Pectobacterium zantedeschiae sp. nov. a new species of a soft rot pathogen isolated from Calla lily (Zantedeschia spp.)

Four Gram-negative, rod-shaped pectinolytic bacterial strains designated as 2M, 9M, DPMP599 and DPMP600 were subjected to polyphasic analyses that revealed their distinctiveness from the other Pectobacterium species. Strains 2M and 9M were isolated from Calla lily bulbs cultivated in Central Poland. DPMP599 and DPMP600 strains were isolated from Calla lily leaves from plants grown in Serbia. Phylogenetic analyses based on nine housekeeping genes (gapA, gyrA, icdA, pgi, proA, recA, recN, rpoA, and rpoS), as well as phylogeny based on the 381 most conserved universal proteins confirmed that Pectobacterium zantedeschiae strains were distantly related to the other Pectobacterium, and indicated Pectobacterium atrosepticum, Pectobacterium betavasculorum, Pectobacterium parmentieri and Pectobacterium wasabiae as the closest relatives. Moreover, the analysis revealed that Pectobacterium zantedeschiae strains are not akin to Pectobacterium aroidearum strains, which were likewise isolated from Calla lily.The genome sequencing of the strains 2M, 9M and DPMP600 and their comparison with whole genome sequences of other Pectobacterium type strains confirmed their distinctiveness and separate species status within the genus based on parameters of in silico DNA–DNA hybridization and average nucleotide identity (ANI) values. The MALDI-TOF MS proteomic profile supported the proposition of delineation of the P. zantedeschiae and additionally confirmed the individuality of the studied strains. Based on of all of these data, it is proposed that the strains 2M, 9M, DPMP599, and DPMP600 isolated from Calla lily, previously assigned as P. atrosepticum should be reclassified as Pectobacterium zantedeschiae sp. nov. with the strain 9M^T (PCM2893 = DSM105717 = IFB9009) as the type strain.     

Rhizobium nepotum sp. nov. isolated from tumors on different plant species

Five Gram-negative, rod-shaped, non-spore-forming bacteria were isolated from galls on different plant species in Hungary: strain 39/7(T) from Prunus cerasifera Myrobalan, strain 0 from grapevine var. Ezerjó, strain 7/1 from raspberry var. Findus and in Poland, strain C3.4.1 from Colt rootstock (Prunus avium × Prunus pseudocerasus) and strain CP17.2.2 from Prunus avium. Only one of these isolates, strain 0, is able to cause crown gall on different plant species. On the basis of 16S rRNA gene sequence similarity, the strains cluster together and belong to the genus Rhizobium and their closest relative is Rhizobium radiobacter (99.1%). Phylogenetic analysis of the novel strains using housekeeping genes atpD, glnA, gyrB, recA and rpoB revealed their distinct position separate from other known Rhizobium species and confirmed their relation to Rhizobium radiobacter. The major cellular fatty acids are 18:1 w7c, 16:0, 16:0 3OH, summed feature 2 (comprising 12:0 aldehyde, 16:1 iso I and/or 14:0 3OH) and summed feature 3 (comprising 16:1 w7c and/or 15 iso 2OH). DNA-DNA hybridization of strain 39/7(T) with the type strain of R. radiobacter LMG 140(T) revealed 45% DNA-DNA hybridization. Phenotypic and physiological properties differentiate the novel isolates from other closely related species. On the basis of the results obtained, the five isolates are considered to represent a novel species of the genus Rhizobium, for which the name Rhizobium nepotum sp. nov. (type strain 39/7(T)=LMG 26435(T)=CFBP 7436(T)) is proposed.     

Salinivibrio kushneri sp. nov., a moderately halophilic bacterium isolated from salterns

Ten Gram-strain-negative, facultatively anaerobic, moderately halophilic bacterial strains, designated AL184^T, IB560, IB563, IC202, IC317, MA421, ML277, ML318, ML328A and ML331, were isolated from water ponds of five salterns located in Spain. The cells were motile, curved rods and oxidase and catalase positive. All of them grew optimally at 37 °C, at pH 7.2–7.4 and in the presence of 7.5% (w/v) NaCl. Based on phylogenetic analyses of the 16S rRNA, the isolates were most closely related to Salinivibrio sharmensis BAG^T (99.6–98.2% 16S rRNA gene sequence similarity) and Salinivibrio costicola subsp. costicola ATCC 35508^T (99.0–98.1%). According to the MLSA analyses based on four (gyrB, recA, rpoA and rpoD) and eight (ftsZ, gapA, gyrB, mreB, pyrH, recA, rpoA and topA) concatenated gene sequences, the most closely relatives were S. siamensis JCM 14472^T (96.8–95.4% and 94.9–94.7%, respectively) and S. sharmensis DSM 18182^T (94.0–92.6% and 92.9–92.7%, respectively). In silico DNA–DNA hybridization (GGDC) and average nucleotide identity (ANI) showed values of 23.3–44.8% and 80.2–91.8%, respectively with the related species demonstrating that the ten isolates constituted a single novel species of the genus Salinivibrio. Its pangenome and core genome consist of 6041 and 1230 genes, respectively. The phylogeny based on the concatenated orthologous core genes revealed that the ten strains form a coherent phylogroup well separated from the rest of the species of the genus Salinivibrio. The major cellular fatty acids of strain AL184^T were C_16:0 and C_18:1. The DNA G + C content range was 51.9–52.5 mol% (T_m) and 50.2–50.9 mol% (genome). Based on the phylogenetic-phylogenomic, phenotypic and chemotaxonomic data, the ten isolates represent a novel species of the genus Salinivibrio, for which the name Salinivibrio kushneri sp. nov. is proposed. The type strain is AL184^T (= CECT 9177^T = LMG 29817^T).     

Agrobacterium rosae sp. nov., isolated from galls on different agricultural crops

The plant tumorigenic strain NCPPB 1650^T isolated from Rosa × hybrida, and four nonpathogenic strains isolated from tumors on grapevine (strain 384), raspberry (strain 839) and blueberry (strains B20.3 and B25.3) were characterized by using polyphasic taxonomic methods. Based on 16S rRNA gene phylogeny, strains were clustered within the genus Agrobacterium. Furthermore, multilocus sequence analysis (MLSA) based on the partial sequences of atpD, recA and rpoB housekeeping genes indicated that five strains studied form a novel Agrobacterium species. Their closest relatives were Agrobacterium sp. R89-1, Agrobacterium rubi and Agrobacterium skierniewicense. Authenticity of the novel species was confirmed by average nucleotide identity (ANI) and in silico DNA–DNA hybridization (DDH) comparisons between strains NCPPB 1650^T and B20.3, and their closest relatives, since obtained values were considerably below the proposed thresholds for the species delineation. Whole-genome-based phylogeny further supported distinctiveness of the novel species, that forms together with A. rubi, A. skierniewicense and Agrobacterium sp. R89-1 a well-delineated sub-clade of Agrobacterium spp. named “rubi”. As for other species of the genus Agrobacterium, the major fatty acid of the strains studied was 18:1 w7c (73.42–78.12%). The five strains studied were phenotypically distinguishable from other species of the genus Agrobacterium. Overall, polyphasic characterization showed that the five strains studied represent a novel species of the genus Agrobacterium, for which the name Agrobacterium rosae sp. nov. is proposed. The type strain of A. rosae is NCPPB 1650^T (=DSM 30203^T = LMG 230^T = CFBP 4470^T = IAM 13558^T = JCM 20915^T).     

Thaumasiovibrio occultus gen. nov. sp. nov. and Thaumasiovibrio subtropicus sp. nov. within the family Vibrionaceae,isolated from coral reef seawater off Ishigaki Island,Japan

Two phylogenetically distinct Vibrionaceae strains C4II189^T and C4V358^T isolated from reef seawater off Ishigaki Island, Japan, in 2014 were studied with advanced genome-based taxonomy approaches. All aspects of phylogenetic (16S rRNA phylogeny, MLSA), phenotypic and genetic (ANI, DDH, AAI, and the number of core genes) cohesions between the two identified species were high enough to propose them as members of a new genus within the family Vibrionaceae. Consequently, an eighth genus Thaumasiovibrio gen. nov. is proposed that contains two new species Thaumasiovibrio occultus sp. nov. strain C4II189^T (=DSM 101554^T = JCM 31629^T) (type species) and Thaumasiovibrio subtropicus sp. nov. strain C4V358^T (=DSM 101555^T = JCM 31630^T). Thaumasiovibrio species were phylogenetically distinct from the other Vibrionaceae species based on pyrH gene sequences. The combination of catalase negative, sensitivity to vibriostatic agent O/129, and green colony formation on TCBS for the phylogenetically affiliated strains was the diagnostic features for the current tentative identification of this genus.     

Kocuria uropygioeca sp. nov. and Kocuria uropygialis sp. nov., isolated from the preen glands of Great Spotted Woodpeckers (Dendrocopos major)

Two new species of Gram-positive cocci were isolated from the uropygial glands of wild woodpeckers (Dendrocopos major) originating from different locations in Germany. A polyphasic approach confirmed the affiliation of the isolates to the genus Kocuria. Phylogenetic analysis based on the 16S rRNA gene showed high degree of similarity to Kocuria koreensis DSM 23367^T (99.0% for both isolates). However, low ANIb values of <80% unequivocally separated the new species from K. koreensis. This finding was further corroborated by DNA fingerprinting and analysis of polar lipid profiles. Furthermore, growth characteristics, biochemical tests, MALDI-TOF MS analysis, and G + C contents clearly differentiated the isolates from their known relatives. Besides, the woodpecker isolates significantly differed from each other in their whole-cell protein profiles, DNA fingerprints, and ANIb values. In conclusion, the isolated microorganisms constitute members of two new species, for which the names Kocuria uropygioeca sp. nov. and Kocuria uropygialis sp. nov. are proposed. The type strains are 36^T (DSM 101740^T = LMG 29265^T) and 257^T (=DSM 101741^T = LMG 29266^T) for K. uropygialis sp. nov. and K. uropygioeca sp. nov., respectively.     

Photobacterium malacitanum sp. nov., and Photobacterium andalusiense sp. nov., two new bacteria isolated from diseased farmed fish in Southern Spain

Three strains, H01100409B^T, H01100413B, and H27100402H^T, were isolated from several internal organs of diseased redbanded seabream (Pagrus auriga) reared in Andalusia (Southern Spain). All strains were studied by phenotypic, including chemotaxonomy, and genomic characteristics. Phylogenetic analysis based on concatenated sequences of six housekeeping genes (gyrB, ftsZ, topA, mreB, gapA, and 16S rRNA) supported the inclusion of the strains within the clade Phosphoreum of the genus Photobacterium, and two of the strains (H27100402H^T and H01100409B^T) formed a tight group separated from the closest species P. aquimaris. Genomic analyses, including average nucleotide identity (ANIb and ANIm) and DNA–DNA hybridization (DDH), clearly separated strains H27100402H^T and H01100409B^T from the other species within the clade Phosphoreum with values below the thresholds for species delineation. The chemotaxonomic features (including FAME analysis and MALDI-TOF-MS) of H27100402H^T and H01100409B^T strains confirmed their differentiation from the related taxa. The results demonstrated that strain H01100413B was classified as P. aquimaris and the strains H27100402H^T and H01100409B^T represented a new species each in the genus Photobacterium, for which we propose the names Photobacterium malacitanum sp. nov., type strain H27100402H^T (=CECT 9190^T = LMG 29992^T), and Photobacterium andalusiense sp. nov., type strain H01100409B^T (=CECT 9192^T = LMG 29994^T).     

Physiological and genomic properties of Thermus tenuipuniceus sp. nov., a novel slight reddish color member isolated from a terrestrial geothermal spring

Two closely related, thermophilic bacteria, designated strains YIM 76954^T and YIM 76947, were isolated from the Rehai Geothermal Field, Tengchong, Yunnan province, south-west China. Polyphasic approach and whole genome sequencing were used to determine the taxonomy status and genomic profiles of the novel strains. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two isolates were closely related to Thermus scotoductus SE-1^T (97.1% sequence similarity), and T. amyloliquefaciens YIM 77409^T (96.6%). The strains could be differentiated from most recognized Thermus species by their whitish to slight reddish colony color, distinct DNA fingerprinting profiles and low ANI values. Cells stained Gram-negative, rod-shaped of diameter 0.2–0.5 μm and length 1.5–5.0 μm. Growth occurred at 50–75 °C, pH 6.0–9.0 and in the presence of up to 1.0% (w/v) NaCl concentration. Thiosulfate was found to enhance cell growth, besides improving the intensity of its colony color. Oxygen, nitrate, sulfur, and Fe(III) could be used as terminal electron acceptors for growth. MK-8 was the major respiratory menaquinone. Major fatty acids were iso-C_17:0, iso-C_15:0, anteiso-C_17:0, and anteiso-C_15:0. The genome size was 2.26 Mbp with 65.5% average GC content. A total of 2374 genes was predicted, comprising 2322 protein-coding and 52 RNA genes. On the basis of the polyphasic evidence presented, it is proposed that strain YIM 76954^T represents a novel species of the genus Thermus, for which the name Thermus tenuipuniceus sp. nov. is proposed. The type strain is YIM 76954^T (=JCM 30350^T = KCTC 4677^T).     

Polyphasic characterization of a novel species in the Lactobacillus casei group from cow manure of Taiwan: Description of L. chiayiensis sp. nov.

Two Gram-stain-positive, rod-shaped, non-motile, catalase-negative and facultative anaerobic strains, NCYUAS^T and BCRC 18859 (=NRIC 1947), were isolated from cow manure of Taiwan and coconut juice of Philippines, respectively. Comparative sequence analysis of 16S rRNA gene revealed that the novel strains were members of the genus Lactobacillus. These two strains had 100% of 16S rRNA gene sequence similarity and 98.6% of average nucleotide identity (ANI) value based on whole genome sequences. On the basis of 16S rRNA gene sequence similarity, the type strains of Lactobacillus casei (99.6% similarity), Lactobacillus paracasei subsp. paracasei (99.1%), L. paracasei subsp. tolerans (99.1%), Lactobacillus rhmnosus (99.0%) and ‘Lactobacillus zeae’ (99.7%) were the closest neighbors to these novel strains. The results of phenotypic and chemotaxonomic characterization, multilocus sequence analysis (MLSA) based on the sequences of three housekeeping genes (dnaK, pheS and yycH), whole-genome sequence (WGS)-based comparison by ANI and in silico DNA–DNA hybridization (isDDH), species-specific PCR and whole-cell MALDI-TOF MS spectral pattern analyses demonstrated that the novel two strains represented a single, novel species within the L. casei group, for which the name Lactobacillus chiayiensis sp. nov., is proposed. The type strain is NCYUAS^T (=BCRC 81062^T = NBRC 112906^T).     

Arcobacter bivalviorum sp. nov. and Arcobacter venerupis sp. nov., new species isolated from shellfish

A group of ten Arcobacter isolates (Gram negative, slightly curved motile rods, oxidase positive) was recovered from mussels (nine) and from clams (one). These isolates could not be assigned to any known species using the molecular identification methods specific for this genus (16S rDNA-RFLP and m-PCR). The aim of this study is to establish the taxonomic position of these isolates. The 16S rRNA gene sequence similarity of mussel strain F4(T) to the type strains of all other Arcobacter species ranged from 91.1% to 94.8%. The species most similar to the clams' strain F67-11(T) were Arcobacter defluvii (CECT 7697(T), 97.1%) and Arcobacter ellisii (CECT 7837(T), 97.0%). On the basis of phylogenetic analyses with 16S rRNA, rpoB, gyrB and hsp60 genes, the mussel and clam strains formed two different, new lineages within the genus Arcobacter. These data, together with their different phenotypic characteristics and MALDI-TOF mass spectra, revealed that these strains represent two new species, for which the names Arcobacter bivalviorum (type strain F4(T)=CECT 7835(T)=LMG 26154(T)) and Arcobacter venerupis (type strain F67-11(T)=CECT 7836(T)=LMG 26156(T)) are proposed.     

Paenibacillus ihbetae sp. nov., a cold-adapted antimicrobial producing bacterium isolated from high altitude Suraj Tal Lake in the Indian trans-Himalayas

The assessment of bacterial diversity and bioprospection of the high-altitude lake Suraj Tal microorganisms for potent antimicrobial activities revealed the presence of two Gram-stain-variable, endospore-forming, rod-shaped, aerobic bacteria, namely IHBB 9852^T and IHBB 9951. Phylogenetic analysis based on 16S rRNA gene sequence showed the affiliation of strains IHBB 9852^T and IHBB 9951 within the genus Paenibacillus, exhibiting the highest sequence similarity to Paenibacillus lactis DSM 15596^T (97.8% and 97.7%) and less than 95.9% similarity to other species of the genus Paenibacillus. DNA-DNA relatedness among strains IHBB 9852^T and IHBB 9951 was 90.2%, and with P. lactis DSM 15596^T, was 52.7% and 52.4%, respectively. The novel strains contain anteiso-C_15:0, iso-C_15:0, C_16:0 and iso-C_16:0 as major fatty acids, and phosphatidylglycerol, phosphatidylethanolamine and diphosphatidylglycerol were predominant polar lipids. The DNA G+C content for IHBB 9852T and IHBB 9951 was 52.1 and 52.2 mol%. Based on the results of phenotypic and genomic characterisations, we concluded that strains IHBB 9852^T and IHBB 9951 belong to a novel Paenibacillus species, for which the name Paenibacillus ihbetae sp. nov. is proposed. The type strain is IHBB 9852^T (=MTCC 12459^T = MCC 2795^T = JCM 31131^T = KACC 19072^T; DPD TaxonNumber TA00046) and IHBB 9951 (=MTCC 12458 = MCC 2794 = JCM 31132 = KACC 19073) is a reference strain.     

Neorhizobium tomejilense sp. nov., first non-symbiotic Neorhizobium species isolated from a dryland agricultural soil in southern Spain

We describe for the first time a non-symbiotic species of the recently described genus Neorhizobium, lacking nodulation or nitrogen fixation genes. The strains were isolated from a dryland agricultural soil in southern Spain where no record of legume cultivation is available, thus we propose the name Neorhizobium tomejilense sp. nov. (type strain T17_20^T, LMG 30623^T and CECT 9621^T). N. tomejilense exhibit a clear distinct lineage from the other Neorhizobium species, Neorhizobium galegae, Neorhizobium alkalisoli and Neorhizobium huautlense, based on polyphasic evidence. Phylogenetic marker analysis of 16S rDNA, atpD, glnII, recA, rpoB and thrC genes and genomic identity data derived from the draft genomic sequences showed that N. tomejilense strains clearly separated from the other Neorhizobium species and that N. galegae represents the closest species, with Average Nucleotide Identities (ANIb) ranging from 90% (for type strain HAMBI 540^T) to just under 95.0% (for two N. galegae sv. officinalis strains). Genomes from N. galegae and N. tomejilense, however, clearly differed in important traits, such as the number of rRNA operon copies or the number of tRNAs. Phenotypic characterisation of N. tomejilense also displayed differences with the other Neorhizobium species. Whole-cell matrix-assisted laser-desorption time-of-flight mass spectrometry (WC MALDI-TOF-MS) fingerprint analysis and the dendrogram derived from the fingerprint profiles, showed a clearly distinct group formed by the three N. tomejilense isolates (T17_20^T, T20_22 and T11_12) from the other Neorhizobium especies.     

Corynebacterium heidelbergense sp. nov., isolated from the preen glands of Egyptian geese (Alopochen aegyptiacus)

Two strains (pedersoli^T and girotti) of a new species of bacteria were isolated from the preen glands of wild Egyptian geese (Alopochen aegyptiacus) from the river Neckar in southern Germany in two subsequent years. The strains were lipophilic, fastidious, Gram-positive rods and belonged to the genus Corynebacterium. Phylogenetically, the isolates were most closely related to Corynebacterium falsenii DSM 44353^T which has been found to be associated with birds before. 16S rRNA gene sequence similarity to all known Corynebacterium spp. was significantly <97%. Corresponding values of rpoB showed low levels of similarity <87% and ANIb was <73%. G + C content of the genomic DNA was 65.0 mol% for the type strain of the goose isolates, as opposed to 63.2 mol% in Corynebacterium falsenii. MALDI-TOF MS analysis of the whole-cell proteins revealed patterns clearly different from the related species, as did biochemical tests, and polar lipid profiles. We therefore conclude that the avian isolates constitute strains of a new species, for which the name Corynebacterium heidelbergense sp. nov. is proposed. The type strain is pedersoli^T (=DSM 104638^T = LMG 30044^T).     

Corynebacterium aquatimens sp. nov., a lipophilic Corynebacterium isolated from blood cultures of a patient with bacteremia

An unknown lipophilic coryneform bacterium isolated from the blood cultures of a patient with bacteremia was characterized by phenotypic and molecular genetic methods. Chemical analysis revealed the presence of short chain mycolic acids consistent with the genus Corynebacterium. The DNA G+C content was 60.8mol%. Comparative 16S rRNA gene sequence analysis demonstrated that the isolate represents a new subline within the genus Corynebacterium. The closely phylogenetic relative of the unknown bacterium was found to be C. tuscaniense (97.8% sequence similarity). Partial rpoB gene sequence revealed that strain IMMIB L-2475(T) exhibited 13.5% sequence divergence with C. tuscaniense. The unknown bacterium was distinguished from C. tuscaniense by, DNA-DNA hybridization, cellular fatty acid profiles, MALDI-TOF analyses of cell extracts and biochemical tests. Based on the phylogenetic and phenotypic criteria, it is proposed that this bacterium be classified as new species, Corynebacterium aquatimens sp. nov., and is represented by strain IMMIB L-2475(T) (=DSM 45632(T)=CCUG 61574(T)).     

Acinetobacter cumulans sp. nov., isolated from hospital sewage and capable of acquisition of multiple antibiotic resistance genes

We studied the taxonomic position of six phenetically related strains of the genus Acinetobacter, which were recovered from hospital sewage in China and showed different patterns of resistance to clinically important antibiotics. Whole-genome sequencing of these strains and genus-wide phylogeny reconstruction based on a set of 107 Acinetobacter core genes indicated that they formed a separate and internally cohesive clade within the genus. The average nucleotide identity based on BLAST and digital DNA–DNA hybridization values between the six new genomes were 97.25–98.67% and 79.2–89.3%, respectively, whereas those between them and the genomes of the known species were ≤78.57% and ≤28.5%, respectively. The distinctness of the strains at the species level was also supported by the results of the cluster analysis of the whole-cell protein fingerprints generated by MALDI-TOF MS. Moreover, the strains displayed a catabolically unique profile and could be differentiated from the phylogenetically closest species at least by their inability to grow on d,l-lactate. A total of 18 different genes were found in the six genome sequences which encode resistance to seven classes of antimicrobial agents, including clinically important carbapenems, oxyimino-cephalosporins, or aminoglycosides. These genes occurred in five different combinations, with three to 10 different genes per strain. We conclude that the six strains represent a novel Acinetobacter species, for which we propose the name Acinetobacter cumulans sp. nov. to reflect its ability to acquire and cumulate diverse resistance determinants. The type strain is WCHAc060092^T (ANC 5797^T = CCTCC AB 2018119^T = GDMCC 1.1380^T = KCTC 62576^T).     

Agrobacterium bohemicum sp. nov. isolated from poppy seed wastes in central Bohemia

Two non-pathogenic strains R89-1 and R90^T isolated from poppy seed (Papaver somniferum L.) wastes were phenotypically and genotypically characterized. Multilocus sequence analysis (MLSA) was conducted with six genes (atpD, glnA, gyrB, recA, rpoB, 16S rRNA). The strains represented a new species which clustered with Agrobacterium rubi NBRC 13261^T and Agrobacterium skierniewicense Ch11^T type strains. MLSA was further accompanied by whole-genome phylogeny, in silico DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analyses for both strains. ANI and dDDH values were deep below the species delineation threshold. Phenotypic features of the novel strains unequivocally allowed their differentiation from all other Agrobacterium species. Unlike other agrobacteria, the strains were salt sensitive and were able to biotransform morphine alkaloids. The dominant cellular fatty acids are 18:1 w7c, 16:0 and 12:0 aldehyde/16:1 iso I/14:0 3OH summed in feature 2 and the major respiratory quinine is Q-10 (87%). The DNA G + C content is 56 mol%. Microbial community analysis indicated probable association with P. somniferum plant material. Altogether, these characteristics showed that strains R90^T and R89-1 represent a new species of the genus Agrobacterium which we propose to name Agrobacterium bohemicum. The type strain of A. bohemicum is R90^T (=CCM 8736^T = DSM 104667^T).     

Stappia alba sp. nov., isolated from Mediterranean oysters

Three bacterial strains isolated from oysters recovered at the Spanish Mediterranean coast have been phenotypically and genetically characterized. The results of the phylogenetic analysis based on almost complete 16S rDNA sequences clustered all three strains together with 99.9% average sequence similarity and situated them in the neighbourhood of the genera Stappia, Roseibium and Pannonibacter, Stappia aggregata being their closest neighbour with sequence similarities between 98.8% and 98.9%. DNA-DNA hybridization experiments using DNA of strains 5OM6T and S. aggregata CECT 4269T as reference DNAs confirmed the independent status at species level of the oyster isolates. Phenotypically, they can be distinguished from the closest relatives by the ionic requirements, growth temperatures and use of carbon compounds. We propose these oyster strains constitute a new species of Stappia, for which the name Stappia alba sp. nov. has been chosen, and strain 5OM6T (= CECT 5095T = CIP 108402T) as its type strain.     

Bradyrhizobium arachidis sp. nov., isolated from effective nodules of Arachis hypogaea grown in China

Twenty-three bacterial strains isolated from root nodules of Arachis hypogaea and Lablab purpureus grown in five provinces of China were classified as a novel group within the genus Bradyrhizobium by analyses of PCR-based RFLP of the 16S rRNA gene and 16S–23S IGS. To determine their taxonomic position, four representative strains were further characterized. The comparative sequence analyses of 16S rRNA and six housekeeping genes clustered the four strains into a distinctive group closely related to the defined species Bradyrhizobium liaoningense, Bradyrhizobium yuanmingense, Bradyrhizobium huanghuaihaiense, Bradyrhizobium japonicum and Bradyrhizobium daqingense. The DNA–DNA relatedness between the reference strain of the novel group, CCBAU 051107^T, and the corresponding type strains of the five mentioned species varied between 46.05% and 13.64%. The nodC and nifH genes of CCBAU 051107^T were phylogenetically divergent from those of the reference strains for the related species. The four representative strains could nodulate with A. hypogaea and L. purpureus. In addition, some phenotypic features differentiated the novel group from the related species. Based on all the results, we propose a new species Bradyrhizobium arachidis sp. nov. and designate CCBAU 051107^T (=CGMCC 1.12100^T = HAMBI 3281^T = LMG 26795^T) as the type strain, which was isolated from a root nodule of A. hypogaea and had a DNA G + C mol% of 60.1 (Tm).     

Genomic comparison between members of the Salinibacteraceae family,and description of a new species of Salinibacter (Salinibacter altiplanensis sp. nov.) isolated from high altitude hypersaline environments of the Argentinian Altiplano

The application of tandem MALDI-TOF MS screening with 16S rRNA gene sequencing of selected isolates has been demonstrated to be an excellent approach for retrieving novelty from large-scale culturing. The application of such methodologies in different hypersaline samples allowed the isolation of the culture-recalcitrant Salinibacter ruber second phylotype (EHB-2) for the first time, as well as a new species recently isolated from the Argentinian Altiplano hypersaline lakes. In this study, the genome sequences of the different species of the phylum Rhodothermaeota were compared and the genetic repertoire along the evolutionary gradient was analyzed together with each intraspecific variability. Altogether, the results indicated an open pan-genome for the family Salinibacteraceae, as well as the codification of relevant traits such as diverse rhodopsin genes, CRISPR-Cas systems and spacers, and one T6SS secretion system that could give ecological advantages to an EHB-2 isolate. For the new Salinibacter species, we propose the name Salinibacter altiplanensis sp. nov. (the designated type strain is AN15^T = CECT 9105^T = IBRC-M 11031^T).     

Aeromonas tecta sp. nov., isolated from clinical and environmental sources

Five Aeromonas strains, isolated from both clinical and environmental sources and characterized by a polyphasic approach, including phylogenetic analysis derived from gyrB, rpoD, and 16S rRNA gene sequencing, as well as DNA-DNA hybridization, extensive biochemical and antibiotic susceptibility tests, were recognized as members of an unknown, or undescribed, Aeromonas species. These "Aeromonas eucrenophila-like" strains were closely related to the species A. eucrenophila and Aeromonas encheleia, but they were negative for indole and acid from glycerol tests. Therefore, based on the results of the phylogenetic analyses and DNA-DNA pairing data of these strains, a novel species of the genus Aeromonas is described, for which the name Aeromonas tecta is proposed with isolate F518(T) (CECT7082(T), DSM17300(T), MDC91(T)) as the type strain.