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The pairing of 1,3-di-tert-butylimidazol-2-ylidene (NHCtBu) and methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide) (MAD) acted as an interacting Lewis pair (ILP) for anionic polymerization of several acrylates.

The relationship between the primary structures of polymers and their properties has long been recognized as an important research subject for polymer chemists. Advanced chemical procedures allowing precise control of the structure also enable us to examine the topological effects on polymer properties. Cyclic polymers possess unique characteristics due to the absence of polymer termini, showing different bulk and solution properties from their corresponding linear counterparts, i.e., smaller hydrodynamic volume and radius of gyration (Rg) [1], lower intrinsic viscosity [2], high critical solution temperature [2], accelerated rate of crystallization [3], and high refractive indices [4]. To make progress in this research field, innovative synthetic procedures are essential. The synthetic strategy for cyclic polymers has two typical pathways: the ring closure of functional linear polymers and ring expansion polymerization using cyclic monomers, an initiator, or a catalyst. This review describes the recent synthetic evolution of cyclic polymers, focusing on our new strategy: ring closing without highly dilute conditions. Relationship between the primary structures and their properties is recognized as an important research subject for polymer chemists. To make progress in this academic field, innovative synthetic procedures of cyclic polymers are essential. The synthetic strategy has two typical pathways: one is the ring closure of functional linear polymers and the other is ring expansion polymerization using cyclic monomers, an initiator, or a catalyst. This focus review deals with the recent synthetic evolution of cyclic polymers, focusing on our new strategy: ring closing without highly dilute conditions.

A 253 J with 26 ns at 0.2 Hz laser performance was demonstrated using a LD pumped cryogenically cooled Yb:YAG ceramics laser amplifier. A high energy storage of 344 J was achieved with a stored energy density of 0.58 J/cm3 using a 1 kJ output multidirectional-pumping system. High energy-extraction efficiency of 56.5% was achieved with high energy fluence of 4.63 J /cm2. To the best of our knowledge, this is the highest output energy obtained with a repetitive nanosecond pulse by LD pumped solid-state laser. This paper presented a design of 1 kJ amplifier based on experimentally proven numerical data.

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

The N-heterocyclic carbene 1,3-di-tert-butylimidazol-2-ylidene (NHCtBu) and its 1:1 adduct with methyl sorbate (MS) were found to initiate anionic polymerization of N-substituted maleimides (RMIs) in organic solvents at −20 °C to afford linear and cyclic poly(RMI)s, respectively. Quantitative monomer consumption was observed when a bulky aluminum Lewis acid, such as methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide) (MAD), was used as an additive. In the presence of the NHCtBu:MS adduct as an initiator, monomer consumption was followed by ring closure without the need for highly diluted conditions to give cyclic poly(RMI)s containing α-terminal MS units, which exhibited an Mn of 3.4 × 103–6.2 × 103 and a broad polydispersity index (Mw/Mn = 2.43–2.65). Dilution was not required due to the presence of an α-terminal NHCtBu group, which acted as a counter cation for the propagating center during polymerization. The broad molecular weight distributions of the obtained polymers were ascribed to a chain transfer upon abstraction of the α-carbonyl proton of the RMIs, particularly to the neighboring NHCtBu cation unit. 1H NMR and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass analyses indicated that the proton transfer of the acidic proton was induced by the propagating anion. The topologies of the linear and cyclic poly(RMI)s were directly observed by transmission electron microscopy (TEM). Direct Observation of Cyclic Poly(N-substituted maleimide)s with Broad Size Distributions Synthesized by Anionic Polymerization using an N-Heterocyclic Carbene and Successive Ring Closure Without High Dilutions.

Two bacterial strains, isolates AC10T and AC20, which were reported in a previous study on the diversity of acetic acid bacteria in Thailand, were subjected to a taxonomic study. The phylogenetic analysis based on the 16S rRNA gene sequences showed that the two isolates were located closely to the type strains of Gluconobacter oxydans and Gluconobacter roseus . However, the two isolates formed a separate cluster from the type strains of the two species. The genomic DNA of isolate AC10T was sequenced. The assembled genomes of the isolate were analysed for average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH). The results showed that the highest ANI and dDDH values between isolate AC10T and G. oxydans DSM 3503T were 91.15 and 68.2 %, which are lower than the suggested values for species delineation. The genome-based tree was reconstructed and the phylogenetic lineage based on genome sequences showed that the lineage of isolate AC10T was distinct from G. oxydans DSM 3503T and its related species. The two isolates were distinguished from G. oxydans and their relatives by their phenotypic characteristics and MALDI-TOF profiles. Therefore, the two isolates, AC10T (=BCC 15749T=TBRC 11329T=NBRC 103576T) and AC20 (=BCC 15759=TBRC 11330=NBRC 103579), can be assigned to an independent species within the genus Gluconobacter , and the name Gluconobacter aidae sp. nov. is proposed for the two isolates.

Bacterial strain PAGU 2197T, which was isolated from soil collected from the bottom of a pond in Japan, is characterized in this study. Cells of strain PAGU 2197T were aerobic, Gram-negative, short rod-shaped, non-motile, flexirubin-producing, oxidase-positive, catalase-positive and lecithinase-negative. A phylogenetic study based on 16S rRNA gene sequences and multilocus sequence analysis (gyrB, rpoB and rpoD) indicated that strain PAGU 2197T belongs to the genus Chryseobacterium and is a member of an independent lineage including Chryseobacterium tructae CCUG 60111T (sequence similarity, 95.9 %), Chryseobacterium lactis CCUG 60566T (93.4 %) and Chryseobacterium viscerum CCUG 60103T (91.6 %). The average nucleotide identity values were 80.83–85.04 %. Because average nucleotide identity values of 95–96 % exceed the 70 % DNA–DNA hybridization cutoff value for species discrimination, strain PAGU 2197T represents a novel species in the genus Chryseobacterium . The genome of strain PAGU 2197T was 4 967 738 bp with a G+C content of 35.5 mol%. The sole respiratory quinone of strain PAGU 2197T was MK-6; the major cellular fatty acids were iso-C15 : 0, iso-C17 : 0 3OH, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and summed feature 9 (iso-C17 : 1 ω9c and/or C16 : 0 10-methyl); and the major polar lipids were phosphoglycolipids and phosphatidylethanolamine. These results indicate that strain PAGU 2197T should be classified as representing a novel species in the genus Chryseobacterium , for which the name Chryseobacterium lecithinasegens sp. nov. is proposed, with strain PAGU 2197T (=NBRC 114264T=CCUG 75150T) as the type strain.

Two bacterial strains, designated as isolates VTH-Ai14T and VTH-Ai15, that have plant growth-promoting ability were isolated during the study on acetic acid bacteria diversity in Vietnam. The phylogenetic analysis based on 16S rRNA gene sequences showed that the two isolates were located closely to Acetobacter nitrogenifigens RG1T but formed an independent cluster. The phylogenetic analysis based on 16S rRNA gene and three housekeeping genes’ (dnaK, groEL, and rpoB) sequences were analyzed. The genomic DNA of the two isolates, VTH-Ai14T and VTH-Ai15, Acetobacter nitrogenifigens RG1T, the closest phylogenetic species, and Acetobacter aceti NBRC 14818T were hybridized and calculated the %similarity. Then, phenotypic and chemotaxonomic characteristics were determined for species’ description using the conventional method. The 16S rRNA gene and concatenated of the three housekeeping genes phylogenetic analysis suggests that the two isolates were constituted in a species separated from Acetobacter nitrogenifigens, Acetobacter aceti, and Acetobacter sicerae. The two isolates VTH-Ai14T and VTH-Ai15 showed 99.65% and 98.65% similarity of 16S rRNA gene when compared with Acetobacter nitrogenifigens and Acetobacter aceti and they were so different from Acetobacter nitrogenifigens RG1T with 56.99 ± 3.6 and 68.15 ± 1.8% in DNA-DNA hybridization, when isolates VTH-Ai14T and VTH-Ai15 were respectively labeled. Moreover, the two isolates were phenotypically distinguished from Acetobacter nitrogenifigens in growth in the presence of 0.35% acetic acid (v/v), on nitrogen-free LGI medium and D-mannitol, and in no ability to solubilize phosphate. Therefore, the two isolates, VTH-Ai14T(= VTCC 910031T= BCC 67843T= TBRC 11175T= NRIC 0977T) and VTH-Ai15 (= VTCC 910032 = BCC 67844 = TBRC 11176 = NRIC 0978), can be assigned to an independent species within the genus Acetobacter, and the name of Acetobacter sacchari sp. nov. is proposed for the two isolates.

Considering the issues of shortage of medical resources and the invasiveness and infection risk involved in the collection of nasopharyngeal swab specimens, there is a need for an effective alternative test specimen for SARS-CoV-2 RNA detection. Here, we investigated suitability of saliva as a non-invasively obtained specimen for molecular detection of SARS-CoV-2 RNA in Japanese patients with COVID-19. In total, 28 paired clinical specimens of saliva and nasopharyngeal swabs were collected from 12 patients at various time points after symptom onset. Each specimen was assayed using reverse transcription real-time polymerase chain reaction (rRT-PCR) on the BD MAX open system using primers and probes targeting the N-gene. The saliva and nasopharyngeal swab specimens showed 19 and 15 positive results, respectively. No invalid (PCR inhibition) result was observed for any specimen. The qualitative results of each specimen obtained in the period immediately after symptom onset were similar. Three convalescent patients presented saliva-positive results, whereas their nasopharyngeal swabs were negative at four different time points, suggesting that saliva may be superior to nasopharyngeal swabs in terms of obtaining stable assay result of SARS-CoV-2. In conclusion, our results suggest that saliva can potentially serve as an alternative to nasopharyngeal swabs as a specimen for SARS-CoV-2 rRT-PCR. As saliva can be collected by patients themselves, it may be an effective way to overcome the shortage of personal protective equipment and specimen sampling tools.

Two Gram-staining-negative, strictly aerobic, rod-shaped bacteria, designated strains AVA-1T and AVA-2, were isolated from the root of Aloe vera (L.) Brum.f. derived from Chachoengsao Province, Thailand. The strains contained cytochrome oxidase and catalase activities. They grew in 4 % (w/v) NaCl, at a pH range of 6.0–9.0 (optimally at pH 7) and at 20–42 °C (optimally at 30–37 °C). The major isoprenoid quinone was ubiquinone with eight isoprene units (Q-8). The major fatty acids were C16 : 0 and C17 : 0 cyclo. On the basis of 16S rRNA gene sequence analysis, the strains represent a species belonging to the genus Achromobacter and are closely related to Achromobacter xylosoxidans NBRC 15126T (98.80 %), Achromobacter insolitus LMG 6003T (98.64 %), Achromobacter aminicus LMG 26690T (98.59 %), Achromobacter pulmonis LMG 26696T (98.58 %) and Achromobacter insuavis LMG 26845T (98.58 %). The DNA G+C content of strain AVA-1T was 66.5 mol%. The novel strains had low DNA–DNA relatedness values with related type strains. On the basis of the phenotypic and genotypic data obtained, the strains clearly represent a novel species, for which the name Achromobacter aloeverae sp. nov. is proposed. The type strain is strain AVA-1T (=LMG 29108T=NBRC 111463T=PCU 352T=TISTR 2383T).

A strictly aerobic, bacteriochlorophyll (BChl) a-containing alphaproteobacterium, designated strain K6T, was isolated from seawater around an aquaculture site in the Uwa Sea in Japan. The novel strain grew optimally at 30 °C at pH 7.0–7.5 and in the presence of 2.0 % (w/v) NaCl. The nonmotile and coccoid or rod-shaped cells formed pink-pigmented colonies on agar plates containing organic compounds. Cells showed an in vivo absorption maximum at 870 nm in the near-infrared region, indicating the presence of BChl a in the light-harvesting 1 complex. The new bacterial strain was Gram-stain-negative and oxidase- and catalase-positive. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain K6T was closely related to species in the genus Litoreibacter . The closest phylogenetic relatives of strain K6T were Litoreibacter ponti GJSW-31T (98.56 % sequence similarity), Litoreibacter janthinus KMM 3842T (97.63 %) and Litoreibacter albidus KMM 3851T (96.88 %). The G+C content of the genomic DNA was 58.26 mol%. The average nucleotide identity value of strain K6T with the type strain of L. ponti was 77.16 % (SD 4.79 %). The digital DNA−DNA hybridization value of strain K6T with the type strain of L. ponti was 19.40 %. The respiratory quinone was ubiquinone-10. The major cellular fatty acids were C18 : 1 ω7c, C16 : 0 and 11-methyl C18 : 1 ω7c. The dominant polar lipids were phosphatidylcholine and phosphatidylglycerol. On the basis of the genetic and phenotypic data obtained in the present study, we propose a new species in the genus Litoreibacter : Litoreibacter roseus sp. nov., whose type strain is K6T (=DSM 110109T=NBRC 114114T). Strain K6T represents the first confirmed species that produces BChl a within the genus Litoreibacter .

A 11.5 J at 40 ns output has been obtained from a diode-pumped cryo-cooled Yb:YAG ceramics active-mirror laser amplifier system. The system consists of two amplifier heads which has four Yb:YAG ceramic disks and two pump LD modules. The Yb:YAG ceramics are cooled by conventional cryostat from rear side and are pumped by LD modules from front-side. A pump pulse is delivered to Yb:YAG ceramics coaxially with a seed pulse to reduce damage risk at a dielectric coating of Yb:YAG ceramics due to simplified coating design. To realize this system design, a LD module has been developed to keep a rectangle pattern with side length of around 37 mm among imaging depth of about 10cm at working distance of about 410 mm. As an experimental result of two pass amplification, a 11.5 J pulse energy was obtained with input energy of 1.0 J and total pump energy of 90.2 J. Then, an optical-to-optical conversion efficiency was 11.6% and an extraction efficiency was estimated to be 42%. In our knowledge, this is the highest output energy with nano second pulse duration in cryo-cooled Yb:YAG active-mirror laser amplification scheme. A repetition rate of 0.05 Hz depends on a limitation of a repetition rate of the seed pulse. A dependence of small-signal-gain on pumping repetition rate of the active-mirror laser head was experimentally evaluated. From the experimental result, we have estimated a feasible repetition rate of over 5 Hz. A 10 Hz operation will be demonstrated to reduce a thermal resistance between Yb:YAG ceramics and cryostat. Finally, this laser amplifier system is installed to a 100-J class laser system as preamplifier.

A 100 J class diode-pumped solid-state laser system has been developed as a platform for acceleration of laser processing application. A 117 J output of pulse energy has been demonstrated with the main amplifier.

A Gram-negative, rod-shaped, and non-motile bacterium, designated as AI32T, was isolated from a fruit in Surat Thani, the southern district of Thailand. Phylogenetic analyses of the 16S rRNA gene, 16S-23S rRNA gene ITS, and groEL gene sequences showed that the isolate formed a quite independent cluster located outside the clusters of Acetobacter peroxydans and Acetobacter papayae. Analysis of 16S rRNA gene sequence showed that the isolate was related to the type strains of A. peroxydans and A. papayae, respectively, with 99.4 % and 99.3 % similarities. The DNA G + C content of the isolate was 59.6 mol%. The isolate was positive in catalase test and showed no growth on ethanol in the presence of ammonium sulfate. The isolate produced only d-gluconic acid from d-glucose. The predominant fatty acid of isolate AI32T was C18:1ω7C. Based on the results obtained in physiological and biochemical tests and in genotypic differences between the isolate and the type strains of the validly named species of the genus Acetobacter, the isolate is classified as a novel species, for which the name of Acetobacter suratthanensis sp. nov. is introduced. The type strain of the species is AI32T (= BCC 26087T = NBRC 111399T).

We demonstrated 117-J laser output in a nanosecond regime with a diode-pumped Yb:YAG ceramic laser amplifier. The repetition rate was 0.05 Hz, and the pulse duration was around 40 ns. 5-J input energy was amplified by two cryogenically cooled Yb:YAG ceramic laser heads. Six Yb:YAG ceramic disks in each laser head were cooled by cryogenic helium gas with a temperature of 175 K. The output energy of the first and second laser heads was about 28 and 117 J.

In some Japanese hospitals, patients using infusion bags for parenteral nutrition containing amino acids have developed Bacillus cereus bloodstream infections. We considered that proliferation of contaminated B cereus in the bag during prolonged drip infusion might be one of the causes of infection. This study indicated that 8 h is the maximum appropriate drip infusion time for peripheral parental nutrition containing amino acids to prevent B cereus bloodstream infections.

Tanticharoenia aidae sp. nov. was introduced for two strains, designated as VTH-Ai06T and VTH-Ai07, which were isolated from the stems of sugar cane collected in Vietnam. In a phylogenetic tree based on 16S rRNA gene sequences derived from the neighbor-joining method, the two strains formed a cluster along with the type strain of Tanticharoenia sakaeratensis with a bootstrap value of 64 %. The pair-wise 16S rRNA gene sequence similarity was 98.3 % between strain VTH-Ai06T and the type strain of T. sakaeratensis. The range of DNA G+C contents was from 65.2 to 65.4 mol%. In DNA–DNA hybridization, the two strains showed low similarities to T. sakaeratensis BCC 15772T. Cellular fatty acids were of C18:1ω7c as a major. A major isoprenoid quinone was Q-10. Phenotypically, the two strains differed from the type strain of T. sakaeratensis in no production of dihydroxyacetone from glycerol. The type strain is VTH-Ai06T (= VTCC 910001T = BCC 67839T = NBRC 110637T), whose DNA G+C content was 65.4 mol%.

Flexibacter tractuosa [Lewin, 1969] was reclassified as Marivirga tractuosa . Flexibacter tractuosus NBRC 15981T was reclassified herein by using a polyphasic taxonomic approach. Cells of the strain were strictly aerobic, Gram-stain-negative, slender rods, which were motile by gliding. The major respiratory quinone was menaquinone-7 and the predominant (>5 %) cellular fatty acids were iso-C15 : 0, iso-G-C15 : 1, C16 : 1ω7c and iso-C17 : 0 3-OH. The polar lipid pattern indicated the presence of a phosphatidylethanolamine, several unidentified aminolipids, glycolipids and five unidentified polar lipids. The G+C content of the genomic DNA was 35.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain NBRC 15981T clustered with members of the genus Marivirga in the family Flammeovirgaceae of the phylum Bacteroidetes . Levels of DNA–DNA relatedness were less than 16 % between strain NBRC 15981T and the two closely related species, Marivirga sericea NBRC 15983T and Marivirga tractuosa NBRC 15989T. Strain NBRC 15981T could be differentiated from these type strains in the genus Marivirga based on the polar lipid pattern and the activity of α-chymotrypsin, as well as by α-glucosidase and β-glucosidase activity. On the basis of these results, NBRC 15981T is proposed as representing a novel species of the genus Marivirga , named Marivirga harenae sp. nov. The type strain is JK11T (=NBRC 15981T=NCIMB 1429T).

A 64J at 10 ns output was demonstrated by diode-pumped cryogenically cooled Yb:YAG ceramic laser amplifier. An extraction efficiency was evaluated 43.3% at stored energy of 148J with small-signal-gain of 20.4.

A compact 40kW at 10Hz output LD module has been developed for cryogenically cooled Yb:YAG ceramics active-mirror laser amplifiers for 10J at 10Hz output laser system. Pumping intensity is 2.5kW/cm2 and footprint of the LD module is 18cm × 77cm.

We have been developing a high-resolution superconducting time-of-flight mass spectrometry (TOF-MS) system, which utilizes a superconducting strip ion detector (SSID) and a single-flux-quantum (SFQ) time-to-digital converter (TDC). The SFQ TDC can measure time intervals between multiple input signals and directly convert them into binary data. In our previous study, 24-bit SFQ TDC with a 3 × 24-bit First-In First-Out (FIFO) buffer was designed and implemented using the AIST Nb standard process 2 (STP2), whose time resolution and dynamic range are 100 ps and 1.6 ms, respectively. In this study we reduce the jitter of the TDC by using two different approaches: one uses an on-chip clock generator with an on-chip low-pass filter for reducing the noise in the bias current, and the other uses a low-jitter external clock source at room temperature. We confirmed that the jitter is reduced to less than 100 ps in the latter approach.

Two Nguyenibacter vanlangensis strains TN01LGIT and VTH-AC01 isolated by an enrichment approach using nitrogen free LGI medium from Asian rice isolation sources are expected as an additional PGPB within the Acetobacteraceae family. In this study, nitrogen fixing capability of the two N. vanlangensis strains was confirmed through nitrogenase activity’s detection by acetylene reduction analysis...

New, stable, and glyoco-derivatized gold nanorods (GNRs) were prepared using developed amphiphilic block glycopolymers poly[(lactose)m-b-(pyridine)n] to engineer self-organized, densely packed glyc...

A coccoid and amorphous-shaped, non-gliding, proteorhodopsin-containing, yellow bacterium, designated strain SG-18T, was isolated from seawater in the western North Pacific Ocean near Japan. The strain was Gram-stain-negative, obligately aerobic, heterotrophic and oxidase-positive. It hydrolysed aesculin but not DNA, urea, gelatin or agar. Growth occurred in the presence of 1–5 % NaCl, with optimum growth at 2 % NaCl. The strain grew at 15–37 °C with an optimum temperature of 25–30 °C. The DNA G+C content of the genomic DNA of strain SG-18Twas 47.0 mol% (HPLC). The predominant isoprenoid quinone was MK-6, and major cellular fatty acids were iso-C15 : 1G, iso-C15 : 0, iso-C15 : 03-OH. Phylogenetic trees generated by using 16S rRNA gene sequences revealed that strain SG-18Tbelonged to the familyFlavobacteriaceaeand showed 92.7 % sequence similarity to the most closely related species,Croceitalea eckloniaeDOKDO 025T. On the basis of phenotypic and phylogenetic features, strain SG-18Tis classified as representing a novel species of a new genus within the familyFlavobacteriaceae, for which the nameAureicoccus marinusgen. nov., sp. nov. is proposed. The type strain of the type species is SG-18T( = NBRC 108814T = KCTC 23967T).

seven species are now-adays accommodated (Franke et al., 1999; Fuentes-Ramirez et al., 2001; Gillis et al., 1989; Tazato et al., 2012; Yamada and Yukphan, 2008). In the systematic and ecological studies of acetic acid bacteria, the present authors found that a certain strain isolated from the natural environment of Vietnam was located in a unique phylogenetic position, name-ly, outside of the

Two aerobic, Gram-negative, orange pigmented and irregular rod-shaped bacteria, designated S1-05 and S1-08T, were isolated from seawater from the Pacific Ocean. Phylogenetic analysis based on their 16S rRNA gene sequences revealed that the novel isolates could be affiliated with the genus Nonlabens of the family Flavobacteriaceae. The strains S1-05 and S1-08T shared 100 % pairwise sequences similarity with each other and showed less than 96.8 % similarity with the cultivated members of the genus Nonlabens. The novel isolates are phenotypically and physiologically different from strains described previously. The strains were found to be non-motile, oxidase positive, catalase positive and hydrolyzed gelatin and aesculin. The G+C contents of the DNA were determined to 41.4 and 41.7 mol% and MK-6 the predominant menaquinone. Anteiso-C15:0 and iso-C15:0 were found to be the major two cellular fatty acids. On the basis of polyphasic taxonomic studies, it was concluded that strains S1-05 and S1-08T represent a novel species within the genus Nonlabens, for which the name Nonlabens marina sp. nov. is proposed. The type strain of N. marina is S1-08T (=KCTC 23432T = NBRC 107738T).

Rubber-degrading bacteria were screened for the production of clearing zones around their colonies on latex overlay agar plates. Novel three bacteria, Streptomyces sp. strain LCIC4, Actinoplanes sp. strain OR16, and Methylibium sp. strain NS21, were isolated. To the best of our knowledge, this is the first report on the isolation of a Gram-negative rubber-degrading bacterium other than γ-proteobacteria. Gel permeation chromatography analysis revealed that these strains degraded poly(cis-1,4-isoprene) to low-molecular-weight products. The occurrence of aldehyde groups in the degradation products by NS21 was suggested by staining with Schiff's reagent and ¹H-nuclear magnetic resonance spectroscopy. The lcp gene of LCIC4, which showed 99% amino acid sequence identity with that of Streptomyces sp. strain K30, was cloned, and contained a putative twin-arginine motif at its N terminus. It is located next to oxiB, which is estimated to be responsible for oxidation of degradation intermediate of rubber in K30. Southern hybridization analysis using LCIC4 lcp probe revealed the presence of a lcp-homolog in OR16. These results suggest that the lcp-homologs are involved in rubber degradation in LCIC4 and OR16.

The genus Gluconacetobacter is divided into two groups phylogenetically, phenotypically and ecologically: the Gluconacetobacter liquefaciens group and the Gluconacetobacter xylinus group. For the latter group, the genus Komagatabacter is newly introduced, and the type species of the new genus is designated as Komagatabacter xylinus (Brown 1886) comb. nov. Twelve species of the Gluconacetobacter xylinus group are transferred to the new genus as new combinations.

A novel bacterium, designated strain OX-01T, was isolated from acidic soil, taxonomically investigated and identified as an agent that catabolizes (+)-catechin into taxifolin. Strain OX-01T is a Gram-reaction-negative, aerobic, non-sporulating, non-motile and rod-shaped bacterium. 16S rRNA gene sequence analysis identified this strain as a member of the genus Burkholderia and occupying a phylogenetic position closest to, but clearly distinct from, Burkholderia sacchari. Strain OX-01T does not have any nif genes, which are required for N2-fixation, in its genome, a feature that is similar to B. sacchari, which lacks nifH, but is distinct from the N2-fixing features of many other phylogenetically related taxa, such as Burkholderia ferrariae, B. heleia, B. mimosarum, B. nodosa, B. silvatlantica, B. tropica and B. unamae. Strain OX-01T has the following chemotaxonomic characteristics: the major ubiquinone is Q-8, the DNA G+C content is 64 mol% and the major fatty acids are C16 : 0, C17 : 0 cyclo and C18 : 1 ω7c. It also has a unique profile of carbohydrate utilization among other species of the genus Burkholderia. The strain cannot assimilate many pentoses, hexoses and oligosaccharides, whereas it can catabolize (+)-catechin and its putative aromatic derivatives, such as 4-hydroxy-3-methoxycinnamic acid, protocatechuic acid, p-hydroxybenzoic acid, trans-p-coumaric acid and vanillic acid. Based on its morphological, physiological and chemotaxonomic characteristics, together with DNA–DNA relatedness values and 16S rRNA gene sequence comparison data, we show that strain OX-O1T represents a novel species of the genus Burkholderia, for which the name Burkholderia oxyphila sp. nov. is proposed. The type strain is OX-01T (=NBRC 105797T =DSM 22550T).

The taxonomic position of three bacterial strains, Asr22-19T, NBRC 101035 and NBRC 101041, isolated from shellfish in Japan, was determined by using a polyphasic taxonomic approach. The strains were facultatively anaerobic, motile by gliding and Gram-staining-negative slender rods. Their major respiratory quinone was menaquinone-7 and their predominant cellular fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 0 3-OH, C16 : 0 3-OH, and C16 : 0. The G+C content of the genomic DNA was 42.0–42.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strains clustered with the genus Persicobacter in the family ‘Flammeovirgaceae’. DNA–DNA relatedness values were higher than 68 % among strains Asr22-19T, NBRC 101035 and NBRC 101041, and were lower than 28 % between strain Asr22-19T and Persicobacter diffluens NBRC 15940T. The three novel strains could be differentiated from Persicobacter diffluens by several phenotypic characteristics. On the basis of these results, the novel species Persicobacter psychrovividus sp. nov. (type strain Asr22-19T=NBRC 101262T=CIP 109100T) is proposed and emended descriptions are given for the genus Persicobacter and for Persicobacter diffluens.

The taxonomic positions of two bacterial strains, ir6-1T and ir6-4T, isolated from soil collected in Iriomote Island in Japan, were determined by using a polyphasic taxonomic approach. The strains were facultatively anaerobic, motile and Gram-stain-negative rods and their optimum pH for growth was pH 4.0. Their major respiratory quinone was ubiquinone-8 and the predominant cellular fatty acids were C14 : 0, C16 : 0, C16 : 1 ω7c and C18 : 1 ω7c. The G+C content of the genomic DNA of ir6-1T and ir6-4T was 59.9 and 57.5 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strains clustered with the genus Silvimonas in the class Betaproteobacteria. DNA–DNA similarities were lower than 53 % among ir6-1T, ir6-4T and Silvimonas terrae NBRC 100961T, and these strains could be differentiated from each other by several phenotypic characters. Based on these results, we propose the emendation of the genus Silvimonas and inclusion of two novel species, Silvimonas iriomotensis sp. nov. (type strain ir6-1T=NBRC 103188T =CGMCC 1.8859T =KCTC 22513T) and Silvimonas amylolytica sp. nov. (ir6-4T =NBRC 103189T =CGMCC 1.8860T =KCTC 22514T).

Sphingolipid metabolites including ceramide, sphingosine, and their phosphorylated products [sphingosine-1-phosphate (S1P) and ceramide-1-phosphate] regulate cell functions including arachidonic acid (AA) metabolism and cell death. The development of analogs of S1P may be useful for regulating these mediator-induced cellular responses. We synthesized new analogs of S1P and examined their effects on the release of AA and cell death in L929 mouse fibrosarcoma cells. Among the analogs tested, several compounds including DMB-mC11S [dimethyl (2S,3R)-2-tert-butoxycarbonylamino-3-hydroxy-3-(3’-undecyl)phenylpropyl phosphate] and DMB-mC9S [dimethyl (2S,3R)-2-tert-butoxycarbonylamino-3-hydroxy-3-(3’-nonyl)phenylpropyl phosphate] released AA within 1 h and caused cell death 6 h after treatment. The release of AA was observed in C12 cells [a L929 variant lacking a type α cytosolic phospholipase A2 (cPLA2α)] and L929-cPLAα–siRNA cells (L929 cells treated with small interference RNA for cPLA2α). Treatment with pharmacological inhibitors of secretory and Ca2+-independent PLA2s decreased the DMB-mC11S–induced release of AA. The effect of the S1P analogs tested on the release of AA was comparable to that on cell death in L929 cells, and a high correlation coefficient was observed. Two analogs lacking a butoxycarbonyl moiety [DMAc-mC11S (dimethyl (2S,3R)-2-acetamino-3-hydroxy-3-(3’-undecyl)phenylpropyl phosphate] and DMAm-mC11S [dimethyl (2S,3R)-2-amino-3-hydroxy-3-(3’-undecyl)phenylpropyl phosphate)] had inhibitory effects on the release of AA and cell toxicity induced by DMB-mC11S. Synthetic phosphorylated lipid analogs may be useful for studying PLA2 activity and its toxicity in cells.[Supplementary Fig. 1: available only at http://dx.doi.org/10.1254/jphs.08284FP] Keywords:: sphingosine-1-phosphate, ceramide-1-phosphate, synthetic analog, phospholipase A2, cell death

We analyzed perfluorinated surfactants (PFSs) in 20 river samples and 5 wastewater secondary effluent samples in Japan to reveal their occurrence and sources. Nine PFS species were determined: perfluorooctanesulfonate (PFOS), perfluorooctane sulfonamide (FOSA), perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUA), perfluorododecanoate (PFDDA), and perfluorotridecanoate (PFTDA). PFSs were detected in all rivers, revealing nationwide contamination of rivers. In particular, 11 out of 20 river samples exceeded New Jersey guidance for PFOA in drinking water (40 ng/L). PFOS, PFHpA, PFOA, and PFNA were major species in Japan. Concentrations of PFOS, PFHpA, and PFNA in rivers were strongly correlated with population density, suggesting that the chemicals were derived from urban activities. PFOA showed a significant but weak correlation. We used crotamiton, a marker of sewage effluent, for further source analysis. Concentrations of PFOS, PFHpA, and PFNAwere strongly correlated with those of crotamiton, and plots of secondary effluents fell near the regression lines of rivers, indicating that the PFOS, PFHpA, and PFNA in rivers were derived from sewage effluent. On the other hand, PFOA was found at remarkably high levels (54-192 ng/L) in seven river samples containing low levels of crotamiton, suggesting that it was derived from nonsewage point sources, as well as sewage effluent. The total fluxes of sewage-derived PFOS, PFHpA, PFOA, and PFNA from Japan were estimated to be 3.6, 2.6, 5.6, and 2.6 t/year, respectively. This is the first report to identify PFOA in several rivers, derived from nonsewage point sources, by using a marker of sewage effluent.

A polyphasic study was performed to determine the taxonomic position of strain EK05(T) isolated from a root-outgrowth of Entada koshunensis, a legume available in Okinawa, Japan. Phylogenetic analysis of the 16S rRNA gene showed that the strain belongs to the genus Bradyrhizobium. Subsequent multilocus sequence analysis with ITS, glnII, recA, gyrB, and atpD sequences revealed that the isolate represents a distinct evolutionary lineage within the genus Bradyrhizobium. DNA-DNA hybridization indicated that strain EK05(T) shares61% DNA relatedness with the type strains of all six recognized species of Bradyrhizobium, confirming that this strain is a novel species within the genus. Phylogenetic trees based on symbiotic loci, nifH and nodC, also placed strain EK05(T) clearly in a novel branch. On the basis of its phylogenetic distinctiveness, we propose Bradyrhizobium iriomotense sp. nov. for strain EK05(T). The type strain is EK05(T) (= NBRC 102520(T) = LMG 24129(T)).