Field electron emission of ZnO nanowire pyramidal bundle arrays

A facile hydrothermal method was adopted to in situ grow ZnO nanowire pyramidal bundle arrays on zinc substrates at low growth temperature without the assistance of catalysts and templates. The bundle arrays were shown to form by sticking of nanowires at their tips. Field electron emission characterization of nanowires bundle arrays revealed a very low turn-on electric field of about 2.3 V/microm and a threshold electric field (corresponding to the field electron emission current density of 10 mA/cm2) of 6.8 V/microm, which are comparable to those observed in carbon nanotube arrays. The bundle arrays also show pronounced long-term field electron emission stability at a high current density. In addition, the formation mechanism of the pyramidal bundled arrays and the origin of the peculiar field electron emission properties were discussed.

Inquilinus ginsengisoli sp. nov., isolated from soil of a ginseng field

A Gram-reaction-negative, chemo-organotrophic, non-motile, non-spore-forming, rod-shaped bacterium (strain Gsoil 080(T)) was isolated from soil collected in a ginseng field in Pocheon Province, South Korea, and was investigated by using a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence analysis showed that strain Gsoil 080(T) was related most closely to Inquilinus limosus strains AU0476(T) and AU1979 (98.9 % similarity to both). Strain Gsoil 080(T) shared ≤91.3 % 16S rRNA gene sequence similarity with the type strains of other recognized species examined. The genus Inquilinus belongs to the family Rhodospirillaceae in the order Rhodospirillales, class Alphaproteobacteria. The predominant ubiquinone was Q-10 and the major fatty acids were summed feature 7 (C(18 : 1)ω9c/ω12t/ω7c) and C(19 : 0) cyclo ω8c. The G+C content of the genomic DNA of strain Gsoil 080(T) was 69.9 mol%. The level of DNA-DNA relatedness between strain Gsoil 080(T) and I. limosus LMG 20952(T) was 12 %. The results of genotypic analyses in combination with chemotaxonomic and physiological data demonstrated that strain Gsoil 080(T) represents a novel species of the genus Inquilinus, for which the name Inquilinus ginsengisoli sp. nov. is proposed. The type strain is Gsoil 080(T) (=KCTC 12574(T) =LMG 23638(T)).

Kribbella ginsengisoli sp. nov., isolated from soil of a ginseng field

A Gram-positive, non-spore-forming, aerobic bacterium, designated Gsoil 001T, was isolated from the soil of a ginseng field in Pocheon province, South Korea. On the basis of 16S rRNA gene sequence analysis, strain Gsoil 001T was shown to belong to the genus Kribbella. The closest phylogenetic relatives were Kribbella koreensis LM 161T (99.0 % 16S rRNA gene sequence similarity), Kribbella flavida KACC 20248T (98.8 %) and Kribbella alba (98.8%). Lower similarity (98.4–96.9 %) was found with the other recognized species of the genus Kribbella. The major quinone was MK-9(H4), the major fatty acids were anteiso-C15 : 0 and iso-C16 : 0 and the major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol. The cell-wall peptidoglycan contained ll-2,6-diaminopimelic acid. These chemotaxonomic data and the high genomic DNA G+C content (66.3 mol%) supported the affiliation of strain Gsoil 001T to the genus Kribbella. The results of physiological and biochemical tests differentiated strain Gsoil 001T genotypically and phenotypically from the Kribbella species with validly published names. Therefore, this isolate represents a novel species, for which the name Kribbella ginsengisoli sp. nov. is proposed, with the type strain Gsoil 001T (=KCTC 19134T =DSM 17941T).

Cyclopamine-induced synophthalmia in sheep: defining a critical window and toxicokinetic evaluation

Cyclopamine, a steroidal alkaloid, from the plant Veratrum californicum is teratogenic, causing a range of different birth defects. The critical window for cyclopamine-induced synophthalmia formation has been reported to be gestational day (GD) 14. The objectives of this study were to better describe cyclopamine-induced craniofacial deformities, to better define the window of susceptibility to synophthalmia formation, and to characterize cyclopamine toxicokinetics in sheep. Ewes were dosed i.v. with purified cyclopamine for toxicokinetic analysis. Another four groups of ewes were dosed orally twice daily with 0.88 g/kg of V. californicum on GD 13, 14 or 15 or consecutively on GD days 13-15. Pregnancy and pre-partum fetal malformations were determined by ultrasound imaging on GD 60. At parturition lambs were assessed for gross malformations. The elimination half-life of cyclopamine in ewes was determined to be 1.1 +/- 0.1 h. The rapid clearance of cyclopamine indicates that ingestion of V. californicum must occur during a very narrow window for synophthalmia formation to occur. Ewes dosed with V. californicum on GD 13 or 14 had lambs with various craniofacial malformations including cyclopia, maxillary dysplasia and mandibular micrognathia. Ewes dosed on GD 15 delivered normal lambs. Ewes dosed consecutively on GD 13-15 were not pregnant at GD 60 and Veratrum-induced embryonic death was assumed to be the cause. Interestingly, lambs with cyclopia were smaller, under-developed and appeared premature even though their twin appeared fully developed. Initial evaluations suggest this was due to placental dysplasia.

Caulobacter ginsengisoli sp. nov., a novel stalked bacterium isolated from ginseng cultivating soil

A Gram negative, aerobic, nonspore-forming, straight or curved rod-shaped bacterium, designated Gsoil 317T, was isolated from soil of a ginseng field in Pocheon Province (South Korea) and was characterized using a polyphasic approach. Cells were dimorphic, with stalk (or prostheca) and nonmotile or nonstalked and motile, by means of a single polar flagellum. Comparative analysis of 16S rRNA gene sequences revealed that strain Gsoil 317T was most closely related to Caulobacter mirabilis LMG 24261T (97.2%), Caulobacter fusiformis ATCC 15257T (97.1%), Caulobacter segnis LMG 17158T (97.0%), Caulobacter vibrioides DSM 9893T (96.8%), and Caulobacter henricii ATCC 15253T (96.7%). The sequence similarities to any other recognized species within Alphaproteobacteria were less than 96.0%. The detection of Q-10 as the major respiratory quinone and a fatty acid profile with summed feature 7 (C18:1 omega7c and/or C18:1 omega9t and/or C18:1 omega12t; 56.6%) and C16:0 (15.9%) as the major fatty acids supported the affiliation of strain Gsoil 317T to the genus Caulobacter. The G+C content of the genomic DNA was 65.5 mol%. DNA-DNA hybridization experiments showed that the DNA-DNA relatedness values between strain Gsoil 317T and its closest phylogenetic neighbors were below 11%. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil 317T should be classified as representing a novel species in the genus Caulobacter, for which the name Caulobacter ginsengisoli sp. nov. is proposed. The type strain is Gsoil 317T (=KCTC 12788T= DSM 18695T).

Sphingobium vulgare sp. nov., isolated from freshwater sediment

A Gram-negative, motile, non-spore-forming bacterial strain, designated HU1-GD12(T), was isolated from freshwater sediment. The strain was characterized by using a polyphasic approach in order to determine its taxonomic position. Comparative analysis of the 16S rRNA gene sequence showed that the isolate constituted a distinct branch within the genus Sphingobium, showing the highest level of sequence similarity with respect to Sphingobium ummariense RL-3(T) (96.2 %). Strain HU1-GD12(T) had a genomic DNA G+C content of 66.8 mol% and Q-10 as the predominant respiratory quinone. Furthermore, the major polyamine component (spermidine) in the cytoplasm and the presence of sphingoglycolipids suggested that strain HU1-GD12(T) belonged to the family Sphingomonadaceae. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain HU1-GD12(T) represents a novel species of the genus Sphingobium, for which the name Sphingobium vulgare sp. nov. is proposed. The type strain is HU1-GD12(T) (=LMG 24321(T)=KCTC 22289(T)).

Coaxial nanocables of p-type zinc telluride nanowires sheathed with silicon oxide: synthesis, characterization and properties

Coaxial nanocables with a single-crystalline zinc telluride (ZnTe) nanowire core and an amorphous silicon oxide (SiO(x)) shell have been synthesized via a simple one-step chemical vapor deposition (CVD) method on gold-decorated silicon substrates. The single-crystal ZnTe nanowire core is in zinc-blende structure along the [111] direction, while the uniform SiO(x) shell fully covers the core with no observable pin-hole or crack. Formation mechanisms of the ZnTe-SiO(x) nanocables are discussed. The ZnTe nanowire core shows p-type electrical properties while the SiO(x) shell acts as an effective insulating layer. The ZnTe-SiO(x) nanocables may have potential applications in nanoscale devices, such as p-type FETs and nanosensors.

Photoconductive properties of selenium nanowire photodetectors

Selenium nanowires with a diameter of about 70 nm and a growth direction along [001] were fabricated via a facile solution method. Photoconductive properties of Se wires were systematically characterized via photodetectors made of single Se nanowire. The photodetectors exhibited a high light on-off current ratio (Ilight/ Idark) of 450, and a fast light response speed of millisecond rise/fall time with excellent stability and reproducibility. It was also observed that the response time strongly depend on the intensity of the illumination light: the rise time and fall time for a typical photodetector is 0.68/1.85, 0.53/1.70, 0.54/1.65, 0.51/1.59, and 0.49/1.58 ms for light intensity of 0.18, 0.26, 0.43, 0.96, and 1.89 mW/cm2, respectively, and the relationship between the light intensity and the photocurrent can be fitted by using a simple power law. The diameters of the nanowire were found to have a significant influence on the response speed with smaller Se nanowires showing higher response speed. Finally, the mechanisms of photoconduction and factors affecting the performance of the photodetectors were elucidated.

Mucilaginibacter daejeonensis sp. nov., isolated from dried rice straw

A novel strain, designated Jip 10(T), isolated from dried rice straw, was characterized by a polyphasic approach to clarify its taxonomic position. The isolate was Gram-negative, facultatively aerobic, heterotrophic, non-motile, non-spore-forming and rod-shaped. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate clustered with the genus Mucilaginibacter in the phylum Bacteroidetes. 16S rRNA gene sequence similarities between strain Jip 10(T) and the type strains of Mucilaginibacter gracilis and Mucilaginibacter paludis were 93.7 and 93.6 %, respectively. The G+C content of the genomic DNA was 48.1 mol%. Chemotaxonomic data [major menaquinone MK-7 and major fatty acids iso-C(15 : 0), iso-C(17 : 0) 3-OH and summed feature 3 (iso-C(15 : 0) 2-OH and/or C(16 : 1)omega7c)] supported the affiliation of strain Jip 10(T) to the genus Mucilaginibacter. However, the results of physiological and biochemical tests allowed phenotypic differentiation of strain Jip 10(T) from other Mucilaginibacter species with validly published names. Therefore, strain Jip 10(T) (=KCTC 12639(T) =LMG 23488(T)) was classified in the genus Mucilaginibacter as the type strain of a novel species, for which the name Mucilaginibacter daejeonensis sp. nov. is proposed.

The fabrication of cubic boron nitride nanocone and nanopillar arrays via reactive ion etching

High-density (2 x 10(9) cm(-2)) uniform arrays of cubic boron nitride (cBN) nanocones and nanopillars with a high aspect ratio were fabricated by employing sequential growth and bias-assisted reactive ion etching using gold nano-dots as an etching mask. The mechanism of formation of the nanopillar and nanocone morphologies was discussed in terms of the relative action of ion bombardment etching and chemical etching due to activated hydrogen plasma constituents. The presented method enabled nanostructuring of cBN surfaces over large areas with great uniformity and reproducibility with a controlled aspect ratio. The unique morphology of the nanostructures offers diverse application opportunities in microelectromechanical devices.

High-quality Graphenes via a facile quenching method for field-effect transistors

Single- and few-layer graphene sheets with sizes up to 0.1 mm were fabricated by simply quenching hot graphite in an ammonium hydrogen carbonate aqueous solution. The identity and thickness of graphene sheets were characterized with transmission electron microscopy, atomic force microscopy, and Raman spectroscopy. In addition to its simplicity and scalability, the present synthesis can produce graphene sheets with excellent qualities in terms of sizes, purity, and crystal quality. The as-produced graphene sheets can be easily transferred to solid substrates for further processing. Field-effect transistors based on individual graphenes were fabricated and shown to have high ambipolar carrier mobilities.

Wurtzite-twinning-induced growth of three-dimensional II-VI ternary alloyed nanoarchitectures and their tunable band gap energy properties

By controlling the growth kinetics, we succeeded in growing wurtzite-twinning-induced three-dimensional (3D) alloyed ternary ZnSexS1-x nanoarchitectures with controlled morphologies and chemical composition via a vapor-solid (VS) process. The lattice constants of the alloyed ZnSexS1-x are linearly dependent on the chemical constituent stoichiometry. Compared with the (102) and (101) twinning in wurtzite structure, the wurtzite {013} twinning with the lowest energy is proved to be an effective route to self-assemble ZnSexS1-x building blocks into bicrystalline and tricrystalline 3D branched nanoarchitectures of different configurations and morphologies. The twinned structure formation is related to growth kinetics at a relatively high temperature. It is the {013} twinning that can accelerate the growth of the 3D nanoarchitectures adapting their specific branching structures, while such characteristic branches are not induced by surface polarity of the II-VI materials. The difference in the final structures and configurations depends on the starting nucleus of the stretching branches, and the type of the nucleated twinning is the key factor in dictating the final nanostructures. Bicrystalline ZnSe0.4S0.6 3D nanoarchitectures are induced by the (013) twin, with the stretched branches growing along [10] direction with an angle of 148 degrees. For the tricrystalline 3D nanoarchitectures, the zinc blende phase is not present at the core of the ZnSe0.4S0.6 3D nanoarchitectures. The stretched branches grow along the [001] direction and share a common twin plane of (013) with an angle of 109.5 degrees between the branches. Cathodoluminescence examination at 10 K reveals that band gap energy can be tuned via chemical composition modification of the alloyed ZnSexS1-x structures. However, a linear relationship does not exist between the near band energy and the chemical composition of the alloyed ZnSexS1-x. This result should be of great significance to realize band gap engineering via chemical composition modification of high-quality alloyed II-VI ternary compound semiconductors.

Characterization of diverse heterocyclic amine-degrading denitrifying bacteria from various environments

Although, there have been many published bacterial strains aerobically degrading the heterocyclic amine compounds, only one strain to date has been reported to degrade pyrrolidine under denitrifying conditions. In this study, denitrifying bacteria degrading pyrrolidine and piperidine were isolated from diverse geological and ecological origins through selective enrichment procedures. Based on the comparative sequence results of 16S rRNA genes, 30 heterocyclic amine-degrading isolates were grouped into ten distinct phylotypes belonging to the genera Thauera, Castellaniella, Rhizobium, or Paracoccus of the phylum Proteobacteria. The representative isolates of individual phylotypes were characterized by phylogenetic, phenotypic and chemotaxonomical traits, and dissimilatory nitrite reductase gene (nirK and nirS). All isolates completely degraded pyrrolidine and piperidine under both aerobic and anaerobic conditions. The anaerobic degradations were coupled to nitrate reduction. A metabolic pathway for the anaerobic degradation of pyrrolidine was proposed on the basis of enzyme activities implicated in pyrrolidine metabolism from three isolates. The three key pyrrolidine-metabolizing enzymes pyrrolidine dehydrogenase, gamma-aminobutyrate/alpha-ketoglutarate aminotransferase, and succinic semialdehyde dehydrogenase, were induced by heterocyclic amines under denitrifying conditions. They were also induced in cells grown aerobically on heterocyclic amines, suggesting that the anaerobic degradation of pyrrolidine shares the pathway with aerobic degradation.

The effect of postoperative immobilization on short-segment fixation without bone grafting for unstable fractures of thoracolumbar spine

BACKGROUND

Controversy regarding the fixation level for the management of unstable thoracolumbar spine fractures exists. Often poor results are reported with short-segment fixation. The present study is undertaken to compare the effect of fixation level and variable duration of postoperative immobilization on the outcome of unstable thoracolumbar burst fractures treated by posterior stabilization without bone grafting.

PATIENTS AND METHODS

A randomized, prospective, and consecutive series was conducted at a tertiary level medical center. Thirty-six neurologically intact (Frankel type E) thoracolumbar burst fracture patients admitted at our institute between February 2003 and December 2005 were randomly divided into three groups. Group I (n = 15) and II (n = 11) patients were treated by short-segment fixation, while Group III (n = 10) patients were treated by long-segment fixation. In Group I ambulation was delayed to 10th-14th postoperative day, while group II and III patients were mobilized on third postoperative day. Anterior body height loss (ABHL) percentage and increase in kyphosis as measured by Cobb's angle were calculated preoperatively, postoperatively, and at follow-up. Denis Pain Scale and Work Scales were obtained during follow-up.

RESULTS

Mean follow-up was 13.7 months (range 3-27 months). At the final follow-up the mean ABHL was 4.73% in group I compared with 16.2% in group II and 6.20% in group III. The mean Cobb's angle loss was 1.8 degrees in group I compared with 5.91 degrees in group II and 2.3 degrees in group III. The ABHL difference between groups I and II was significant (P = 0.0002), while between groups I and III was not significant (P = 0.49).

CONCLUSION

The short-segment fixation with amenable delayed ambulation is a valid option for the management of thoracolumbar burst fractures, as radiological results are comparable to that of long-segment fixation with the advantage of preserving maximum number of motion segments.

Cell-culture-based immunochromatography for rapid detection of group A human rotaviruses in aquatic environments

In an effort to detect rapidly and conveniently the infectious waterborne group A human rotaviruses that cause diarrhea in infants and children, the authors developed the first-ever cell-culture-based immunochromatography method. An immunochromatography kit interacted only with the human rotaviruses VP6 antigen, and the cell-culture-based immunochromatography detected group A human rotaviruses with a sensitivity as low as 1.99 TCID50 ml(-1). This detection sensitivity was similar to that of the cytopathic effect-based method. There were no actual differences between the sensitivity of this method and that of the real-time reverse transcription polymerase chain reaction method, which is known as a method with a relatively high sensitivity. Furthermore, while cell culture detection methods, that is total culturable virus assay, can determine only the presence of infectious waterborne viruses, the cell-culture-based immunochromatography is advantageous for the accurate detection of group A human rotaviruses. Compared with the real-time reverse transcription polymerase chain reaction method, the cell-culture-based immunochromatography is advantageous because it requires a relatively simple process that enables easy quality controls and low test costs. Thus, this study proposed a new method for the identification of group A human rotaviruses, and it is suggested that this cell-culture-based immunochromatography may be applied to detect group A human rotaviruses in aquatic environments.

Vertically aligned p-type single-crystalline GaN nanorod arrays on n-type Si for heterojunction photovoltaic cells

Vertically aligned Mg-doped GaN nanorods have been epitaxially grown on n-type Si substrate to form a heterostructure for fabricating p-n heterojunction photovoltaic cells. The p-type GaN nanorod/n-Si heterojunction cell shows a well-defined rectifying behavior with a rectification ratio larger than 10(4) in dark. The cell has a high short-circuit photocurrent density of 7.6 mAlcm2 and energy conversion efficiency of 2.73% under AM 1.5G illumination at 100 mW/cm2. Moreover, the nanorod array may be used as an antireflection coating for solar cell applications to effectively reduce light loss due to reflection. This study provides an experimental demonstration for integrating one-dimensional nanostructure arrays with the substrate to directly fabricate heterojunction photovoltaic cells.

Deinococcus aquaticus sp. nov., isolated from fresh water, and Deinococcus caeni sp. nov., isolated from activated sludge

The taxonomic positions of two environmental isolates from South Korea were established using a combination of genotypic and phenotypic data. The organisms, designated PB314(T) and Ho-08(T), were Gram-negative, rod-shaped and non-spore-forming and had chemotaxonomic properties consistent with their classification in the genus Deinococcus 16S rRNA gene tree, the highest sequence similarities being shown to the type strains of Deinococcus grandis (96.3-96.7 %) and Deinococcus indicus (96.3-96.4 %). The isolates shared relatively high 16S rRNA gene sequence similarity (98.1 %) but had a DNA-DNA relatedness value of only 22 %. Chemotaxonomic data revealed that both strains possess quinone system MK-8 as the predominant compound, C(16 : 1)omega7c and C(16 : 0) as major fatty acids and ornithine as a diamino acid in the peptidoglycan structure, corroborating our assignment of the strains to the genus Deinococcus. The results of phylogenetic analyses based on 16S rRNA gene sequences, DNA-DNA relatedness values and physiological and biochemical tests clearly demonstrated that the two strains represent distinct species. On the basis of these data, two novel species, Deinococcus aquaticus sp. nov. (type strain PB314(T) =KCTC 12552(T) =NBRC 101311(T)) and Deinococcus caeni sp. nov. (type strain Ho-08(T) =KCTC 12553(T) =NBRC 101312(T)), are proposed.

Chelatococcus daeguensis sp. nov., isolated from wastewater of a textile dye works, and emended description of the genus Chelatococcus

A Gram-negative, non-spore-forming, rod-shaped bacterial strain, K106(T), was isolated from wastewater collected from a textile dye works in Korea. Strain K106(T) grew optimally at pH 7.0-7.5 and 30-37 degrees C in the presence of 0-1.0% (w/v) NaCl. A phylogenetic tree based on 16S rRNA gene sequences showed that strain K106(T) joined the type strain of Chelatococcus asaccharovorans with a bootstrap resampling value of 99.9%. The predominant ubiquinone of strain K106(T) was Q-10. The fatty acid profile of strain K106(T) was similar to that of C. asaccharovorans DSM 6462(T). Major polar lipids of strain K106(T) and C. asaccharovorans DSM 6462(T) were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, two aminolipids and two unidentified phospholipids. sym-Homospermidine, spermidine and putrescine were major polyamines. The DNA G+C content was 68.3 mol%. Strain K106(T) exhibited 16S rRNA gene sequence similarity of 96.6% to the type strain of C. asaccharovorans. DNA-DNA relatedness data and differential phenotypic properties, particularly differences in cell morphology and the ability to utilize nitrilotriacetate, demonstrated that strain K106(T) can be differentiated from C. asaccharovorans. On the basis of phenotypic, phylogenetic and genetic data, strain K106(T) represents a novel species of the genus Chelatococcus, for which the name Chelatococcus daeguensis sp. nov. is proposed. The type strain is K106(T) (=KCTC 12979(T) =CCUG 54519(T)).

Castellaniella caeni sp. nov., a denitrifying bacterium isolated from sludge of a leachate treatment plant

A Gram-negative, non-motile, facultatively anaerobic, denitrifying bacterial strain, designated Ho-11(T), was isolated from sludge of a leachate treatment plant and was characterized taxonomically by using a polyphasic approach. The G+C content of the genomic DNA was 63.5 mol%. Strain Ho-11(T) contained ubiquinone Q-8 as the major respiratory lipoquinone and putrescine as the predominant polyamine. The major fatty acids were summed feature 4 (C(16:1)omega7c and/or iso-C(15:0) 2-OH; 29.3%), C(16:0) (28.0%) and summed feature 7 (C(18:1)omega7c, C(18:1)omega9t and/or C(18:1)omega12t; 19.8%). Comparative 16S rRNA gene sequence analysis showed that strain Ho-11(T) belonged to the family Alcaligenaceae, class Betaproteobacteria, and joined the evolutionary radiation enclosed by the genus Castellaniella. 16S rRNA gene sequence similarities between strain Ho-11(T) and the type strains of the two recognized species of the genus, Castellaniella denitrificans DSM 11046(T) and Castellaniella defragrans DSM 12141(T), were 97.8 and 97.4%, respectively. Levels of similarity between strain Ho-11(T) and all other recognized species of the family Alcaligenaceae were below 95.6%. Strain Ho-11(T) exhibited relatively low levels of DNA-DNA relatedness with respect to C. denitrificans DSM 11046(T) (33%) and C. defragrans DSM 12141(T) (28%). On the basis of its phenotypic and genotypic properties together with phylogenetic distinctiveness, strain Ho-11(T) (=KCTC 12197(T)=LMG 23411(T)) should be classified in the genus Castellaniella as the type strain of a novel species, for which the name Castellaniella caeni sp. nov. is proposed.

Cellulomonas chitinilytica sp. nov., a chitinolytic bacterium isolated from cattle-farm compost

A bacterial strain, designated X.bu-b T, with chitin-, xylan-, cellulose- and starch-degrading activities, was isolated from compost at a cattle farm near Daejeon, Republic of Korea. The strain comprised Gram-positive, aerobic or facultatively anaerobic, non-motile, rod-shaped bacteria. On the basis of an analysis of 16S rRNA gene sequences, the phylogenetic position of X.bu-b T was within the genus Cellulomonas, and the strain exhibited relatively high sequence similarities with respect to Cellulomonas biazotea DSM 20112T (98.1 %), C. cellasea DSM 20118T (98.1 %), C. fimi DSM 20113T (98.0 %), C. terrae DB5T (97.9 %), C. humilata ATCC 25174T (97.7 %), C. xylanilytica XIL11 T (97.5 %), C. uda DSM 20107T (97.4 %), C. gelida DSM 20111 T (97.3 %), C. iranensis OT (97.3 %) and C. flavigena DSM 20109T (97.0 %). The phylogenetic distance from other Cellulomonas species with validly published names was greater than 3 % (i.e. less than 97.0 % sequence similarity). Chemotaxonomic data also supported the classification of strain X.bu-b T within the genus Cellulomonas: L-ornithine was the cell-wall diamino acid, anteiso-C15:0 and anteiso-C17:0 were the major fatty acids, rhamnose, galactose, xylose and ribose were the cell-wall sugars, MK-9(H4) was the predominant menaquinone and diphosphatidylglycerol and phosphatidylglycerol were present in the polar lipids. The G+C content of the genomic DNA was 73.6 mol%. DNA-DNA hybridization experiments showed that the values for DNA-DNA relatedness between strain X.bu-b T and the phylogenetically closest neighbours were below 23 %. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain X.bu-b T represents a novel species of the genus Cellulomonas, for which the name Cellulomonas chitinilytica sp. nov. is proposed. The type strain is X.bu-b T (=KCTC 19133T =DSM 17922T).

Pedobacter agri sp. nov., from soil

A Gram-negative strain, PB92(T), which belongs to the family Sphingobacteriaceae, was isolated from soil (Daejeon, Korea). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain PB92(T) was associated with the genus Pedobacter and was most closely related to the type strains Pedobacter sandarakinus DS-27(T) (97.7 %), Pedobacter roseus CL-GP80(T) (97.5 %) and Pedobacter suwonensis 15-52(T) (97.5 %). The major cellular fatty acid components of strain PB92(T) were C(16 : 1)omega7c (21.4 %), iso-C(15 : 0) (30.8 %), iso-C(17 : 0) 3-OH (9.3 %) and iso-C(15 : 0) 2-OH (11.2 %). The G+C content of the genomic DNA from strain PB92(T) was 41.4 mol%. Analysis of 16S rRNA gene sequences, as well as physiological and biochemical tests, indicated that strain PB92(T) could be differentiated genotypically and phenotypically from reference species of the genus Pedobacter. Strain PB92(T) (=KCTC 12511(T)=DSM 19486(T)) is proposed as the type strain of a novel species, Pedobacter agri sp. nov.

Lysobacter ginsengisoli sp. nov., a novel species isolated from soil in Pocheon Province, South Korea

A Gram-negative, aerobic, rod-shaped, nonspore-forming bacterial strain, designated Gsoil 357T, was isolated from soil sample of a ginseng field in Pocheon Province (South Korea). The isolate contained Q-8 as the predominant ubiquinone and iso-C16:0, iso-C17:1 9c, and iso-C15:0 as the major fatty acids. The G+C content of the genomic DNA was 69.3mol%. A phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Gsoil 357T was most closely related to Lysobacter gummosus (97.6%) and Lysobacter antibioticus (97.6%). However, the DNA-DNA relatedness value between strain Gsoil 357T and its phylogenetically closest neighbors was less than 17%. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil 357T should be classified as representing a novel species in the genus Lysobacter, for which the name Lysobacter ginsengisoli sp. nov. is proposed. The type strain is Gsoil 357T (=KCTC 12602T=DSM 18420T).

p-Type ZnO nanowire arrays

Well-aligned ZnO nanowire (NW) arrays with durable and reproducible p-type conductivity were synthesized on alpha-sapphire substrates by using N2O as a dopant source via vapor-liquid-solid growth. The nitrogen-doped ZnO NWs are single-crystalline and grown predominantly along the [110] direction, in contrast to the [001] direction of undoped ZnO NWs. Electrical transport measurements reveal that the nondoped ZnO NWs exhibit n-type conductivity, whereas the nitrogen-doped ZnO NWs show compensated highly resistive n-type and finally p-type conductivity upon increasing N2O ratio in the reaction atmosphere. The electrical properties of p-type ZnO NWs are stable and reproducible with a hole concentration of (1-2) x 10(18) cm(-3) and a field-effect mobility of 10-17 cm2 V(-2) s(-1). Surface adsorptions have a significant effect on the transport properties of NWs. Temperature-dependent PL spectra of N-doped ZnO NWs show acceptor-bound-exciton emission, which corroborates the p-type conductivity. The realization of p-type ZnO NWs with durable and controlled transport properties is important for fabrication of nanoscale electronic and optoelectronic devices.

Hymenobacter soli sp. nov., isolated from grass soil

A Gram-negative, strictly aerobic, non-spore-forming, rod-shaped, red-pink bacterium, designated strain PB17T, was isolated from grass soil in the Republic of Korea and its taxonomic position was investigated by means of a polyphasic approach. Phylogenetic analysis of 16S rRNA gene sequences showed that strain PB17T belonged to the genus Hymenobacter. Sequence similarities between strain PB17T and the type strains of Hymenobacter species with validly published names ranged from 90.1 to 91.8 %. The predominant cellular fatty acids in strain PB17T were iso-C15 : 0, summed feature 4 (iso-C15 : 0 2-OH and/or C16 : 1 omega 7c), C16 : 1 omega 5c and anteiso-C15 : 0. The DNA G+C content was 58.8 mol%. The results of phylogenetic, chemotaxonomic and phenotypic characterization indicated that strain PB17T can be distinguished from all known Hymenobacter species and represents a novel species, for which the name Hymenobacter soli sp. nov. is proposed. The type strain is PB17T (=KCTC 12607T =LMG 24240T).

The effect of body condition on serum concentrations of two teratogenic alkaloids (anagyrine and ammodendrine) from lupines (Lupinus species) that cause crooked calf disease

Several species of lupine (Lupinus spp.) are toxic to livestock, causing death losses in sheep and cattle but more commonly crooked calf disease in pregnant range cows. The major toxic alkaloids in lupine are of the quinolizidine alkaloid group and include the teratogen anagyrine, which is primarily responsible for crooked calf disease. Lupines also contain teratogenic piperidine alkaloids including ammodendrine. Previous work in sheep has shown that lupine alkaloid clearance may be influenced by the animal's physiological status. Therefore, the purpose of this study was to determine if differences in body condition of cattle would alter the absorption and elimination of anagyrine or ammodendrine given in a single oral dose as Lupinus leucophyllus or Lupinus sulphureus, respectively. Mature non-lactating cows in low body condition (LBC, n = 4) and high body condition (HBC, n = 4) received a single dose of dry ground lupine plant (2.0 g/kg of BW) via oral gavage. Lupinus leucophyllus (anagyrine) was dosed first; then after 21 d the same animals were dosed with L. sulphureus (ammodendrine). Blood samples were taken via jugular venipuncture 0 to 60 h after dosing. Serum anagyrine and ammodendrine concentrations were evaluated. The concentration of anagyrine was greater (P = 0.001) in the HBC group and peaked 2 h after dosing versus 12 h in LBC cows. Similarly for ammodendrine, the alkaloid concentration peaked at 3 h after dosing for the HBC group compared with 6 h for the LBC group (P = 0.001). Area under the curve tended to differ (P <or= 0.11) for both alkaloids in the HBC group compared with the LBC group. There were also differences in the maximum serum anagyrine (P = 0.02) and ammodendrine (P = 0.06) concentrations. Elimination half-life (E1/2) tended to differ (P = 0.12) between the HBC and LBC groups for ammodendrine. The kinetic profiles suggest that body condition influenced the disposition of these alkaloids. This study also suggests that body condition may impact the risk of toxicity, teratogenicity, or both of these alkaloids.

Sphingopyxis panaciterrae sp. nov., isolated from soil from ginseng field

A Gram-negative, strictly aerobic, motile bacterial strain, designated Gsoil 124T, was isolated from a soil sample taken from a ginseng field in Pocheon Province (South Korea). The isolate contained Q-10 as the predominant lipoquinone, plus C18:1 7c and summed feature 4 (C16:1 6c and/or iso- C15:0 2-OH) as the major fatty acids. The G+C content of the genomic DNA was 68.1 mol%, and the major polar lipids consisted of sphingoglycolipid, phosphatidylglycerol, phosphatidylcholine, and phosphatidylethanolamine. A comparative 16S rRNA gene sequence analysis showed that strain Gsoil 124T was most closely related to Sphingopyxis chilensis (98.7%), Sphingopyxis alaskensis (98.2%), Sphingopyxis witflariensis (98.2%), Sphingopyxis taejonensis (98.0%), and Sphingopyxis macrogoltabida (97.6%). However, the DNA-DNA relatedness between strain Gsoil 124T and its phylogenetically closest neighbors was less than 22%. Thus, on the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil 124T should be classified as representing a novel species in the genus Sphingopyxis, for which the name Sphingopyxis panaciterrae sp. nov. is proposed. The type strain is Gsoil 124T (=KCTC 12580T=LMG 24003T).

Burkholderia sediminicola sp. nov., isolated from freshwater sediment

A Gram-negative, motile and rod-shaped bacterium, designated HU2-65W(T), was isolated from freshwater sediment. The strain possessed ubiquinone 8 as the predominant isoprenoid quinone and contained major amounts of omega7-cis-octadecenoic acid and hexadecanoic acid in its cell envelope, which are properties shared by members of the genus Burkholderia. On the basis of 16S rRNA gene sequence similarity, strain HU2-65W(T) was most closely related to the type strain of Burkholderia xenovorans (98.4 %). The DNA G+C content of strain HU2-65W(T) was 61.2 mol%, and DNA-DNA relatedness values to type strains of closely related species were found to be much lower than 70 %, indicating that the strain represents a separate genomic species within the genus Burkholderia. Strain HU2-65W(T) was also differentiated from other species of the genus by physiological and biochemical characteristics. Consequently, strain HU2-65W(T) is considered to represent a single, novel species of the genus Burkholderia, for which the name Burkholderia sediminicola sp. nov. is proposed, with the type strain HU2-65W(T) (=KCTC 22086(T) =LMG 24238(T)).

Unique electronic band structures of hydrogen-terminated [Formula: see text] silicon nanowires

Band structure mutation from an indirect to a direct gap is a well-known character of small hydrogen-terminated [Formula: see text] and [Formula: see text] silicon nanowires (SiNWs), and suggests the possible emission of silicon. In contrast, we show that hydrogen-terminated [Formula: see text] SiNWs consistently present indirect band gaps even at an extremely small size, according to our calculations using density functional theory. Interestingly, the band gap of [Formula: see text] SiNWs shows a quasi-direct feature as the wire size increases, suggesting the possibility of using medium SiNWs in optoelectronic devices. This result also indicates that the electronic structures of SiNWs are strongly orientation dependent.

Bacillus pocheonensis sp. nov., a moderately halotolerant, aerobic bacterium isolated from soil of a ginseng field

A Gram-positive, non-motile, endospore-forming bacterial strain, designated Gsoil 420T, was isolated from soil of a ginseng field in Pocheon Province, South Korea, and was characterized, using a polyphasic approach, in order to determine its taxonomic position. The novel isolate consisted of strictly aerobic, rod-shaped cells and was able to grow in medium supplemented with up to 12% NaCl at 25 degrees C and pH 6.5-7.0. Comparative 16S rRNA gene sequence analysis showed that strain Gsoil 420T fell within the radiation of the cluster comprising Bacillus species and formed a coherent cluster with Bacillus niacini (16S rRNA gene sequence similarity, 98.6%), Bacillus bataviensis (98.6%), Bacillus soli (98.3%), Bacillus drentensis (98.0%), Bacillus novalis (98.0%), Bacillus vireti (97.9%), Bacillus foraminis (97.6%), Bacillus fumarioli (97.4%) and Bacillus jeotgali (97.0%). The levels of 16S rRNA gene sequence similarity with respect to other Bacillus species with validly published names were less than 96.8%. Strain Gsoil 420T had a genomic DNA G+C content of 44.9 mol% and the predominant respiratory quinone was MK-7. The major fatty acids were anteiso-C15:0 (33.9%), iso-C15:0 (24.5%) and iso-C14:0 (19.9%). These chemotaxonomic results supported the affiliation of strain Gsoil 420T to the genus Bacillus. However, low DNA-DNA relatedness values and distinguishing phenotypic characteristics allowed genotypic and phenotypic differentiation of strain Gsoil 420T from recognized Bacillus species. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil 420T represents a novel species of the genus Bacillus, for which the name Bacillus pocheonensis sp. nov. is proposed. The type strain is Gsoil 420T (=KCTC 13943T=DSM 18135T).

Kaistia granuli sp. nov., isolated from anaerobic granules in an upflow anaerobic sludge blanket reactor

A Gram-negative, chemo-organotrophic, non-motile, non-spore-forming, rod-shaped bacterium (designated strain Ko04(T)) was isolated from anaerobic granules in an upflow anaerobic sludge blanket reactor, and was investigated using a polyphasic taxonomic approach. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Ko04(T) belongs to the order Rhizobiales in the Alphaproteobacteria. Comparative 16S rRNA gene sequence analysis showed that strain Ko04(T) was most closely related to Kaistia adipata (97.5 %) and that sequence similarities with other species of Rhizobiales with validly published names were less than 92.5 %. The predominant ubiquinone was Q-10 and the major fatty acids were C(18 : 1)omega7c/omega9t/omega12t, C(19 : 0 )cyclo omega8c and C(18 : 0). The G+C content of the genomic DNA of strain Ko04(T) was 67.8 mol%. The level of DNA-DNA relatedness with K. adipata Chj404(T) was 15 %. The results of the genotypic analyses in combination with chemotaxonomic and physiological data demonstrated that strain Ko04(T) represents a novel species within the genus Kaistia, for which the name Kaistia granuli sp. nov. is proposed. The type strain is Ko04(T) (=KCTC 12575(T)=LMG 23410(T)).

Role of low-dose, noncontrast computed tomography from integrated positron emission tomography/computed tomography in evaluating incidental 2-deoxy-2-[F-18]fluoro-D-glucose-avid colon lesions

PURPOSE

To assess the contribution of concurrent low-dose, noncontrast CT in the assessment of the malignant potential of incidental focal 2-deoxy-2-[F-18]fluoro-D-glucose (FDG)-avid colonic lesions on positron emission tomography/computed tomography (PET/CT).

PROCEDURES

Routine FDG-PET/CT scans were reviewed for identification of focal FDG-avid colon lesions, and the CT component was independently reviewed for an anatomical lesion and malignant potential based on CT criteria. Clinical, endoscopic, and histopathology follow-up was obtained.

RESULTS

A total of 85/2,916 (3%) oncology FDG-PET/CT scans had incidental focal colon lesions. Clinical and/or endoscopic follow-up was available in 83/85 (98%) patients. Focal, corresponding CT lesions were found in 44/83 (53%) patients, but features of malignancy were not assessable. Of the 44 patients with a final diagnosis, 32/44 (73%) were FDG-PET/CT true positives; 5/44 (11%) were false positives; and 7/44 (16%) had inconclusive FDG-PET/CT findings.

CONCLUSIONS

Concurrent low-dose, noncontrast CT improves localization, but does not provide independent information on the malignant potential of incidental focal colonic activity on FDG-PET/CT.

The expanding role of PET technology in the management of patients with colorectal cancer

The therapeutic options and subsequent survival of colorectal cancer (CRC) patients has increased substantially over recent years. While surgical excision of the primary cancer results in cure of approximately 50% of patients, recurrence and metastatic disease still remains a significant cause of death. Although resection of liver or lung metastases can result in cure, relapse rates remain high, indicating that patient selection needs improvement. Positron emission tomography (PET) technology has a great deal to offer with respect to CRC management, particularly in the setting of patient selection for metastasectomy and in the evaluation of possible recurrent disease, however it has not yet become a routine part of the management of all CRC patients. This review article aims to discuss the current and future implications of PET technology in the optimal management of CRC patients throughout their care pathway.

In vitro evaluation of fibrin mat and Tegaderm wound dressing for the delivery of keratinocytes--implications of their use to treat burns

The effectiveness of fibrin mat and Tegaderm delivery systems to maintain clonogenic keratinocytes in culture were evaluated using in vitro methods. A fibrin mat was found to provide a culture environment that is conducive for the proliferation of keratinocytes and supporting their ability to form colonies of good growth potential in vitro. This confirms that the fibrin mat is a good delivery system for cultured epithelial autograft (CEA). In our unit, fibrin-CEA is limited only for the treatment of severe burns due to the high cost of fibrin glue. However, this substrate is able to maintain the regenerative properties of the CEA which is crucial for the treatment of extensive and full thickness burns. Tegaderm, a cost-effective polyurethane wound dressing is able to support keratinocyte cell growth but at a slower rate and with fewer colonies formed compared to the fibrin system. This suggests that Tegaderm can be an alternative approach of delivering autologous cells, limited to treat chronic wounds and less extensive burns. The use of simple and relatively inexpensive bench techniques can potentially serve as a quality control to check for keratinocytes cultured and delivered to every patient in the clinical setting.

Segetibacter koreensis gen. nov., sp. nov., a novel member of the phylum Bacteroidetes, isolated from the soil of a ginseng field in South Korea

A novel strain, designated Gsoil 664(T), isolated from the soil of a ginseng field in South Korea, was characterized by a polyphasic approach to clarify its taxonomic position. The isolate was Gram-negative, strictly aerobic, heterotrophic, non-motile, non-spore-forming and possessed rod-shaped cells. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel isolate formed a cluster with several uncultured bacterial clones and with the established genera Terrimonas, Niastella and Chitinophaga in the phylum Bacteroidetes. However, the isolate was clearly separated from these genera: the gene sequence similarities with respect to the type strains of recognized species from closely related genera ranged from 86.7 to 90.7 %. The G+C content of the genomic DNA was 40.4 mol%. The predominant isoprenoid quinone was MK-7. The major fatty acids were iso-C(15 : 0), iso-C(17 : 0) 3-OH, iso-C(15 : 1) and C(16 : 1) omega 5c. The results of physiological and biochemical tests allowed the genotypic and phenotypic differentiation of strain Gsoil 664(T) from recognized species of related genera. On the basis of the polyphasic evidence, Gsoil 664(T) represents a novel genus and species, for which the name Segetibacter koreensis gen. nov., sp. nov. is proposed. The type strain of S. koreensis is Gsoil 664(T) (=KCTC 12655(T)=DSM 18137(T)).

Microlunatus ginsengisoli sp. nov., isolated from soil of a ginseng field

A Gram-positive, aerobic, coccus-shaped, non-endospore-forming bacterium (Gsoil 633(T)) was isolated from soil from a ginseng field in Pocheon province in South Korea. The novel isolate was characterized in order to determine its taxonomic position. On the basis of 16S rRNA gene sequence similarities, strain Gsoil 633(T) was shown to belong to the family Propionibacteriaceae. The closest phylogenetic relative was Microlunatus phosphovorus DSM 19555(T), with 96.1 % sequence similarity; the sequence similarity to other members of the family was less than 95.4 %. The isolate was characterized chemotaxonomically as having ll-2,6-diaminopimelic acid in the cell-wall peptidoglycan, MK-9(H(4)) as the predominant menaquinone and anteiso-C(15 : 0), iso-C(15 : 0) and iso-C(16 : 0) as the major fatty acids. The G+C content of the genomic DNA was 69.8 mol%. The morphological and chemotaxonomic properties of the isolate were consistent with those of M. phosphovorus, but the results of physiological and biochemical tests allowed the phenotypic differentiation of strain Gsoil 633(T) from this species. Therefore, strain Gsoil 633(T) represents a novel species, for which the name Microlunatus ginsengisoli sp. nov. is proposed. The type strain is Gsoil 633(T) (=KCTC 13940(T)=DSM 17942(T)).

Aeromicrobium panaciterrae sp. nov., isolated from soil of a ginseng field in South Korea

A Gram-positive, rod-shaped, non-spore-forming and strictly aerobic bacterium (Gsoil 161(T)) was isolated from soil of a ginseng field in Pocheon Province, South Korea. The novel isolate was characterized using a polyphasic approach in order to determine its taxonomic position. On the basis of 16S rRNA gene sequence similarity, strain Gsoil 161(T) was shown to belong to the family Nocardioidaceae and was related to Aeromicrobium marinum (98.0 % similarity to the type strain), Aeromicrobium alkaliterrae (97.6 %), Aeromicrobium fastidiosum (97.0 %) and Aeromicrobium erythreum (96.7 %); the sequence similarity with other species within the family was less than 94.4 %. It was characterized chemotaxonomically as having ll-2,6-diaminopimelic acid in the cell-wall peptidoglycan, MK-9(H(4)) as the predominant menaquinone and C(16 : 0), 10-methyl C(18 : 0) (tuberculostearic acid), C(16 : 0) 2-OH, 10-methyl C(17 : 0) and 10-methyl-C(16 : 0) as the major fatty acids. The G+C content of the genomic DNA was 65.5 mol%. These chemotaxonomic properties and phenotypic characteristics support the affiliation of strain Gsoil 161(T) to the genus Aeromicrobium. Results of physiological and biochemical tests enabled strain Gsoil 161(T) to be differentiated genotypically and phenotypically from currently known Aeromicrobium species. Therefore, strain Gsoil 161(T) represents a novel species, for which the name Aeromicrobium panaciterrae sp. nov. is proposed. The type strain is strain Gsoil 161(T) (=KCTC 19131(T)=DSM 17939(T)=CCUG 52476(T)).

Condensation of silicon nanowires from silicon monoxide by thermal evaporation — An X-ray absorption spectroscopy investigation

We report a Si K-edge X-ray absorption fine structures (XAFS) study of silicon monoxide (SiO), the starting material for silicon nanowire preparation, its silicon nanowires, and the residue after the preparation of the starting material. The silicon nanowires were condensed onto three different substrates, (i) the wall of the furnace quartz tube, (ii) a porous silicon substrate, and (iii) a Si(100) silicon wafer. It was found that the Si K-edge XAFS of SiO exhibits identifiable spectral features characteristic of Si in 0 and 4 oxidation states as well as in intermediate oxidation states, while the SiO residue primarily shows features of Si(0) and Si(4). The XAFS suggest that SiO is not exactly a simple mixture of Si and SiO2. The silicon nanowires produced by the process exhibit morphology and luminescence property variations that depend on the nature of the substrate. X-ray excited optical luminescence (XEOL) at the O K-edge suggests an efficient energy transfer to the optical decay channel. The results and their implications are discussed.Key words: silicon nanowires, thermal evaporation, silicon monoxide, X-ray absorption fine structures, X-ray excited optical luminescence.

Development of genu varum in achondroplasia: relation to fibular overgrowth

Genu varum in the achondroplastic patient has a complex and multifactorial aetiology. There is little mention in the literature of the role of fibular overgrowth. Using the ratio of fibular to tibial length as a measurement of possible fibular overgrowth, we have related it to the development of genu varum. Full-length standing anteroposterior radiographs of 53 patients with achondroplasia were analysed. There were 30 skeletally-immature and 23 skeletally-mature patients. Regression analysis was performed in order to determine if there was a causal relationship between fibular overgrowth and the various indices of alignment of the lower limb. Analysis showed that the fibular to tibial length ratio had a significant correlation with the medial proximal tibial angle and the mechanical axial deviation in the skeletally-immature group. We conclude that there is a significant relationship between fibular overgrowth and the development of genu varum in the skeletally-immature achondroplastic patient.

Methylibium fulvum sp. nov., a member of the Betaproteobacteria isolated from ginseng field soil, and emended description of the genus Methylibium

Two bacterial strains, designated Gsoil 322T and Gsoil 328, were isolated from soil of a ginseng field in Pocheon province (Republic of Korea). The strains were Gram-negative, motile, aerobic rods that showed nearly identical physiological profiles and similar chemotaxonomic profiles. The two strains were oxidase-positive but catalase-negative, reduced nitrate to nitrite and had fatty acid profiles in which C16 : 0, C17 : 0 cyclo and C16 : 1 ω7c/iso-C15 : 0 2-OH were predominant. The DNA G+C contents of Gsoil 322T and Gsoil 328 were 66.6 and 66.7 mol%, respectively. Q-8 was observed as the major quinone. Comparative 16S rRNA gene sequence analysis showed that strain Gsoil 322T belongs to the class Betaproteobacteria and was most closely related to Methylibium petroleiphilum ATCC BAA-1232T (97.5 % sequence similarity). On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil 322T (=KCTC 12591T =LMG 23394T) was classified in the genus Methylibium as the type strain of a novel species, for which the name Methylibium fulvum sp. nov. is proposed.

Nocardioides panacihumi sp. nov., isolated from soil of a ginseng field

A novel bacterial strain designated Gsoil 616T was isolated from a soil sample of a ginseng field in Pocheon province (South Korea) and was characterized taxonomically by using a polyphasic approach. The isolate was Gram-positive, strictly aerobic, non-motile, non-spore-forming and rod- or coccoid-shaped. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the genus Nocardioides in the family Nocardioidaceae but was clearly separated from established species of this genus. The 16S rRNA gene sequence similarities between strain Gsoil 616T and the type strains of Nocardioides species with validly published names ranged from 91.8 to 96.1 %. The G+C content of the genomic DNA was 73 mol%. Phenotypic and chemotaxonomic data [major menaquinone MK-8(H4) and major fatty acid iso-C16 : 0] supported the affiliation of strain Gsoil 616T to the genus Nocardioides. However, the results of physiological and biochemical tests allowed phenotypic differentiation of the isolate from other Nocardioides species. Therefore, strain Gsoil 616T represented a novel species within the genus Nocardioides, for which the name Nocardioides panacihumi sp. nov. is proposed. The type strain is Gsoil 616T (=KCTC 19187T =DSM 18660T).

Aspromonas composti gen. nov., sp. nov., a novel member of the family Xanthomonadaceae

Two novel bacteria, strains TR7-09T and P2-12-1, were isolated from samples of compost and river sediment, respectively. The strains comprised Gram-negative, motile, non-spore-forming rods, produced creamy white colonies on R2A agar, contained Q-8 as the predominant ubiquinone, contained iso-15 : 0, iso-17 : 0ω9c and iso-11 : 0 3-OH as the major fatty acids, and had polar lipid profiles consisting of phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol and an unknown phospholipid. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strains were most closely related to Thermomonas haemolytica DSM 13605T, Silanimonas lenta KCTC 12236T and Xanthomonas campestris LMG 568T (with 92.5, 92.0 and 92.0 % sequence similarity, respectively) and formed a separate lineage within the family Xanthomonadaceae. The combined genotypic and phenotypic data supported the conclusion that the strains represent a novel genus and species, for which the name Aspromonas composti gen. nov., sp. nov. is proposed. The type strain is TR7-09T (=KCTC 12666T=DSM 18010T).

Rhodanobacter thiooxydans sp. nov., isolated from a biofilm on sulfur particles used in an autotrophic denitrification process

A novel thiosulfate-oxidizing bacterium, designated strain LCS2T, was isolated from a biofilm on sulfur particles used in an autotrophic denitrification process. The strain was found to comprise Gram-negative, non-motile, non-spore-forming rods that produced yellow-pigmented colonies on R2A agar. The strain contained Q-8 as the major ubiquinone and 17 : 1 iso ω9c, 15 : 0 iso and 17 : 0 iso as the major fatty acids. The G+C content of the genomic DNA was 64.6 mol%. The 16S rRNA gene sequence of strain LCS2T was found to be most similar to that of Rhodanobacter fulvus IAM 15025T (97.4 % similarity). The results of DNA–DNA hybridization and phenotypic analysis showed that strain LCS2T can be distinguished from all known Rhodanobacter species and therefore represents a novel species of the genus, for which the name Rhodanobacter thiooxydans sp. nov. is proposed. The type strain is LCS2T (=DSM 18863T =KCTC 12771T).

Sphingomonas kaistensis sp. nov., a novel alphaproteobacterium containing pufLM genes

Three Gram-negative, non-motile, non-spore-forming short rods (strains PB56T, PB180, PB229) were isolated from soil in South Korea. Cells were orange–red in colour. Strains PB180 and PB229 contained small amounts of bacteriochlorophyll a, which was not detected in strain PB56T. However, all three isolates contained the genes for the photosynthetic type II reaction centre, pufLM. They contained Q-10 as the dominant quinone and C18 : 1 as the dominant fatty acid. The highest 16S rRNA gene sequence similarities were found to Sphingomonas oligophenolica JCM 12082T (95.8 %), Sphingomonas koreensis KCTC 2882T (95.1 %), Sphingomonas mali IFO 15500T (95.1 %), Sphingomonas faeni DSM 14747T (94.8 %), Sphingomonas pruni IFO 15498T (94.7 %) and Sphingomonas aquatilis KCTC 2881T (94.6 %), as well as to Sphingosinicella microcystinivorans Y2T and Sphingosinicella xenopeptidilytica 3-2W4T (95.0–95.2 %). Phylogenetic analyses supported the assignment of strains PB56T, PB180, PB229 to the genus Sphingomonas. The novel isolates differ from all established species of the genus Sphingomonas by their higher G+C content and the absence of straight-chain 2-hydroxy fatty acids. Based on the phylogenetic distances from species with validly published names and their phenotypic properties, the strains constitute a separate species, for which the name Sphingomonas kaistensis sp. nov. is proposed. The type strain is PB56T (=KCTC 12334T=DSM 16846T).

Chitinophaga ginsengisegetis sp. nov. and Chitinophaga ginsengisoli sp. nov., isolated from soil of a ginseng field in South Korea

Two novel strains belonging to the phylum Bacteroidetes [formerly the Cytophaga–Flexibacter–Bacteroides (CFB) group], designated Gsoil 040T and Gsoil 052T, were isolated from the soil of a ginseng field in Pocheon province, South Korea. A polyphasic approach was used to characterize the taxonomic position of the novel strains. Both strains were Gram-negative, aerobic, non-motile, non-spore-forming and rod-shaped. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel isolates belong to the genus Chitinophaga but are clearly separated from the recognized species of this genus; gene sequence similarities between the novel isolates and type strains of recognized species ranged from 91.2 to 96.5 %. One exception was found; strain Gsoil 052T and the type strain of Chitinophaga filiformis had a gene sequence similarity of 99.6 % but had a DNA–DNA relatedness value of 38 %. Phenotypic and chemotaxonomic data (major menaquinone, MK-7; major fatty acids, iso-C15 : 0 and C16 : 1 ω5c; major hydroxy fatty acid, iso-C17 : 0 3-OH and major polyamine, homospermidine) supported the affiliation of both strains Gsoil 040T and Gsoil 052T to the genus Chitinophaga. The results of physiological and biochemical tests enabled the genotypic and phenotypic differentiation of the novel strains from the other recognized species of the genus Chitinophaga. Therefore, it is suggested that the new isolates represent two novel species, for which the names Chitinophaga ginsengisegetis sp. nov. [type strain Gsoil 040T (=KCTC 12654T=DSM 18108T)] and Chitinophaga ginsengisoli sp. nov. [type strain Gsoil 052T (=KCTC 12592T=DSM 18017T)] are proposed.

Cellulomonas composti sp. nov., a cellulolytic bacterium isolated from cattle farm compost

A bacterial strain, TR7-06T, which has cellulase and β-glucosidase activities, was isolated from compost at a cattle farm near Daejeon, Republic of Korea. It was a Gram-positive, aerobic or facultatively anaerobic, non-motile, rod-shaped bacterium. Phylogenetic analysis based on 16S rRNA gene sequences showed that this strain belongs to the genus Cellulomonas, with highest sequence similarity to Cellulomonas uda DSM 20107T (98.5 %). Cell wall analysis revealed the presence of type A4β, l-orn–d-Glu peptidoglycan. The cell-wall sugars detected were mannose and glucose. The predominant menaquinone was MK-9(H4); MK-8(H4) was detected in smaller quantities. The major fatty acids were anteiso-C15 : 0, C16 : 0, C14 : 0 and C18 : 0. The polar lipids detected were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The results of DNA–DNA hybridization and physiological and biochemical tests clearly demonstrated that TR7-06T represents a novel species. The combined genotypic and phenotypic data show that strain TR7-06T (=KCTC 19030T=NBRC 100758T) merits description as the type strain of a novel Cellulomonas species, Cellulomonas composti sp. nov.

Salinicoccus jeotgali sp. nov., isolated from jeotgal, a traditional Korean fermented seafood

A novel, moderately halophilic, Gram-positive coccus, designated strain S2R53-5(T), was isolated from jeotgal, a traditional Korean fermented seafood. The organism was strictly aerobic, non-motile, non-sporulating and catalase- and oxidase-positive. Strain S2R53-5(T) grew in the presence of 0.5-15 % (w/v) NaCl and at pH 6.5-11.0, with optimum growth at 5 % (w/v) NaCl and pH 7.0. The temperature range for growth was 20.0-30.0 degrees C, with an optimum temperature of 30 degrees C. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain S2R53-5(T) belongs to the family Staphylococcaceae and was most closely related to Salinicoccus roseus DSM 5351(T) (96.8 % gene sequence similarity), Salinicoccus hispanicus DSM 5352(T) (96.1 %), Salinicoccus alkaliphilus T8(T) (95.2 %) and Jeotgalicoccus halotolerans YKJ-101(T) (95.1 %). The genomic DNA G+C content was 47.0 mol%, which is in the range of 46-51 mol% that is characteristic for the genus Salinicoccus. Levels of DNA-DNA relatedness between strain S2R53-5(T) and S. roseus DSM 5351(T), S. hispanicus DSM 5352(T) and S. alkaliphilus KCTC 13928(T) were 32.2, 15.4 and 4.6 %, respectively. Chemotaxonomic data (major menaquinone, MK-6; major fatty acids, iso-C(15 : 0) and anteiso-C(15 : 0); cell-wall murein type, Lys and Gly) and 16S rRNA gene sequence analysis supported the affiliation of strain S2R53-5(T) with the genus Salinicoccus. The combined evidence from the low DNA-DNA relatedness, physiological, biochemical and other genotypic data indicate that strain S2R53-5(T) clearly represents a novel species of the genus Salinicoccus, for which the name Salinicoccus jeotgali sp. nov. is proposed. The type strain is S2R53-5(T) (=KCTC 13030(T)=LMG 23640(T)).

Methylobacterium jeotgali sp. nov., a non-pigmented, facultatively methylotrophic bacterium isolated from jeotgal, a traditional Korean fermented seafood

A novel facultatively methylotrophic, Gram-negative, rod-shaped bacterium, designated strain S2R03-9(T), was isolated from jeotgal, a traditional Korean fermented seafood. The organism was strictly aerobic, motile by means of a single polar flagellum, non-sporulating and catalase- and oxidase-positive. Strain S2R03-9(T) grew in the presence of 0-1 % (w/v) NaCl and at pH 6.0-10.0, with optimum growth in the absence of NaCl and at pH 7.0. It grew at temperatures in the range 20.0-30.0 degrees C, with optimum growth at 30 degrees C. Colonies grown on R2A medium were non-pigmented, opaque and creamy white. Phylogenetic analysis based on 16S rRNA gene sequences indicated that it was most closely related to Methylobacterium organophilum JCM 2833(T) (96.6 % similarity) and the phylogenetic similarities to all other Methylobacterium species with validly published names were less than 95.0 %. The DNA G+C content was 64.9 mol%. The phylogenetic analysis, the phenotypic assessment and the chemotaxonomic data (major ubiquinone, Q-10; major fatty acids, C(18 : 1) and C(18 : 0)) showed that S2R03-9(T) represents a novel species within the genus Methylobacterium in the class Alphaproteobacteria, for which the name Methylobacterium jeotgali sp. nov. is proposed. The type strain is S2R03-9(T) (=KCTC 12671(T)=LMG 23639(T)).