliated with the genus Vibrio , having the highest sequence similarity (97.6 %) to the type strain of Vibrio casei , followed by those of another five species (95.6–97.6 %) in the Rumoiensis clade of the genus Vibrio . However, the in silico DNA–DNA hybridization (75.3–75.9 %) and average nucleotide identity (21.6–22.8 %) values of SM1977T against these close relatives were all below the corresponding thresholds to discriminate bacterial species. The major fatty acids were summed feature 3 (C16:1  ω7c and/or C16:1  ω6c), C16:0 and summed feature 8 (C18:1  ω6c and /or C18:1  ω7c). The predominant polar lipids were phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. The sole respiratory quinone was Q-8. The genomic DNA G+C content of strain SM1977T, determined from the obtained whole genomic sequence, was 42.3 mol%. On the basis of the polyphasic results obtained in this study, strain SM1977T is considered to represent a novel species within the genus Vibrio , for which the name Vibrio algicola sp. nov. is proposed. The type strain is SM1977T (=MCCC 1K04351T=KCTC 72847T).

The majority of Suhomyces species have been isolated from fungus-feeding insects and particularly from the gut of beetles. In the present study, seven yeast strains were isolated from the gut of Drosophila species feeding on gleba, the spore-bearing inner mass, of a stinkhorn mushroom belonging to the family Phallaceae. Based on phenotypic, biochemical characterization and sequence analysis of the D1/D2 region of the large subunit rRNA gene and the internal transcribed spacer (ITS) region, two of these yeast strains, DGY3 and DGY4, represented a novel species of the genus Suhomyces. The novel species is closely related to an undescribed species of Candida ST-370 (DQ404513) and with Suhomyces canberraensis, wherein, the novel species differs from S. canberraensis by 40 nucleotide substitutions and three gaps (7.7 % sequence variation) in the D1/D2 region and 50 nucleotide substitutions and seven gaps (13.7 % sequence variation) in the ITS region. Several morphological and physiological differences were also observed between S. canberraensis and the strains obtained during this study. These data support the proposal of Suhomyces drosophilae as a novel species, with DGY3T as the holotype and CBS 16329T and MCC 1871T as ex-type strains.