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1.
Int J Syst Evol Microbiol ; 70(10): 5551-5560, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32915122

ABSTRACT

Three aerobic, Gram-stain-negative, non-motile, rod-shaped bacteria, designated as strains SHINM1T, ICHIJ1 and ICHIAU1, were isolated from surface river water (Saitama Prefecture, Japan). Phylogenetic analyses based on 16S rRNA and 40 marker gene sequences revealed that the strains formed a distinct phylogenetic lineage within the order Rhodocyclales. The three strains shared 100 % 16S rRNA gene similarity. Growth occurred at 15-30 °C and pH 6.0-9.5, but not in the presence of ≥1.0 % (w/v) NaCl. The isolates stained positive for intracellular polyphosphate granules. The major cellular fatty acids were C16 : 0, summed feature 2 (C12 : 1 aldehyde and/or iso-C16 : 1 I and/or C14 : 0 3-OH), summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The major polar lipids were phosphatidylethanolamine and an unidentified phospholipid. The predominant quinone system of strain SHINM1T was ubiquinone-8 and its DNA G+C content was 56.7 mol%. Genome sequencing of the three isolates revealed a genome size of 2.29-2.43 Mbp and average nucleotide identity by orthology values of ≥98.9 %. Based on the results of phenotypic and phylogenetic analyses, strains SHINM1T, ICHIJ1 and ICHIAU1 represent a novel species of a new genus, for which the name Fluviibacter phosphoraccumulans gen. nov., sp. nov. is proposed, within a new family, Fluviibacteraceae fam. nov. of the order Rhodocyclales. The type strain is SHINM1T (=JCM 32071T=NCIMB 15105T).


Subject(s)
Betaproteobacteria/classification , Phylogeny , Rivers/microbiology , Bacterial Typing Techniques , Base Composition , Betaproteobacteria/isolation & purification , DNA, Bacterial/genetics , Fatty Acids/chemistry , Japan , Phospholipids/chemistry , Polyphosphates/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Ubiquinone/chemistry
2.
Bull Environ Contam Toxicol ; 99(2): 203-207, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28634686

ABSTRACT

We determined the respiratory uptake and depuration kinetics of perfluorooctanesulfonate (PFOS) in Perinereis wilsoni, a polychaete sandworm used as a model species to investigate the fate of chemical pollutants in coastal environments. The sandworms were kept in gravel-packed containers, and the water levels were varied cyclically to mimic the tides. We used seawater kept at 17.1°C. A 7-day exposure period was followed by a 9-day depuration period. The dissolved PFOS concentration averaged 28 ng/L during the exposure period. Sandworm samples were collected regularly for analysis of PFOS concentrations, and a first-order-kinetics model was applied to the concentrations. The respiratory absorption efficiency of PFOS was estimated to be 11% that of oxygen, which is higher than the corresponding estimates reported for several fish species. The estimated depuration half-life of 15 days was comparable to previously reported estimates for fish and oligochaete species. The bioconcentration factor was 470.


Subject(s)
Alkanesulfonic Acids/metabolism , Fluorocarbons/metabolism , Polychaeta/metabolism , Water Pollutants, Chemical/metabolism , Alkanesulfonic Acids/analysis , Animals , Fishes , Fluorocarbons/analysis , Half-Life , Kinetics , Seawater , Water , Water Pollutants, Chemical/analysis
3.
Environ Microbiol ; 14(9): 2511-25, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22759205

ABSTRACT

The free-living, cosmopolitan, freshwater betaproteobacterial bacterioplankton genus Polynucleobacter was detected in different years in 11 lakes of varying types and a river using the size-exclusion assay method (SEAM). Of the 350 strains isolated, 228 (65.1%) were affiliated with the Polynucleobacter subclusters PnecC (30.0%) and PnecD (35.1%). Significant positive correlations between fluorescence in situ hybridization and SEAM data were observed in the relative abundance of PnecC and PnecD bacteria to Polynucleobacter communities (PnecC + PnecD). Isolates were mainly PnecC bacteria in the samples with a high specific UV absorbance at 254 nm (SUVA(254) ), and a low total hydrolysable neutral carbohydrate and amino acid (THneutralCH + THAA) content of the dissolved organic matter (DOM) fraction, which is known to be correlated with a high humic content. In contrast, the PnecD bacteria were abundant in samples with high chlorophyll a and/or THneutralCH + THAA concentrations, indicative of primary productivity. With few exceptions, differences in the relative abundance of PnecC and PnecD in each sample, determined using a high-sensitivity cultivation-based approach, were due to DOM quality. These results suggest that the major DOM component in the field, which is allochthonously or autochthonously derived, is a key factor for ecological niche separation between PnecC and PnecD subclusters.


Subject(s)
Burkholderiaceae/physiology , Fresh Water/chemistry , Fresh Water/microbiology , Water Microbiology , Chlorophyll/analysis , Ecosystem , In Situ Hybridization, Fluorescence
4.
FEMS Microbiol Ecol ; 67(1): 57-68, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19049496

ABSTRACT

Effective isolation of freshwater bacterioplankton belonging to genus Polynucleobacter from a shallow eutrophic lake and its tributary was achieved by size-selective filtration with a 0.7-mum pore filter and cultivation on R2A agar medium. Partial 16S rRNA gene analysis showed that over 80% of all the strains were highly similar to the Polynucleobacter cluster. Essential medium components for effective cultivation are pyruvate, yeast extract and peptone, whereas soluble starch and glucose are not necessary. Isolate KF001 (affiliated with Polynucleobacter subcluster D) has a strict requirement for organic acids as carbon sources, and we hypothesize that the Polynucleobacter cluster of bacteria could utilize compounds formed via photochemically dissolved organic matter (DOM) degradation for growth. Because organic acids form from solar radiation of DOM in aquatic environments, carbon sources that are typical products of DOM photochemical degradation were added to the medium. These compounds were readily utilized by KF001 in this study. Finally, we observed the stimulation of strain KF001 activity by photochemical degradation of natural lake water. Our findings suggest a carbon flow of DOM photoproducts to Polynucleobacter in the freshwater microbial loop.


Subject(s)
Burkholderiaceae , Fresh Water/microbiology , Organic Chemicals/metabolism , Plankton , Animals , Bacteriological Techniques , Burkholderiaceae/growth & development , Burkholderiaceae/isolation & purification , Culture Media , Ecosystem , Filtration , Fresh Water/chemistry , Organic Chemicals/chemistry , Photochemistry , Plankton/growth & development , Plankton/isolation & purification , Solubility
5.
FEBS Lett ; 581(27): 5207-12, 2007 Nov 13.
Article in English | MEDLINE | ID: mdl-17950728

ABSTRACT

Expression of human T-cell leukemia virus type-1 (HTLV-1) in adult T-cell leukemia (ATL) cells is known to be marginal in vivo and inducible in short-term culture. In this study, we demonstrated that withdrawal of interleukin (IL)-2 from IL-2-dependent ATL cell lines resulted in induction of HTLV-1 mRNA and protein expression, and that viral induction was associated with phosphorylation of the stress kinase p38 and its downstream CREB. Pharmacological inhibitors of the p38 pathway suppressed viral expression induced by IL-2 depletion. These results indicate that the stress-induced p38 pathway might up-regulate HTLV-1 gene expression through at least CREB activation.


Subject(s)
Human T-lymphotropic virus 1/drug effects , Human T-lymphotropic virus 1/genetics , Interleukin-2/pharmacology , p38 Mitogen-Activated Protein Kinases/metabolism , Base Sequence , Cell Line, Tumor , Cyclic AMP Response Element-Binding Protein/metabolism , DNA Primers/genetics , DNA, Viral/genetics , Gene Expression Regulation, Viral/drug effects , Genes, Viral/drug effects , Genes, gag , HTLV-I Antigens/biosynthesis , HTLV-I Antigens/genetics , Human T-lymphotropic virus 1/immunology , Human T-lymphotropic virus 1/physiology , Humans , Leukemia-Lymphoma, Adult T-Cell/genetics , Leukemia-Lymphoma, Adult T-Cell/metabolism , Leukemia-Lymphoma, Adult T-Cell/virology , MAP Kinase Signaling System/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Viral/genetics , RNA, Viral/metabolism
6.
FEBS Lett ; 580(30): 6807-12, 2006 Dec 22.
Article in English | MEDLINE | ID: mdl-17141229

ABSTRACT

Severe acute respiratory syndrome (SARS) is characterized by rapidly progressing respiratory failure resembling acute/adult respiratory distress syndrome (ARDS) associated with uncontrolled inflammatory responses. Here, we demonstrated that, among five accessory proteins of SARS coronavirus (SARS-CoV) tested, 3a/X1 and 7a/X4 were capable of activating nuclear factor kappa B (NF-kappaB) and c-Jun N-terminal kinase (JNK), and significantly enhanced interleukin 8 (IL-8) promoter activity. Furthermore, 3a/X1 and 7a/X4 expression in A549 cells enhanced production of inflammatory chemokines that were known to be up-regulated in SARS-CoV infection. Our results suggest potential involvement of 3a/X1 and 7a/X4 proteins in the pathological inflammatory responses in SARS.


Subject(s)
Chemokines/biosynthesis , NF-kappa B/metabolism , Severe acute respiratory syndrome-related coronavirus/metabolism , Viral Matrix Proteins/metabolism , Viral Proteins/metabolism , Viral Structural Proteins/metabolism , Cell Line , Enzyme Activation , Gene Expression , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , Promoter Regions, Genetic/genetics , Severe acute respiratory syndrome-related coronavirus/genetics , Viral Matrix Proteins/genetics , Viral Proteins/genetics , Viral Structural Proteins/genetics
7.
ScientificWorldJournal ; 4: 315-23, 2004 May 11.
Article in English | MEDLINE | ID: mdl-15167945

ABSTRACT

An artificial tidal flat was prepared for the mitigation tool on coastal environment. However, it is considered that most of the flat was not restored to the sufficient amenities for aquatic living things, migratory birds, etc. because none of the ecological mechanisms were understood or planned for. It is therefore investigated in this paper that historical transition factors in ecosystem structure are selected and traced with the diffusion of a public sewerage system, and with environmental factors such as water quality, sediment condition, and aquatic producers in the Yatsu Tidal Flat. As a result, it can be defined that the tidal flat, just like a lagoon, was formed artificially with reclamation and development of its circumference at the first step of transition; the water quality and sediment condition gradually became brackish water and muddy sediment conditions, interactively. The ecosystem pyramid forming orderly layers according to trophic level appeared as a high-bio-production potential in its tidal flat. In the second step, i.e., in recent years, the characteristics of water quality and sediment conditions evolved into a foreshore tidal flat, namely, conditions in the flat observed were that the progression of water included a high concentration of chloride ion as seawater and sediment conditions became sandy. Because of that, the inflowing fresh water and organic mater from the land area decreased with the improvement of the public sewerage system. The ecosystem pyramid was distorted into a chaos pyramid, with inversion of Ulva spp.


Subject(s)
Ecosystem , Seawater , Waste Management , Water Movements , Animals , Environmental Monitoring , Geologic Sediments , Humans , Nonlinear Dynamics
8.
Org Lett ; 13(5): 932-5, 2011 Mar 04.
Article in English | MEDLINE | ID: mdl-21261277

ABSTRACT

The preparation of various (R)-Sulfur-MOP ligands with aryl and alkyl substituents on sulfur, and the application of these ligands to Pd-catalyzed asymmetric allylic alkylation of indoles is reported. The sulfur substituent served as an effective stereocontrol element, and in the case of the 2-i-PrPh substituent on sulfur, the allylation products from an array of simple and substituted indoles were obtained with high enantioselectivity (up to 95% ee).

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