Florfenicol-resistant Brevundimonas sanguinis sp. nov., a novel bacterium isolated from patient blood in South Korea.

An aerobic, Gram-stain-negative, non-motile, non-spore-forming, short rod-shaped bacterial strain, designated NCCP 15609 T, was isolated from the blood sample of a patient in the Republic of Korea. The strain was identified as Brevundimonas diminuta using MALDI-TOF. A phylogenetic tree constructed using 16S rRNA gene sequences revealed that the isolate was of the genus Brevundimonas with 99.8% similarity to B. naejangsanensis. The strain NCCP 15609T genome consisted of one contig with 3,063,090 bp, and had a G+C content of 67.4%. The genome contained 2,949 protein-coding sequences, 52 tRNAs, and 6 rRNAs. The DNA-DNA hybridisation between NCCP 15609T and B. naejangsanensis yielded 92.5% and 49.5% ± 2.6%, respectively, using the average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH). The predominant fatty acids of strain NCCP 15609T were summed feature 8 (C18:1 ω7c/C18:1 ω6c) and C16:0. The isolate contained polar lipids and quinone, corresponding to phosphatidylglycerol, 1,2-di-O-acyl-3-O-[D-glycopyranosyl (1 → 4)-α-D-glucopyranuronosyl] glycerol, and ubiquinone-10, respectively. Based on its phylogenetic, physiological, and chemotaxonomic characteristics, we suggest that NCCP 15609T represents a novel pathogen resource of the genus Brevundimonas and propose to name it Brevundimonas sanguinis sp. nov. The type strain is NCCP 15609T (= DSM 116005T).

Pseudaquidulcibacter saccharophilus gen. nov., sp. nov., a novel member of family Caulobacteraceae, isolated from a water purification facility with supplement of starch as a carbon source.

During a survey of microbial communities in the influent (ambient water) and effluent of a water purification facility with aeration and supplement of starch as carbon source, a novel bacterial strain, designated SZ9T, was isolated from the effluent sample. Colonies of strain SZ9T were small (approximately 0.5-1.0 mm in diameter), creamy-white, circular, smooth, translucent and convex. Cells were facultative anaerobic, motile by means of a single polar flagellum, rod-shaped, multiplied by binary fission, Gram-stain-negative, oxidase-positive and catalase-negative. Growth occurred at 10-40 °C (optimum, 28 °C) and pH 5.5-8.0 (optimum, pH 7.5). The range of NaCl concentration for growth was 0-1.0 % (w/v), with an optimum of 0-0.5 % (w/v). Phylogenetic analysis based on 16S rRNA gene sequences suggested that strain SZ9T formed a lineage within the family Caulobacteraceae of the class Alphaproteobacteria and showed the highest 16S rRNA gene sequence similarities to Aquidulcibacter paucihalophilus TH1-2T (92.44%), followed by Vitreimonas flagellata SYSU XM001T (89.61 %), Asprobacter aquaticus DRW22-8T (89.49 %) and Hyphobacterium vulgare WM6T (89.49%). The predominant fatty acids (>10 % of the total fatty acids) of strain SZ9T was summed feature 3 (comprising C16 : 1 ω6c and/or C16 : 1 ω7c), summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c) and C16 : 0. The sole respiratory quinone was ubiquinone-10, and the major polar lipids were phosphatidylcholine and two unidentified glycolipids. The whole genome of strain SZ9T was 2 842 140 bp in size, including 2769 protein-coding genes, 37 tRNA genes and two rRNA genes, and the genomic G+C content was 41.4 mol%. The orthologous average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between strain SZ9T and other genera within the family Caulobacteraceae were 64.50-66.62 %, 46.96-54.17 % and 27.70-31.70 %, respectively. Therefore, based on the results of phenotypic, chemotaxonomic and phylogenetic analyses, the isolated strain SZ9T could be distinguished from other genera, suggesting that it represents a novel species of a novel genus in the family Caulobacteraceae, for which the name Pseudaquidulcibacter saccharophilus gen. nov., sp. nov is proposed. The type strain is SZ9T (=CCTCC AB2021029T=KCTC 82788T).

Development of isoporous microslit silicon nitride membranes for sterile filtration applications.

The widely used 0.2/0.22 µm polymer sterile filters were developed for small molecule and protein sterile filtration but are not well-suited for the production of large nonprotein biological therapeutics, resulting in significant yield loss and production cost increases. Here, we report on the development of membranes with isoporous sub-0.2 µm rectangular prism pores using silicon micromachining to produce microslit silicon nitride (MSN) membranes. The very high porosity (~33%) and ultrathin (200 nm) nature of the 0.2 µm MSN membranes results in a dramatically different structure than the traditional 0.2/0.22 µm polymer sterile filter, which yielded comparable performance properties (including gas and hydraulic permeance, maximum differential pressure tolerance, nanoparticle sieving/fouling behavior). The results from bacteria retention tests, conducted according to the guidance of regulatory agencies, demonstrated that the 0.2 µm MSN membranes can be effectively used as sterile filters. It is anticipated that the results and technologies presented in this study will find future utility in the production of non-protein biological therapeutics and in other biological and biomedical applications.

Terricaulis silvestris gen. nov., sp. nov., a novel prosthecate, budding member of the family Caulobacteraceae isolated from forest soil.

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).

Asticcacaulis tiandongensis sp. nov., a new member of the genus Asticcacaulis, isolated from a cave soil sample.

A Gram-stain negative, aerobic, motile and rod-shaped bacterium, designated strain 3.1105T, was isolated from a karst district soil sample collected from Tiandong cave, Guizhou province, south-west PR China. The isolate grew at 10-40 °C and pH 5.0-8.0 and tolerated up to 1 % NaCl (w/v) on R2A medium, with optimal growth at 25-30 °C, pH 7.0 and 0 % NaCl (w/v). Cells showed oxidase-positive and catalase-positive reactions. The respiratory quinone was Q-10. The predominant cellular fatty acids contained C18 : 1ω7c 11-methyl, summed feature 8 (C18 : 1ω7c or C18 : 1ω6c), C16 : 0 and C17 : 0. The major polar lipids were phosphatidylglycerol and monoglycosyldiglycerides. The genomic DNA G+C content was 56.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that 3.1105T should be affiliated to the genus Asticcacaulis and showed highest 16S rRNA gene sequence similarity values with Asticcacaulis excentricus CB 48T (96.0 %), Asticcacaulis endophyticus ZFGT-14T (95.3 %) and lower than 95.3 % similarity to other species of the genus Asticcacaulis. The polyphasic taxonomic characteristics indicated that strain 3.1105T represents a novel species of the genus Asticcacaulis, for which the name Asticcacaulis tiandongensis sp. nov., (type strain 3.1105T=KCTC 62978T=CCTCC AB 2018268T) is proposed.

Brevundimonas fluminis sp. nov., isolated from a river.

A Gram-stain-negative, rod-shaped, motile, facultatively aerobic and ivory-pigmented bacterium (designated strain LA-55T) was isolated from a river in the Republic of Korea. On the basis of 16S rRNA gene sequencing, strain LA-55T clustered with species of the genus Brevundimonas and was closely related to B revundimonas kwangchunensis KSL-102T (97.3 %), B revundimonas aurantiaca DSM 4731T (97.1 %), B revundimonas albigilva NHI-13T (97.0 %), B revundimonas balnearis FDRGB2bT (97.0 %) and Brevundimonas aveniformis DSM 17977T (97.0 %). The average nucleotide identity value between strain LA-55T and its closest-related strain was 74.1 %, indicating that strain LA-55T represents a novel species of the genus Brevundimonas. Growth occurred at 15-40 °C on Reasoner's 2A medium in the presence of 0-2 % NaCl (w/v) and at pH 6.0-8.0. The genomic DNA G+C content was 70.5 mol% and ubiquinone 10 (Q-10) was the major respiratory quinone. The major cellular fatty acids (>5 %) were C1 8 :1 ω6c and/or C1 8 :1 ω7c (summed feature 8), C16 : 0, C1 6 :1 ω6c and/or C1 6 :1 ω7c (summed feature 3) and C18 : 1 ω7c 11-methyl. The polar lipids consisted of phosphatidylglycerol, 1,2-di-O-acyl-3-O-[d-glucopyranosyl-(1→4)-α-d-glucopyranuronosyl]glycerol, 1,2-di-O-acyl-3-O-α-d-glucopyranuronosyl glycerol, unidentified aminolipid, unidentified phosphoglycolipid and unidentified lipids. Physiological and biochemical characteristics indicated that strain LA-55T represents a novel species of the genus Brevundimonas, for which the name Brevundimonas fluminis sp. nov. is proposed. The type strain is LA-55T (=KACC 19639T=LMG 30850T).

Bacteria involved in biodegradation of creosote PAH - A case study of long-term contaminated industrial area.

Polycyclic aromatic hydrocarbons (PAH) contained in creosote oil are particularly difficult to remove from the soil environment. Their hydrophobic character and low bioavailability to soil microorganisms affects their rate of biodegradation. This study was performed on samples of soil that were (for over forty years) subjected to contamination with creosote oil, and their metagenome and physicochemical properties were characterized. Moreover, the study was undertaken to evaluate the biodegradation of PAHs by autochthonous consortia as well as by selected bacteria strains isolated from long-term contaminated industrial soil. From among the isolated microorganisms, the most effective in biodegrading the contaminants were the strains Pseudomonas mendocina and Brevundimonas olei. They were able to degrade more than 60% of the total content of PAHs during a 28-day test. The biodegradation of these compounds using AT7 dispersant was enhanced only by Serratia marcescens strain. Moreover, the addition of AT7 improved the effectiveness of fluorene and acenaphthene biodegradation by Serratia marcescens 6-fold. Our results indicated that long-term contact with aromatic compounds induced the bacterial strains to use the PAHs as a source of carbon and energy. We observed that supplementation with surfactants does not increase the efficiency of hydrocarbon biodegradation.

Brevundimonas lutea sp. nov., isolated from lake sediment.

A novel Gram-negative, aerobic, rod-shaped bacterium, designated NS26T, was isolated from a sediment sample collected from Taihu Lake in China. Colonies were orange, circular, smooth and neat-edged on Reasoner's 2A agar. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain NS26T belonged to the genus Brevundimonas and had the closest relationship with Brevundimonas halotolerans DSM 24448T (96.9 %). It grew at 20-37 °C (optimum, 28 °C), pH 5.5-10.5 (pH 7.0) and without NaCl. The major isoprenoid quinone was Q-10. The dominant cellular fatty acids were C18 : 1ω7c, C16 : 0 and C18 : 1ω7c 11-methyl. The polar lipid profile comprised 1,2-diacyl-3-O-(6-phosphatidyl-α-d-glucopyranosyl) glycerol, 1,2-di-O-acyl-3-O-α-d-glycopyranuronosyl glycerol, sulfoquinovosyl diacylglycerol, 1,2-di-O-acyl-3-O-[d-glycopyranosyl-(1→4)-α-d-glucopyranuronosyl] glycerol and phosphatidylglycerol. The G+C content of genomic DNA was 68.4 mol%. The average nucleotide identity value between strain NS26T and B.halotolerans DSM 24448T was 75.6 %. Based on the polyphasic taxonomic study, strain NS26T is suggested to be a novel species, for which the name Brevundimonas lutea sp. nov. is proposed. The type strain is NS26T (=CGMCC 1.13680T=NBRC 113554T).

Phenylobacterium soli sp. nov., isolated from arsenic and cadmium contaminated farmland soil.

A Gram-stain-negative, facultative anaerobic, non-motile and rod-shaped bacterial strain, designated LX32T, was isolated from arsenic and cadmium contaminated farmland soil. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain LX32T was closely related to Phenylobacterium hankyongense HKS-05T (97.7 % sequence similarity), Phenylobacterium kunshanense CCTCC AB 2013085T (97.4 %) and Phenylobacterium deserti CCTCC AB 2016297T (97.1 %). The average nucleotide identity values of the whole genome sequences of LX32T/P. hankyongense HKS-05T, LX32T/P. kunshanense CCTCC AB 2013085T and LX32T/P. deserti CCTCC AB 2016297T were 79.8, 77.9 and 77.5 %, respectively. Its genome size was 4.02 Mb, comprising 3998 predicted genes with a DNA G+C content of 70.1 mol%. The major fatty acids were C15 : 0, C16 : 0 and summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c). The polar lipid profiles consisted of phosphatidylglycerol, aminophospholipid, seven glycolipids and two unidentified polar lipids. The predominantly respiratory quinone was ubiquinone-10. Based on polyphasic analyses, the isolate is considered to represent a novel species of the genus Phenylobacterium, for which the name Phenylobacterium soli sp. nov. is proposed. The type strain is LX32T (=KCTC 62522=CCTCC AB 2018055).

Phenylobacterium parvum sp. nov., isolated from lake water.

A Gram-stain-negative, rod-shaped and aerobic bacterium, designated HYN0004T, was isolated from lake water. The strain grew at 15-35 °C and pH 7.0-9.0 on R2A. The isoprenoid quinone was Q10 and major polar lipids were phosphatidylglycerol and one unidentified glycolipid. The genome was 2.83 Mb with a DNA G+C content of 69.9 mol%. 16S rRNA gene sequence analyses revealed that HYN0004T represented a member of the genus Phenylobacterium and shared sequence similarities with Phenylobacterium conjunctum (97.8 %), Phenylobacterium koreense (97.5 %), Phenylobacterium aquaticum (97.2 %), and Phenylobacteriumheamatophilum (97.0 %). In addition to the low sequence similarities, the phylogenetic tree shapes indicated that HYN0004Trepresents an independent species of this genus. The genomic and phenotypic properties, including small genome size, inability to carry out numerous enzymatic reactions and high ratio of C18 : 1ω6c and/or C18 : 1ω7c in fatty acids, verified the differentiation between HYN0004T and related species. Thus, we propose a novel species of the genus Phenylobacterium, named as Phenylobacterium parvum sp. nov. The type strain is HYN0004T (=KACC 19185T=NBRC 112736T).

Phenylobacterium hankyongense sp. nov., isolated from ginseng field soil.

A Gram-stain-negative, aerobic, non-motile, non-spore-forming and rod-shaped bacterial strain, designated HKS-05T, was isolated from ginseng field soil. This bacterium was characterized to determine its taxonomic position by using the polyphasic approach. HKS-05T grew at 10-37 °C and at pH 6.0-8.0 on R2A agar. On the basis of 16S rRNA gene sequence similarity, HKS-05T was shown to represent a member of the family Caulobacteraceaeand to be related to Phenylobacterium lituiforme FaiI3T (98.1 % sequence similarity), 'Phenylobacterium zucineum' HLK1 (97.9 %), Phenylobacterium muchangponense A8T (97.7 %), Phenylobacteriumcomposti 4T-6T (97.2 %) and Phenylobacterium immobile ET (97.1 %). The major respiratory quinone was Q-10 and the major fatty acids were summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0, and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). The polar lipids were phosphatidylglycerol, unidentified glycolipids and unidentified polar lipids. The G+C content of the genomic DNA was 70.4 mol%. DNA-DNA relatedness values between HKS-05T and its closest phylogenetically neighbours were low. HKS-05T could be differentiated genotypically and phenotypically from the species of the genus Phenylobacterium with validly published names. The isolate therefore represents a novel species, for which the name Phenylobacteriumhankyongense sp. nov. is proposed, with the type strain HKS-05T (=KACC 18628T=LMG 30081T).

Brevundimonas humi sp. nov., an alphaproteobacterium isolated from forest soil.

During a study of bacterial diversity of soil, a novel strain, CA-15T, was isolated from Kyonggi University forest soil. Cells were aerobic, Gram-stain-negative, motile, non-spore-forming, rod-shaped, oxidase-positive and catalase- negative. Tyrosine was not oxidized but produced red pigmentation on an agar palte. Strain CA-15T hydrolysed Tween 60 and DNA. It grew at 15-35 °C (optimum, 25-30 °C), pH 6.0-10.0 (optimum, 7.0-9.0) and at 1.5 % (w/v) NaCl concentration. Phylogenetic analysis based on its 16S rRNA gene sequence indicated that strain CA-15T formed a lineage within the family Caulobacteraceae of the class Alphaproteobacteria that was distinct from various species of the genus Brevundimonas. Brevundimonas bullata DSM 7126T was the closest member of strain CA-15T on the basis of 16S rRNA gene sequence similarity (98.48 %). Q-10 was only an isoprenoid quinone detected for strain CA-15T. The major polar lipids were 1,2-di-O-acyl-3-O-[d-glucopyranosyl-(1→4)-αd-glucopyranuronosyl]glycerol, 1,2-di-O-acyl-3-O-[αd-glucopyranosyl]-sn-glycerol, 1,2-di-O-acyl-3-O-αd-glucopyranuronosylglycerol, 1,2-diacyl-3-O-[6'-phosphatidyl-αd-glucopyranosyl]glycerol and phosphatidylglycerol. The major cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0, C18 : 1ω7c 11-methyl and C17 : 1ω8c. The DNA G+C content of strain CA-15T was 63.6 mol%. The polyphasic characterization indicated that strain CA-15T represents a novel species in the genus Brevundimonas, for which the name Brevundimonas humi sp. nov. is proposed. The type strain of Brevundimonas humi is CA-15T (=KEMB 9005-528T=KACC 19106T=NBRC 112677T).

Brevundimonas mongoliensis sp. nov., A Novel Psychrotolerant Bacterium Isolated from Oil-Contaminated Soil.

Two yellow-coloured, Gram-stain-negative, motile, and rod-shaped bacteria, designated strains R-10-10T and R-10-15 were isolated from oil-contaminated soil. Both strains were able to grow at 4-40 °C, pH 5.5-10.5, and 0-4% (w/v) NaCl concentration. These strains were taxonomically characterized by a polyphasic approach. Based on the 16S rRNA gene sequence analysis, both strains, R-10-10T and R-10-15, could be affiliated to the genus Brevundimonas and shared highest sequence similarity with Brevundimonas staleyi FWC43T (98.8%), Brevundimonas bullata TK0051T (98.6%), and Brevundimonas subvibrioides CB81T (98.3%). The pairwise sequence similarity between strains R-10-10T and R-10-15 was 99.9%. Both strains R-10-10T and R-10-15 contained phosphatidylglycerol, diphosphatidylglycerol, and four unidentified glycolipids as major polar lipids; ubiquinone-10 as sole respiratory quinone; and summed feature 8 (C18:1ω7c and/or C18:1ω6c), C16:0, summed feature 3 (C16:1ω7c and/or C16:1ω6c), and C18:1ω9c as major fatty acids. The genomic DNA G+C content values of strains R-10-10T and R-10-15 were 67.1 and 66.9 mol%, respectively. The DNA-DNA relatedness between R-10-10T and R-10-15 was higher than 70% but the values were less than 55% with closely related reference type strains. The morphological, physiological, chemotaxonomic, and phylogenetic data clearly distinguished strain R-10-10T from its closest phylogenetic neighbors. Thus, strain R-10-10T is considered to represent a novel species of the genus Brevundimonas, for which the name Brevundimonas mongoliensis sp. nov. is proposed. The type strain is R-10-10T (=KEMB 9005-696T = KACC 19387T = JCM 32172T), and strain R-10-15 is considered as an additional strain of the novel species.

Brevundimonas balnearis sp. nov., isolated from the well water of a thermal bath.

A novel alphaproteobacterium was isolated from the well water of a thermal bath at Budapest, Hungary. Phylogenetic analysis of the novel strain showed that this bacterium belongs to a distinct lineage among the genus Brevundimonas. Based on the 16S rRNA gene sequence strain FDRGB2bT showed the highest sequence similarity values to Brevundimonas naejangsanensis BIO-TAS2-2T (97.35 %), Brevundimonas viscosa F3T (97.28 %), Brevundimonas vesicularis LMG 2350T (97.27 %), Brevundimonas nasdae GTC 1043T (97.14 %), Brevundimonas vancanneytii LMG 2337T (97.13 %) and Brevundimonas aurantiaca DSM 4731T (97.13 %). The newly isolated bacterium was strictly aerobic, and its optimum growth occurred at 20-30 °C, between pH 8-9 and without NaCl. Movement was with a single polar flagellum, but the cells could also produce stalks. The major isoprenoid quinone of strain FDRGB2bT was Q-10, the major cellular fatty acids were C18 : 1ω7c and C16 : 0, and the polar lipid profile contained phosphatidylglycerol, diphosphatidylglycerol, two unknown phospholipids and four unknown glycolipids. The characteristic diamino acid in its cell wall is meso-diaminopimelic acid. The G+C content of DNA of the type strain was 69.8 mol%. Strain FDRGB2bT (=DSM 29841T=NCAIM B.02621T) is proposed as the type strain of a novel species with the proposed name Brevundimonas balnearis sp. nov.

Brevundimonas canariensis sp. nov., isolated from roots of Triticum aestivum.

A bacterial strain designated GTAE24T was isolated from a root of wheat growing in soil from the Canary Islands, Spain. Phylogenetic analyses based on 16S rRNA gene sequences placed the isolate in the genus Brevundimonas with Brevundimonas abyssalisTAR-001T as its closest relative at 99.4 % similarity. DNA-DNA hybridization studies showed an average of 38 % relatedness between strain GTAE24T and the type strain of B. abyssalis. Cells were Gram-stain-negative and motile by polar flagella. The strain was positive for oxidase and weakly positive for catalase. Gelatin, starch and casein were not hydrolysed. Growth was supported by many carbohydrates and organic acids as carbon source. Ubiquinone Q-10 was the predominant isoprenoid quinone and C18 : 1ω7c/C18 : 1ω6c (summed feature 8) and C16 : 0 were the major fatty acids. The major polar lipids were phosphatidylglycerol, 1,2-di-O-acyl-3-O-[d-glucopyranosyl-(1,4)-α-d-glucopyranuronosyl] glycerol, 1,2-diacyl-3-O-[6'-phosphatidyl-α-d-glucopyranosyl] glycerol, 1,2-di-O-acyl-3-O-α-d-glucopyranosyl glycerol, and 1,2-di-O-acyl-3-O-α-d-glucopyranuronosyl glycerol. The DNA G+C content was 63.9 mol%. Phylogenetic, chemotaxonomic and phenotypic analyses showed that strain GTAE24T should be considered as representing a novel species of the genus Brevundimonas, for which the name Brevundimonas canariensis sp. nov. is proposed. The type strain is GTAE24T (=LMG 29500T=CECT 9126T).

Phenylobacterium deserti sp. nov., isolated from desert soil.

A novel bacterial strain, designated YIM 73061T, was isolated from the Cholistan desert in Punjab, Pakistan, and characterized by using a polyphasic taxonomic approach. 16S rRNA gene sequence analysis revealed the highest levels of sequence similarity with respect to Phenylobacterium conjunctum FWC21T (97.6 %), Phenylobacterium lituiforme FaiI3T (97.4 %), Phenylobacteriumcomposti 4T-6T (97.0 %) and Phenylobacterium aquaticum W2-3-4T (96.8 %). Cells were Gram-stain-negative, aerobic and motile rods that formed orange colonies. The strain was oxidase- and catalase-positive. Growth occurred at 20-40 °C (optimum, 30-37 °C) at pH 5.0-8.0 (optimum, pH 7.0) and with 0-1 % (w/v) NaCl (optimum, 0-0.5 %). The major cellular fatty acids (>10 %) were summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c) and C16 : 0. The polar lipid profile consisted of phosphatidylglycerol and four unidentified glycolipids. The major isoprenoid quinone was ubiquinone-10 (Q-10). The G+C content of the genomic DNA was 66.8 mol%. Strain YIM 73061T showed low levels of DNA-DNA relatedness to P. conjunctum FWC21T (27.2±2.6 %), P. lituiforme FaiI3T (24.6±1.1 %) and P.composti 4T-6T (18.4±3.1 %). On the basis of phylogenetic inference, chemotaxonomic characteristics and phenotypic data, strain YIM 73061T should be classified as representing a novel species, for which the name Phenylobacterium deserti sp. nov. is proposed. The type strain is YIM 73061T (=DSM 103871T=CCTCC AB 2016297T).

Phenylobacterium panacis sp. nov., isolated from the rhizosphere of rusty mountain ginseng.

A novel, Gram-stain-negative, rod-shaped bacterial strain, designated as DCY109T, was isolated from the rhizosphere of rusty mountain ginseng root located on Hwacheon mountain of Gangwon province, South Korea. 16S rRNA gene sequence analysis revealed that strain DCY109T belonged to the genus Phenylobacterium and was related closely to Phenylobacterium muchangponense KACC 15042T (98.2 % similarity), Phenylobacterium immobile DSM 1986T (96.9 %) and Phenylobacterium koreense KCTC 12206T (96.7 %). The predominant isoprenoid quinone was ubiquinone (Q-10) and the DNA G+C content was 66.9 mol%. The major polar lipids were phosphatidylglycerol, an unidentified glycolipid and an unidentified lipid. The major fatty acids (>10 %) were C16 : 0, summed feature 3 (which comprised C16 : 1ω7c and/or C16 : 1ω6c) and summed feature 8 (which comprised C18 : 1ω7c and/or C18 : 1ω6c). Mean DNA-DNA relatedness between strain DCY109T and its closest relative, P. muchangponense KACC 15042T, was 15.1±3.9 %. Based on the physiological, biochemical, chemotaxonomic and genetic analyses, strain DCY109T is considered to represent a novel species of the genus Phenylobacterium, for which the name Phenylobacterium panacis sp. nov. is proposed. The type strain is DCY109T (=KCTC 42749T=JCM 31045T).

Phenylobacterium aquaticum sp. nov., isolated from the reservoir of a water purifier.

A Gram-reaction-negative, strictly aerobic, non-motile, non-spore-forming, rod-shaped bacterial strain designated W2-3-4T was isolated from the reservoir of a water purifier. This bacterium was characterized to determine its taxonomic position by using a polyphasic approach. Strain W2-3-4T grew well at 25-30 °C on nutrient and R2A agars. On the basis of 16S rRNA gene sequence similarity, strain W2-3-4T was shown to belong to the family Caulobacteraceaeand to be related to Phenylobacterium conjunctumFWC21T (98.0 % sequence similarity) and Phenylobacterium haematophilum CCUG 26751T (97.2 %). Lower sequence similarities were found with the type strains of all other recognized members of the genus Phenylobacterium (95.7-97.1 %). The G+C content of the genomic DNA was 68.7 mol%. The major respiratory quinone was Q-10 and the major fatty acids were summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0, C18 : 1ω7c 11-methyl and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). The polar lipids were phosphatidylglycerol, an unknown phospholipid, four unknown glycolipids and three unidentified polar lipids. DNA-DNA relatedness values between strain W2-3-4Tand its closest phylogenetically neighbours were below 7 %. Strain W2-3-4T could be differentiated genotypically and phenotypically from recognized species of the genus Phenylobacterium. The isolate therefore represents a novel species, for which the name Phenylobacterium aquaticum sp. nov. is proposed, with the type strain W2-3-4T (=KACC 18306T=LMG 28593T).

Identification of anthraquinone-degrading bacteria in soil contaminated with polycyclic aromatic hydrocarbons.

Quinones and other oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) are toxic and/or genotoxic compounds observed to be cocontaminants at PAH-contaminated sites, but their formation and fate in contaminated environmental systems have not been well studied. Anthracene-9,10-dione (anthraquinone) has been found in most PAH-contaminated soils and sediments that have been analyzed for oxy-PAHs. However, little is known about the biodegradation of oxy-PAHs, and no bacterial isolates have been described that are capable of growing on or degrading anthraquinone. PAH-degrading Mycobacterium spp. are the only organisms that have been investigated to date for metabolism of a PAH quinone, 4,5-pyrenequinone. We utilized DNA-based stable-isotope probing (SIP) with [U-(13)C]anthraquinone to identify bacteria associated with anthraquinone degradation in PAH-contaminated soil from a former manufactured-gas plant site both before and after treatment in a laboratory-scale bioreactor. SIP with [U-(13)C]anthracene was also performed to assess whether bacteria capable of growing on anthracene are the same as those identified to grow on anthraquinone. Organisms closely related to Sphingomonas were the most predominant among the organisms associated with anthraquinone degradation in bioreactor-treated soil, while organisms in the genus Phenylobacterium comprised the majority of anthraquinone degraders in the untreated soil. Bacteria associated with anthracene degradation differed from those responsible for anthraquinone degradation. These results suggest that Sphingomonas and Phenylobacterium species are associated with anthraquinone degradation and that anthracene-degrading organisms may not possess mechanisms to grow on anthraquinone.

Phenylobacterium kunshanense sp. nov., isolated from the sludge of a pesticide manufacturing factory.

A novel aerobic, Gram-stain-negative, motile bacterium, designated strain BUT-10(T), was isolated from the sludge of a pesticide manufacturing factory in Kunshan, China. Cells were rod-shaped (0.4-0.45×0.9-1.4 µm) and colonies were white, circular with entire edges and had a smooth surface. The strain grew at 25-37 °C, at pH 6.0-8.0 and with 0-0.5 % NaCl. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain BUT-10(T) was a member of the genus Phenylobacterium, and showed highest sequence similarities to Phenylobacterium muchangponense A8(T) (97.49 %), Phenylobacterium immobile DSM 1986(T) (97.14 %) and Phenylobacterium lituiforme FaiI3(T) (96.34 %). Major fatty acids (>5 %) were summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0 and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). The major isoprenoid quinone was ubiquinone-10. The DNA G+C content was 71.85 mol%. Strain BUT-10(T) showed low DNA-DNA relatedness with P. muchangponense A8(T) (15.7±2.9 %) and P. immobile DSM 1986(T) (12.8±1.1 %). On the basis of the phenotypic, phylogenetic and genotypic data, strain BUT-10(T) is considered to represent a novel species of the genus Phenylobacterium, for which the name Phenylobacterium kunshanense sp. nov. is proposed. The type strain is BUT-10(T) ( = CCTCC AB 2013085(T) = KCTC 42014(T)).