- Volume 70, Issue 3, 2020

A Gram-staining-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated as JBTF-M21T, was isolated from a tidal flat sediment on the Yellow Sea, Republic of Korea. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences indicated that JBTF-M21T fell within the clade comprising the type strains of species of the genus Erythrobacter . JBTF-M21T exhibited 16S rRNA gene sequence similarities of 97.0–98.4 % to the type strains of Erythrobacter longus , Erythrobacter aquimaris , Erythrobacter nanhaisediminis , Erythrobacter vulgaris , Erythrobacter seohaensis , Erythrobacter litoralis and Erythrobacter citreus and 93.7–96.6 % to the type strains of the other species of the genus Erythrobacter . The ANI and dDDH values between JBTF-M21T and the type strains of E. longus , E. nanhaisediminis , E. seohaensis and E. litoralis were 70.83–72.93 % and 18.0–18.8 %, respectively. Mean DNA–DNA relatedness values between JBTF-M21T and the type strains of E. aquimaris , E. vulgaris and E. citreus were 12–24 %. The DNA G+C content of JBTF-M21T was 57.0 mol%. JBTF-M21T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and C17 : 1ω6c as the major fatty acids. The major polar lipids ofJBTF-M21T were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid. Distinguishing phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that JBTF-M21T is separated from species of the genus Erythrobacter with validly published names. On the basis of the data presented, strain JBTF-M21T is considered to represent a novel species of the genus Erythrobacter , for which the name Erythrobacter insulae sp. nov. is proposed. The type strain is JBTF-M21T (=KACC 19864T=NBRC 113584T).

We herein describe the first novel species within the genus Eikenella since it was established in 1972 by the reclassification of ‘Bacteroides corrodens’ to Eikenella corrodens . From a polymicrobial brain abscess, we encountered an Eikenella isolate, PXXT, that could not validly be named E. corrodens . The isolate grew on blood agar with small, translucent, pitting colonies after 3 days of anaerobic incubation. By reviewing previously collected invasive isolates, we found an additional Eikenella strain, EI-02, from a blood culture exhibiting the same properties as PXXT. Phylogenetic analyses based on both whole genome and individual house-keeping genes confirmed that the two strains allocate in a phylogenetic cluster separate from E. corrodens . Using specific amplification and sequencing of the Eikenella nusG gene, we further detected the novel Eikenella species in six historic brain abscesses previously reported to contain E. corrodens based on 16S metagenomics. Out of 24 Eikenella whole-genome projects available in GenBank, eight cluster together with PXXT and EI-02. These isolates were recovered from brain abscess (n=2), blood (n=1), bone/soft tissue (n=3), parotid gland (n=1) and unknown (n=1). It remains to be investigated whether the new species can cause endocarditis. The average nucleotide identity value between strain PXXT and the E. corrodens type strain ATCC 23834T was 92.1 % and the corresponding genome-to-genome distance value was 47.1 %, both supporting the classification of PXXT as a novel species. For this species we propose the name Eikenella exigua. The type strain of E. exigua is PXXT (DSM 109756T, NCTC 14318T).

A Gram-stain-negative, strictly aerobic, motile, ivory-coloured and rod-shaped bacterium (designated Gsoil 520T) isolated from ginseng cultivation soil was characterized by using a polyphasic approach to clarify its taxonomic position. Strain Gsoil 520T was observed to grow optimally at 30 °C and pH 7.0 on Reasoner's 2A agar medium. The results of phylogenetic analysis, based on 16S rRNA gene sequence similarities, indicated that Gsoil 520T belongs to the genus Devosia of the family Hyphomicrobiaceae and was most closely related to Devosia epidermidihirudinis E84T (98.0 %), Devosia yakushimensis Yak96BT (97.7 %), Devosia neptuniae J1T (97.7 %) and Devosia chinhatensis IPL18T (96.8 %). The complete genome of strain Gsoil 520T is a presumptive circular chromosome of 4 480 314 base pairs having G+C content of 63.7 mol%. A total of 4 354 genes, 4 303 CDS and 43 rRNA genes were assigned a putative function. The major isoprenoid quinone was Q-10. The main polar lipids were phosphatidylglycerol, diphosphatidylglycerol and two unidentified aminolipids (AL1 and AL3). The predominant fatty acids of strain Gsoil 520T were C18 : 1ω7c 11-methyl, C16 : 0 and C18 : 1ω7c/C18 : 1ω6c (summed feature 8) supporting the affiliation of strain Gsoil 520T to the genus Devosia . The low values of DNA–DNA hybridization distinguished strain Gsoil 520T from the recognized species of the genus Devosia . Thus, the novel isolate represents a novel species of the genus Devosia , for which the name Devosia ginsengisoli sp. nov. is proposed, with the type strain Gsoil 520T (=KACC 19440T=LMG 30329T).

An alginate lyase-excreting bacterium, designated strain HB161718T, was isolated from coastal sand collected from Tanmen Port in Hainan, PR China. Cells were Gram-stain-negative rods and motile with a single polar flagellum. Its major isoprenoid quinone was ubiquinone 8 (Q-8), and its cellular fatty acid profile mainly consisted of C16 : 1 ω7c and/or C16 : 1 ω6c, C18 : 1 ω6c and/or C18 : 1 ω7c, C16 : 0, C17 : 0 10-methyl and C16 : 0 N alcohol. The G+C content of the genomic DNA was 44.1 mol%. 16S rRNA gene sequence analysis suggested that strain HB161718T belonged to the genus Alteromonas , sharing 99.5, 99.4, 99.2, 98.9 and 98.5 % sequence similarities to its closest relatives, Alteromonas macleodii JCM 20772T, Alteromonas gracilis 9a2T, Alteromonas australica H17T, Alteromonas marina SW-47T and Alteromonas mediterranea DET, respectively. The low values of DNA–DNA hybridization and average nucleotide identity showed that it formed a distinct genomic species. The combined phenotypic and molecular features supported the conclusion that strain HB161718T represents a novel species of the genus Alteromonas , for which the name Alteromonas portus sp. nov. is proposed. The type strain is HB161718T (=CGMCC 1.13585T=JCM 32687T).

During investigations of spoilage-associated meat microbiota, Pseudomonas isolates were found in two different laboratories showing highest similarities to Pseudomonas lactis DSM 29167T, Pseudomonas paralactis DSM 29164T and Pseudomonas azotoformans DSM 18862T based on 16S rRNA gene sequence comparisons. Phylogenetic analysis of the complete rpoB gene sequences of isolates B4-1T and SpeckC indicated a separate branch with 99.0 and 99.1 % identity, respectively, to their closest relative ( P. lactis DSM 29167T). Further phenotypic and chemotaxonomic characterizations, as well as average nucleotide identity (ANIb) values obtained from the draft genomes, revealed that these isolates could be considered as representing a novel species, with ANIb values of around 94 and 90 % with their closest relatives P. lactis and P. paralactis . Other related species showed ANIb values below 90 %, including Pseudomonas libanensis DSM 17149T, Pseudomonas synxantha DSM 18928T, Pseudomonas orientalis DSM 17489T, Pseudomonas veronii DSM 11331T and P. azotoformans DSM 18862T. Genome-to-genome distance calculations between B4-1T and its closest relative, P. lactis DSM 29167T, showed 62.6 % relatedness. The G+C contents of B4-1T and SpeckC were 59.8 and 59.9 mol%, respectively. The major cellular lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol; the major quinone was Q9. Based on these data, the new species Pseudomonas carnis sp. nov. is proposed, the type strain is B4-1T (=DSM 107652T=LMG 30892T); a second strain is SpeckC (=DSM 107651=LMG 30893).

A thermophilic bacterium, designated SYSU G03088T, was isolated from Moincer hot spring, Tibet, PR China. Polyphasic taxonomic analyses and whole-genome sequencing were used to determine the taxonomic position and genomic profiles of the strain. Phylogenetic analysis using 16S rRNA gene sequence indicated that SYSU G03088T showed highest sequence similarity to Rhodobacter blasticus CGMCC 1.3365T (96.0 % sequence identity). The strain could be differentiated from most recognized species of the genus Rhodobacter by its slightly purple colony colour, distinct phenotypic characters and low ANI values. Cells were Gram-staining negative, and oval-to-rod shaped. Poly-β-hydroxybutyrate and vesicular intracytoplasmic membrane structures were formed inside cells. Growth occurred optimally at 45 °C and pH 7.0. Ubiquinone 10 was the only respiratory quinone. The major fatty acids (>10 %) were C18 : 0, C18 : 1ω7c 11-methyl and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The detected polar lipids of SYSU G03088T included diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylmethylethanolamine. The DNA G+C content of SYSU G03088T was 67.7 % (genome). On the basis of the differences in the phenotypic characteristics and phylogenetic analyses, SYSU G03088T is considered to represent a novel species of the genus Rhodobacter , for which the name Rhodobacter flagellatus sp. nov. is proposed. The type strain is SYSU G03088T (=CGMCC 1.16876T=KCTC 72354T).

The present study aimed to determine the taxonomic positions of strains designated R-5-52-3T, R-5-33-5-1-2, R-5-48-2 and R-5-51-4 isolated from hot spring water samples. Cells of these strains were Gram-stain-negative, non-motile and rod-shaped. The strains shared highest 16S rRNA gene sequence similarity with Vulcaniibacterium thermophilum KCTC 32020T (95.1%). Growth occurred at 28–55 °C, at pH 6–8 and with up to 3 % (w/v) NaCl. DNA fingerprinting, biochemical, phylogenetic and 16S rRNA gene sequence analyses suggested that R-5-52-3T, R-5-33-5-1-2, R-5-48-2 and R-5-51-4 were different strains but belonged to the same species. Hence, R-5-52-3T was chosen for further analysis and R-5-33-5-1-2, R-5-48-2 and R-5-51-4 were considered as additional strains of this species. R-5-52-3T possessed Q-8 as the only quinone and iso-C15:0, iso-C11:0, C16 : 0 and iso-C17 : 0 as major fatty acids. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unidentified polar lipids and two unidentified phospholipids. The genomic G+C content was 71.6 mol%. Heat shock proteins (e.g. Hsp20, GroEL, DnaK and Clp ATPases) were noted in the R-5-52-3T genome, which could suggest its protection in the hot spring environment. Pan-genome analysis showed the number of singleton gene clusters among Vulcaniibacterium members varied. Average nucleotide identity (ANI) values between R-5-52-3T, Vulcaniibacterium tengchongense YIM 77520T and V. thermophilum KCTC 32020T were 80.1–85.8 %, which were below the cut-off level (95–96 %) recommended as the ANI criterion for interspecies identity. Thus, based on the above results, strain R-5-52-3T represents a novel species of the genus Vulcaniibacterium , for which the name Vulcaniibacterium gelatinicum sp. nov. is proposed. The type strain is R-5-52-3T (=KCTC 72061T=CGMCC 1.16678T).

We performed high-quality genome sequencing of eight strains of the species of the genus Tepidimonas and examined the genomes of closely related strains from the databases to understand why Tepidimonas taiwanensis is the only strain of this genus that utilizes glucose and fructose for growth. We found that the assimilation of these hexoses by T. taiwanensis was due to the presence of two transporters that are absent in all other genomes of strains of members of the genus Tepidimonas examined. Some strains lack genes coding for glucokinase, but the Embden–Meyerhof–Parnas pathway appears to be otherwise complete. The pentose phosphate pathway has a complete set of genes, but genes of the Entner–Doudoroff pathway were not identified in the genomes of any of the strains examined. Genome analysis using average nucleotide identity (ANIb), digital DNA–DNA hybridization (dDDH), average amino acid identity (AAI) and phylogenetic analysis of 400 conserved genes was performed to assess the taxonomic classification of the organisms. Two isolates of the genus Tepidimonas from the hot spring at São Pedro do Sul, Portugal, designated SPSP-6T and SPSPC-18 were also examined in this study. These organisms are mixotrophic, have an optimum growth temperature of about 50 ºC, utilize several organic acids and amino acids for growth but do not grow on sugars. Distinctive phenotypic, 16S rRNA gene sequence and genomic characteristics of strains SPSP-6T and SPSPC-18 lead us to propose a novel species based on strain SPSP-6T for which we recommend the name Tepidimonas charontis sp. nov. (=CECT 9683T=LMG 30884T).

A novel Gram-stain-negative, light pink-coloured, short rod-shaped, designated strain W17T, was isolated from a meadow soil sample collected from Xinjiang, PR China. The 16S rRNA gene sequence analysis indicated that strain W17T was related most closely to Skermanella rosea M1T (98.72 %) and Skermanella mucosa 8-14-6T (98.44 %). However, strain W17T showed a low level of DNA–DNA relatedness to S. rosea M1T (32.4±2.6 %) and S. mucosa 8-14-6T (33.5±0.1 %). The genome size of the novel strain was 5.87 Mb and the genomic DNA G+C content was 67.27 mol%. The only respiratory quinone of strain W17T was Q-10. Diphosphatidylglycerol, phosphatidylglycerol. phosphatidylethanolamine and phosphatidylcholine were the major polar lipids. The predominant cellular fatty acids were C18 : 1ω6c and/or C18 : 1ω7c (48.53 %), C16 : 0 (20.88 %) and C18 : 0 (14.92 %). The phylogenetic, phenotypic and chemotaxonomic data showed that strain W17T represents a novel species of the genus Skermanella , for which the name Skermanella pratensis sp. nov. is proposed. The type strain is W17T (=GDMCC 1.1392T=KCTC 62434T).

A Gram-stain-negative, strictly aerobic, rod-shaped and non-motile bacterial strain, designated D-2Q-5-6T, was isolated from a soil sample collected from the Arctic region. Strain D-2Q-5-6T was found to grow at 10–43 °C (optimum, 28 °C), at pH 6.0–9.0 (pH 7.0) and in 0–5 % (w/v) NaCl (0–1 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain D-2Q-5-6T fell into the genus Sphingorhabdus and shared less than 95.8 % identity with all type strains of recognized species of this genus. The major cellular fatty acids of strain D-2Q-5-6T were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c; 31.4 %), summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c; 26.8 %) and C14 : 0 2OH (11.7 %). The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and sphingoglycolipid. The predominant quinone was identified as Q10. The DNA G+C content of strain D-2Q-5-6T was 64.5 mol%. Based on the results of phylogenetic analysis and distinctive phenotypic characteristics, strain D-2Q-5-6T is concluded to represent a novel species of the genus Sphingorhabdus , for which the name Sphingorhabdus soli sp. nov. is proposed. The type strain of the species is D-2Q-5-6T (=MCCC 1A06070T=KCTC 52311T).

Strain 33A1-SZDPT was isolated from a small creek located in Puch, Austria. Strain SP-Ram-0.45-NSY-1T was obtained from a small pond located in Schönramer Moor, Germany. 16S rRNA gene sequence similarities between the type strain of Silvanigrella aquatica , currently the only member of the family Silvanigrellaceae , and strains 33A1-SZDPT and SP-Ram-0.45-NSY-1T of 94.1 and 99.1 %, respectively, suggested affiliation of the two strains with this family. Phylogenetic reconstructions with 16S rRNA gene sequences and phylogenomic analyses with amino acid sequences obtained from 103 single-copy genes suggested that the strains represent a new genus and a new species in the case of strain 33A1-SZDPT (=JCM 32978T=DSM 107810T), and a new species within the genus Silvanigrella in the case of strain SP-Ram-0.45-NSY-1T (=JCM 32975T=DSM 107809T). Cells of strain 33A1-SZDPT were motile, pleomorphic, purple-pigmented on agar plates, putatively due to violacein, and showed variable pigmentation in liquid media. They grew chemoorganotrophically and aerobically and tolerated salt concentrations up to 1.2 % NaCl (v/w). The genome size of strain 33A1-SZDPT was 3.4 Mbp and the G+C content was 32.2 mol%. For this new genus and new species, we propose the name Fluviispira multicolorata gen. nov., sp. nov. Cells of strain SP-Ram-0.45-NSY-1T were motile, pleomorphic, red-pigmented and grew chemoorganotrophically and aerobically. They tolerated salt concentrations up to 1.1 % NaCl (v/w). The genome size of strain SP-Ram-0.45-NSY-1T was 3.9 Mbp and the G+C content 29.3 mol%. For the new species within the genus Silvanigrella we propose the name Silvanigrella paludirubra sp. nov.

A Gram-stain-negative, aerobic, rod-shaped bacterium with peritrichous flagella, designated strain HB161719T, was isolated from coastal sand collected from Tanmen Port in Hainan, PR China. The isolate was found to grow with 2–11 % (w/v) NaCl, at 15–45 °C and pH 6.0–10.0, with an optima of 2–3 % NaCl, 37 °C and pH 7.0, respectively. Chemotaxonomic analysis showed that Q-8 was detected as the sole respiratory quinone and that iso-C15 : 0 and summed features 3, 8 and 9 were the major cellular fatty acids. The G+C content of the genomic DNA was 58.2 mol%. Analysis of the 16S rRNA gene sequence of the strain showed an affiliation with the genus Microbulbifer , sharing 98.7, 98.4, 97.8 and 97.8 % sequence similarities to the closest relatives of Microbulbifer okinawensis ABABA23T, Microbulbifer pacificus SPO729T, Microbulbifer taiwanensis CC-LN1-12T and Microbulbifer gwangyangensis GY2T, respectively. Low DNA–DNA hybridization values showed that it formed a distinct genomic species. The combined phenotypic and molecular features supported that strain HB161719T represents a novel species of the genus Microbulbifer , for which the name Microbulbifer harenosus sp. nov. is proposed. The type strain is HB161719T (=CGMCC 1.13584T=JCM 32688T).

Phylogenetic analysis of the genus Sphingobium had shown that the type strains of Sphingobium paulinellae , Sphingobium algicola and Sphingobium limneticum shared a very close relationship between each other. The 16S rRNA gene sequences similarity values between each other ranged from 99.65 to 99.93 %. Whole genome sequencing was performed and genomic relatedness values between each pair of the species were 97.49–100 % (ANI) and 79.3–100 % (dDDH), respectively, all higher than the threshold values of 95–96 % ANI and 70 % dDDH suggested for species discrimination, and implicated that the type strains should belong to the same species of the genus Sphingobium . The phenotypic and chemotaxonomic characterizations performed in the original descriptions of S. paulinellae and S. algicola also supported the same conclusion. Due to priority of publication Sphingobium paulinellae and Sphingobium algicola Lee and Jeon 2017, should be taken as two later heterotypic synonyms of Sphingobium limneticum Chen et al. 2013. Correspondingly, the species description of Sphingobium limneticum was emended based on this study.

The genus Bartonella (Family: Bartonellaceae ; Order: Rhizobiales; Class: Alphaproteobacteria) comprises facultative intracellular Gram-negative, haemotropic, slow-growing, vector-borne bacteria. Wild rodents and their fleas harbor a great diversity of species and strains of the genus Bartonella , including several zoonotic ones. This genetic diversity coupled with a fastidious nature of the organism results in a taxonomic challenge that has led to a massive collection of uncharacterized strains. Here, we report the genomic and phenotypic characterization of two strains, members of the genus Bartonella (namely Tel Aviv and OE 1–1), isolated from Rattus rattus rats and Synosternus cleopatrae fleas, respectively. Scanning electron microscopy revealed rod-shaped bacteria with polar pili, lengths ranging from 1.0 to 2.0 µm and widths ranging from 0.3 to 0.6 µm. OE 1–1 and Tel Aviv strains contained one single chromosome of 2.16 and 2.23 Mbp and one plasmid of 29.0 and 41.5 Kbp, with average DNA G+C contents of 38.16 and 38.47 mol%, respectively. These strains presented an average nucleotide identity (ANI) of 89.9 %. Bartonella elizabethae was found to be the closest phylogenetic relative of both strains (ANI=90.9–93.6 %). The major fatty acids identified in both strains were C18:1ω7c, C18 : 0 and C16 : 0. They differ from B. elizabethae in their C17 : 0 and C15 : 0 compositions. Both strains are strictly capnophilic and their biochemical profiles resembled those of species of the genus Bartonella with validly published names, whereas differences in arylamidase activities partially assisted in their speciation. Genomic and phenotypic differences demonstrate that OE 1–1 and Tel Aviv strains represent novel individual species, closely related to B. elizabethae , for which we propose the names Bartonella kosoyi sp. nov. and Bartonella krasnovii sp. nov.

A novel bacterium, XHU 5135T, belonging to the genus Aidingimonas , was isolated from a salt lake sample collected in Xinjiang Province, north-west PR China. The isolate was Gram-stain-negative, rod-shaped and non-motile. The strain was catalase-positive and oxidase-negative. Growth occurred at NaCl concentrations of 5–25 % (optimum, 10–13 %), at 13–41 °C (35–37 °C) and at pH 6.0–10.0 (pH 7.0–8.0). The predominant ubiquinone was Q-9. The major fatty acids were C19 : 0 cyclo ω8c and C16 : 0. The G+C content of the genomic DNA was 58.1 mol%. The affiliation of strain XHU 5135T with the genus Aidingimonas was confirmed by 16S rRNA gene sequence comparisons. The closest type strain was Aidingimonas halophile YIM 90637T, which showed a 16S rRNA gene sequence similarity of 97.5 %. The ANI value between XHU 5135T and the closest type strain was 80.01 %. The estimated digital DNA–DNA hybridization estimate value between strain XHU 5135T and the closest type strain was 22.80 %. Phenotypically, the characteristics of XHU 5135T were shown to differ from the most closely related species, A. halophila . On the basis of the data from this polyphasic study, strain XHU 5135T represents a novel species of the genus Aidingimonas , for which the name Aidingimonas lacisalsi sp. nov. is proposed. The type strain is strain XHU 5135T (=CCTCC AB 2016344T=KCTC 42945T=DSM 104700T).

A Gram-stain-negative, non-motile, coccoid-shaped, catalase- and oxidase-positive, non-denitrifying, neutrophilic bacterium designated as strain JC501T was isolated from an epiphytic rhizosphere of an orchid, Aerides maculosa, growing in the Western Ghats of India. Phylogenetic analyses based on the 16S rRNA gene sequence indicated that strain JC501T belonged to the genus Paracoccus and had the highest levels of sequence identity with Paracoccus marinus KKL-A5T (98.9 %), Paracoccus contaminans WPAn02T (97.3 %) and other members of the genus Paracoccus (<97.3 %). Strain JC501T produced indole-3 acetic acid and other indole derivatives from tryptophan. The dominant respiratory quinone was Q-10 and the major fatty acid was C18 : 1ω7c/C18 : 1ω6c, with significant quantities of C18 : 1ω9c, C17 : 0 and C16 : 0. The polar lipids of strain JC501T comprised phosphatidylglycerol, phosphatidylcholine, diphosphatidylglycerol, an unidentified glycolipid, two unidentified aminolipids, two unidentified lipids and four unidentified phospholipids. The genome of strain JC501T was 3.3 Mbp with G+C content of 69.4 mol%. For the resolution of the phylogenetic congruence of the novel strain, the phylogeny was also reconstructed with the sequences of eight housekeeping genes. Based on the results of phylogenetic analyses, low (<85.9 %) average nucleotide identity, digital DNA–DNA hybridization (<29.8 %), chemotaxonomic analysis and physiological properties, strain JC501T could not be classified into any of the recognized species of the genus Paracoccus . Strain JC501T represents a novel species, for which the name Paracoccus aeridis sp. nov. is proposed. The type strain is JC501T (=LMG 30532T=NBRC 113644T).

A Gram-stain-negative, strictly aerobic, oval-shaped, non-motile bacterium with no flagella, designated strain SCR17T, was isolated from a shrimp gill habitat in Tangyin hydrothermal field of Okinawa Trough. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SCR17T formed a lineage within the family ‘ Rhodobacteraceae ’, and shared 16S rRNA gene sequence similarity of 93.2–96.2 % to the related genera Aquicoccus and Roseivivax . Strain SCR17T was able to grow with 0–14 % (w/v) NaCl (optimum, 9–10 %). The sole respiratory quinone was ubiquinone-10. The major polar lipids of strain SCR17T comprised phosphatidylcholine (PC), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), an unidentified aminolipid (AL), an unidentified phospholipid (PL) and an unidentified lipid (L). The predominant fatty acids (more than 10 % of the total fatty acids) were C18 : 1ω7c or/and C18 : 1ω6c, anteiso-C15 : 0, C16 : 0 and C19 : 0 cyclo ω8c . The genomic DNA G+C content of strain SCR17T was 67.7 mol%. Based on polyphasic taxonomic analyses, strain SCR17T is considered to represent a novel species in a new genus of the family ‘ Rhodobacteraceae ’, for which the name Carideicomes alvinocaridis gen. nov., sp. nov. is proposed. The type strain of Carideicomes alvinocaridis is SCR17T (=JCM 33426T=MCCC 1K03732T). The discovery of a novel host-associated bacterium in hydrothermal fields provides an opportunity for the study of host–bacterial symbiosis in extreme environments.

Solar panel surfaces, although subjected to a range of extreme environmental conditions, are inhabited by a diverse microbial community adapted to solar radiation, desiccation and temperature fluctuations. This is the first time a new bacterial species has been isolated from this environment. Strain R4DWNT belongs to the genus Sphingomonas and was isolated from a solar panel surface in Boston, MA, USA. Strain R4DWNT is a Gram-negative, non-motile and rod-shaped bacteria that tested positive for oxidase and catalase and forms round-shaped, shiny and orange-coloured colonies. It is mesophilic, neutrophilic and non-halophilic, and presents a more stenotrophic metabolism than its closest neighbours. The major fatty acids in this strain are C18:1ω7c/C18:1ω6c, C16:1ω7c/C16:1ω6c, C14:0 2OH and C16:0. Comparison of 16S rRNA gene sequences revealed that the closest type strains to R4DWNT are Sphingomonas fennica , Sphingomonas formosensis , Sphingomonas prati , Sphingomonas montana and Sphingomonas oleivorans with 96.3, 96.1, 96.0, 95.9 and 95.7 % pairwise similarity, respectively. The genomic G+C content of R4DWNT is 67.9 mol%. Based on these characteristics, strain R4DWNT represents a novel species of the genus Sphingomonas for which the name Sphingomonas solaris sp. nov. is proposed with the type strain R4DWNT (=CECT 9811T=LMG 31344T).

Two Gram-stain-negative, aerobic, motile and rod-shaped bacteria, one designated as strain AXBT, capable of degrading estrogens, and another, YL23T, capable of degrading estrogen and bisphenol A, were isolated from activated sludge in Xiamen City, PR China. The optimum temperature and pH of both strains were 25–35 °C and pH 7.0–8.0. While strain AXBT could tolerate 3 % (w/v) NaCl, YL23T could only grow between 0–1 % (w/v) NaCl. They contained ubiquinone-10 as the major quinone, spermidine as the major polyamine, summed feature 8 (comprising C18:1ω6c and/or C18:1ω7c) as the major fatty acids and diphosphatidylglycerol, phosphatidylcholine, phosphatidyldimethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid as the major polar lipids. The DNA G+C contents of strains AXBT and YL23T were 63.6 and 63.7 mol%, respectively. Based on the results of 16S rRNA gene sequence analysis, strains AXBT and YL23T belonged to the genus Sphingobium . Strain AXBT was most closely related to Sphingobium chlorophenolicum NBRC 16172T (97.5 %) and Sphingobium chungbukense DJ77T (97.2 %), and strain YL23T was most closely related to S. chlorophenolicum NBRC 16172T (97.4 %) and S. quisquiliarum P25T (97.1 %). Average nucleotide identity values between these two strains and S. chlorophenolicum NBRC 16172T, S. chungbukense DJ77T, Sphingobium chinhatense IP26T, Sphingobium quisquiliarum P25T and Sphingobium japonicum UT26ST were from 80.7 to 85.8 %. In conclusion, strains AXBT and YL23T represent novel species of the genus Sphingobium , for which the names Sphingobium estronivorans sp. nov. and Sphingobium bisphenolivorans sp. nov. are proposed, respectively. The type strains of S. estronivorans and S. bisphenolivorans are AXBT (=MCCC 1K01232T=DSM 102173T) and YL23T (=MCCC 1K02300T=DSM 102172T), respectively.