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1.
Antonie Van Leeuwenhoek ; 117(1): 91, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38907751

ABSTRACT

A Gram-stain-negative, facultative anaerobe, rod-shaped strain JX-1T was isolated from UASB sludge treating landfill leachate in Wuhan, China. The isolate is capable of growing under conditions of pH 6.0-11.0 (optimum, pH 7.0-8.0), temperature 4-42 â„ƒ (optimum, 20-30 â„ƒ), 0-8.0% (w/v) NaCl (optimum, 5.0%), and ammonia nitrogen concentration of 200-5000 mg/L (optimum, 500 mg/L) on LB plates. The microorganism can utilize malic acid, D-galactose, L-rhamnose, inosine, and L-glutamic acid as carbon sources, but does not reduce nitrates and nitrites. The major fatty acids are C18:1ω7c/C18:1ω6c, iso-C15:0, and anteiso-C15:0. The respiratory quinones are Q9 (91.92%) and Q8 (8.08%). Polar lipids include aminolipid, aminophospholipid, diphosphatidylglycerol, glycolipid, phosphatidylethanolamine, phosphatidylglycerol, and phospholipid. Compared with other strains, strain JX-1T and Denitrificimonas caeni HY-14T have the highest values in terms of 16S rRNA gene sequence similarity (96.79%), average nucleotide identity (ANI; 76.06%), and average amino acid identity (AAI; 78.89%). Its digital DNA-DNA hybridization (dDDH) result is 20.3%. The genome of strain JX-1T, with a size of 2.78 Mb and 46.12 mol% G + C content, lacks genes for denitrification and dissimilatory nitrate reduction to ammonium (DNRA), but contains genes for ectoine synthesis as a secondary metabolite. The results of this polyphasic study allow genotypic and phenotypic differentiation of the analysed strain from the closest related species and confirm that the strain represents a novel species within the genus Denitrificimonas, for which the name Denitrificimonas halotolerans sp. nov. is proposed with JX-1T (= MCCC 1K08958T = KCTC 8395T) as the type strain.


Subject(s)
Base Composition , Phylogeny , RNA, Ribosomal, 16S , Sewage , Sewage/microbiology , RNA, Ribosomal, 16S/genetics , China , Fatty Acids/chemistry , DNA, Bacterial/genetics , Bacterial Typing Techniques , Aeromonadaceae/genetics , Aeromonadaceae/classification , Aeromonadaceae/isolation & purification , Aeromonadaceae/metabolism , Phospholipids/analysis
2.
Article in English | MEDLINE | ID: mdl-38284383

ABSTRACT

A Gram-stain-negative, strictly aerobic and filamentous bacterial strain, designated as DQS-5T, was isolated from the activated sludge of a municipal sewage treatment plant in Shenzhen, PR China. Optimal growth was observed at 28 °C and pH 7.5. Catalase and oxidase activities were detected. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain DQS-5T was most closely related to the genera Chitinimonas and Chitinivorax (91.0-93.4 % and 92.5 % 16S rRNA gene sequence similarity, respectively) and was close to the member of the family Burkholderiaceae. The complete genome sequence of strain DQS-5T contains 5 653 844 bp and 57.3 mol% G+C. The average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values between the genome of strain DQS-5T and those of its close relatives were 75.9-77.2, 19.0-20.3 and 57.2-61.8 %, respectively. Chemotaxonomic analysis of strain DQS-5T indicated that the sole respiratory quinone was ubiquinone-8, the predominant cellular fatty acids were C16 : 0 and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), and the major polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, aminophospholipid and aminolipid. The phylogenetic, genotypic, phenotypic and chemotaxonomic data demonstrate that strain DQS-5T represents a novel species in a novel genus within the family Burkholderiaceae, for which the name Parachitinimonas caeni gen. nov., sp. nov., is proposed. Strain DQS-5T (=KCTC 92788T=CCTCC AB 2022320T) is the type and only strain of P. caeni.


Subject(s)
Burkholderiaceae , Fatty Acids , Fatty Acids/chemistry , Phospholipids/chemistry , Sewage , Phylogeny , RNA, Ribosomal, 16S/genetics , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Sequence Analysis, DNA , China
3.
Heliyon ; 9(11): e21492, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38027798

ABSTRACT

This paper examines the impact of environmental information disclosure (EID) on corporate tax avoidance. By exploiting China's EID policy as a natural experiment, we employ a difference-in-differences (DID) estimation approach to reach the following findings: (1) EID can promote corporate tax avoidance, and this result remains robust after conducting a battery of tests; (2) the research identifies two distinct channels through which EID influences corporate tax avoidance: green innovation and capital investments; and (3) the heterogeneity analysis reveals that the impact of EID on tax avoidance is notably heightened in highly polluting industries, competitive sectors, and regions in China characterized by weak tax efforts and strong government competition. Through the application of a scientific approach, we reveal novel insights into the correlation between EID and tax avoidance, thereby providing significant implications for the development of environmental regulatory policies. In conclusion, we recommend that governments employ a targeted approach to tackle tax avoidance in specific enterprises or industries. Simultaneously, governments should consider implementing subsidies and tax incentives to mitigate the underlying incentives for enterprises to engage in tax avoidance.

4.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Article in English | MEDLINE | ID: mdl-37990978

ABSTRACT

A floc-forming bacterial strain, designated HF-7T, was isolated from the activated sludge of an industrial wastewater treatment plant in Hefei, PR China. Cells of this strain were Gram-stain-positive, catalase- and oxidase-negative, facultatively anaerobic, and rod-shaped. Growth occurred at 20-42 °C (optimum, 28 °C), at pH 5.5-10.5 (optimum, pH 7.5) and with 0-8.0 % (w/v) NaCl (optimum, 1 %). The major fatty acid was anteiso-C15 : 0. The polar lipid profile contained phosphatidylglycerol, diphosphatidylglycerol and phosphatidylinositol. The DNA G+C content was 67 mol% from whole genomic sequence analysis. Based on the results of 16S rRNA gene sequence analysis, this strain should be assigned to the genus Tessaracoccus and is closely related to Tessaracoccus arenae CAU 1319T (95.87 % similarity), Tessaracoccus lapidicaptus IPBSL-7T (95.19 %) and Tessaracoccus bendigoensis Ben 106T (94.63 %) but separated from them by large distances in different phylogenetic trees. Based on whole genome analysis, the orthologous average nucleotide identity and in silico DNA-DNA hybridization values against two of the closest relatives were 75.21-76.50 % and 14.2-24.4 %, respectively. The phylogenetic, genotypic, phenotypic and chemotaxonomic data demonstrated that strain HF-7T could be distinguished from its phylogenetically related species and represents a novel species within the genus Tessaracoccus, for which the name Tessaracoccus caeni sp. nov. is proposed. The type strain is HF-7T (=KCTC 49959T=CCTCC AB 2023019T).


Subject(s)
Fatty Acids , Propionibacteriaceae , Fatty Acids/chemistry , Sewage/microbiology , Phylogeny , RNA, Ribosomal, 16S/genetics , DNA, Bacterial/genetics , Sequence Analysis, DNA , Base Composition , Bacterial Typing Techniques , China , Phospholipids/chemistry
5.
Article in English | MEDLINE | ID: mdl-37185048

ABSTRACT

A Gram-stain-negative, strictly aerobic, rod-shaped and motile bacterium with bipolar flagella, designated G-43T, was isolated from a surface seawater sample collected from an aquaculture in Guangxi, PR China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain G-43T was most closely related to the family Oceanospirillaceae and distantly to the most closely related genera Venatorbacter and Thalassolituus (95.52 % and 94.45-94.76 % 16S rRNA gene sequence similarity, respectively), while similarity values to other Oceanospirillaceae type strains were lower than 94.0 %. Strain G-43T was found to grow at 4-30 °C (optimum, 25-28 °C), pH 6-9.0 (optimum, pH 7.0) and with 0-4.0 % NaCl (w/v; optimum at 2 % NaCl). Chemotaxonomic analysis of strain G-43T indicated that the sole respiratory quinone was ubiquinone-8, the predominant cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), and the major polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, aminolipid, diphosphatidylglycerol, phospholipids and an unidentified lipid. The G+C content of the genomic DNA was 55.4 mol%. The phylogenetic, genotypic, phenotypic and chemotaxonomic data demonstrate that strain G-43T represents a novel species in a novel genus within the family Oceanospirillaceae, for which the name Parathalassolituus penaei gen. nov., sp. nov. is proposed. Strain G-43T (=KCTC 72750T= CCTCC AB 2022321T) is the type and only strain of Parathalassolituus penaei.


Subject(s)
Oceanospirillaceae , Fatty Acids/chemistry , Phylogeny , RNA, Ribosomal, 16S/genetics , Sodium Chloride/analysis , Ponds , Bacterial Typing Techniques , DNA, Bacterial/genetics , China , Base Composition , Sequence Analysis, DNA , Phospholipids/chemistry
6.
J Chem Phys ; 140(14): 144907, 2014 Apr 14.
Article in English | MEDLINE | ID: mdl-24735318

ABSTRACT

The complex microstructures of drug particle/ABA star triblock copolymer in dilute solutions have been investigated by a theoretical approach which combines the self-consistent field theory and the hybrid particle-field theory. Simulation results reveal that, when the volume fraction of drug particles is smaller than the saturation concentration, the drug particle encapsulation efficiency is 100%, and micelle loading capacity increases with increasing particle volume fraction. When the volume fraction of drug particles is equal to the saturation concentration, the micelles attain the biggest size, and micelle loading capacity reaches a maximum value which is independent of the copolymer volume fraction. When the volume fraction of drug particles is more than the saturation concentration, drug particle encapsulation efficiency decreases with increasing volume fraction of drug particles. Furthermore, it is found that the saturation concentration scales linearly with the copolymer volume fraction. The above simulation results are in good agreement with experimental results.


Subject(s)
Drug Carriers , Models, Theoretical , Polymers/chemistry , Solutions/chemistry , Humans , Micelles , Phase Transition
7.
J Gen Virol ; 95(Pt 3): 691-699, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24272684

ABSTRACT

The genetic diversity of avian leukosis virus subgroup J (ALV-J) is determined not only by the env gene, but also by its 3' UTR and 3' LTR. They all play important roles in extending the host range and tumour development. In the present study, one ALV-J strain (ZB110604-6) from Black-Bone Silky Fowl (BSF) and three ALV-J strains (ZB110604-3/4/5) from grey partridge (GP), which bore multiple tumours and breed in one house of Farm A, were demonstrated extending their host to GP, while two other ALV-J strains (LC110515-3/4) from BSF of Farm B could not infect the embryo fibroblast of GP. The BSF is a unique species of chicken in China, while the GP is a close relative of the pheasant that previously demonstrated resistance to ALV-J. Histopathology showed that various tumours were induced by ALV-J in the two species. Phylogenetic tree analysis showed that the isolates from Farms A and B, rather than species, belong to two different clusters of ALV-J. Genetic mutations analysis revealed that the isolates obtained from Farm A showed a higher frequency of mutation in the hypervariable region 2 domain than in other variable regions of the gp85 gene. From the nucleotide alignment of the 3' UTR and 3' LTR gene, and the spectrum of tumours observed in this study, we speculate that the deletions or mutations in the redundant transmembrane region, E element and U3 (CAAT boxes, CArG box and Y box) might associate with tumour formation and development. The extension of the host range of ALV-J to the GP suggested that housing different species together provides more opportunities for ALV-J to evolve rapidly.


Subject(s)
Avian Leukosis Virus/genetics , Avian Leukosis Virus/physiology , Avian Leukosis/virology , Host Specificity , 3' Untranslated Regions , Amino Acid Sequence , Animals , Avian Leukosis Virus/classification , Avian Leukosis Virus/isolation & purification , Base Sequence , Galliformes , Molecular Sequence Data , Mutation , Phylogeny , Regulatory Elements, Transcriptional , Sequence Alignment , Viral Envelope Proteins/genetics , Viral Proteins/chemistry , Viral Proteins/genetics
8.
J Biol Chem ; 286(28): 25187-200, 2011 Jul 15.
Article in English | MEDLINE | ID: mdl-21606495

ABSTRACT

Regulation of neuronal NMDA receptor (NMDAR) is critical in synaptic transmission and plasticity. Protein kinase C (PKC) promotes NMDAR trafficking to the cell surface via interaction with NMDAR-associated proteins (NAPs). Little is known, however, about the NAPs that are critical to PKC-induced NMDAR trafficking. Here, we showed that calcium/calmodulin-dependent protein kinase II (CaMKII) could be a NAP that mediates the potentiation of NMDAR trafficking by PKC. PKC activation promoted the level of autophosphorylated CaMKII and increased association with NMDARs, accompanied by functional NMDAR insertion, at postsynaptic sites. This potentiation, along with PKC-induced long term potentiation of the AMPA receptor-mediated response, was abolished by CaMKII antagonist or by disturbing the interaction between CaMKII and NR2A or NR2B. Further mutual occlusion experiments demonstrated that PKC and CaMKII share a common signaling pathway in the potentiation of NMDAR trafficking and long-term potentiation (LTP) induction. Our results revealed that PKC promotes NMDA receptor trafficking and induces synaptic plasticity through indirectly triggering CaMKII autophosphorylation and subsequent increased association with NMDARs.


Subject(s)
Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Protein Kinase C/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Signal Transduction/physiology , Synaptic Membranes/metabolism , Animals , Calcium-Calmodulin-Dependent Protein Kinase Type 2/genetics , Enzyme Activation/physiology , Long-Term Potentiation/physiology , Male , Phosphorylation/physiology , Protein Kinase C/genetics , Protein Transport/physiology , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/genetics , Synaptic Membranes/genetics
9.
Neuropsychopharmacology ; 36(9): 1948-58, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21593734

ABSTRACT

Glycine in the hippocampus can exert its effect on both synaptic NMDA receptors (NMDARs) and extrasynaptic functional glycine receptors (GlyRs) via distinct binding sites. Previous studies have reported that glycine induces long-term potentiation (LTP) through the activation of synaptic NMDARs. However, little is known about the potential role of the activated GlyRs that are largely located in extrasynaptic regions. We report here that relatively high levels of glycine achieved either by exogenous glycine application or by the elevation of endogenous glycine accumulation with an antagonist of the glycine transporter induced long-term depression (LTD) of excitatory postsynaptic currents (EPSCs) in hippocampal CA1 pyramidal neurons. The co-application of glycine with the selective GlyR antagonist strychnine changed glycine-induced LTD (Gly-LTD) to LTP. Blocking the postsynaptic GlyR-gated net chloride flux by manipulating intracellular chloride concentrations failed to elicit any changes in EPSCs. These results suggest that GlyRs are involved in Gly-LTD. Furthermore, this new form of chemical LTD was accompanied by the internalization of postsynaptic AMPA receptors and required the activation of NMDARs. Therefore, our present findings reveal an important function of GlyR activation and modulation in gating the direction of synaptic plasticity.


Subject(s)
CA1 Region, Hippocampal/physiology , Glycine/physiology , Long-Term Synaptic Depression/physiology , Pyramidal Cells/physiology , Receptors, Glycine/physiology , Animals , CA1 Region, Hippocampal/drug effects , Excitatory Postsynaptic Potentials/drug effects , Excitatory Postsynaptic Potentials/physiology , Glycine/pharmacology , Glycine Plasma Membrane Transport Proteins/antagonists & inhibitors , Glycine Plasma Membrane Transport Proteins/physiology , Long-Term Synaptic Depression/drug effects , Male , Neural Inhibition/drug effects , Neural Inhibition/physiology , Organ Culture Techniques , Pyramidal Cells/drug effects , Rats , Rats, Sprague-Dawley , Receptors, Glycine/agonists , Receptors, Glycine/antagonists & inhibitors , Strychnine/pharmacology , Synaptic Transmission/drug effects , Synaptic Transmission/physiology
10.
Hippocampus ; 20(5): 646-58, 2010 May.
Article in English | MEDLINE | ID: mdl-19489005

ABSTRACT

Although an increasing number of studies have demonstrated the plasticity of NMDA receptor-mediated synaptic transmission, little is known about the molecular mechanisms that underlie this neurologically important process. In a study of NMDAR-mediated synaptic responses in hippocampal Schaffer-CA1 synapses whose AMPA receptor (AMPAR) activity is totally blocked, we uncovered differences between the trafficking mechanisms that underlie the long-term potentiation (LTP) and long-term depression (LTD) that can be induced in these cells under these conditions. The LTP-producing protocol failed to induce a change in the amplitude of NMDAR-mediated postsynaptic currents (NMDAR EPSCs) in the first 5-10 min, but induced gradual enhancement of NMDAR EPSCs thereafter that soon reached a stable magnitude. This "slow" LTP of NMDAR EPSCs (LTP(NMDA)) was blocked by inhibiting exocytosis or actin polymerization in postsynaptic cells. By contrast, LTD of NMDAR EPSCs (LTD(NMDA)) was immediately inducible, and, although it was blocked by the actin stabilizer, it was unaffected by exocytosis or endocytosis inhibitors. Furthermore, concomitant changes in the decay time of NMDAR EPSCs suggested that differential switches in NR2 subunit composition accompanied LTP(NMDA) and LTD(NMDA), and these changes were blocked by the calcium buffer BAPTA or an mGluR antagonist. Our results suggest that LTP(NMDA) and LTD(NMDA) utilize different NMDAR trafficking pathways and express different ratios of NMDAR subunits on the postsynaptic surface.


Subject(s)
Hippocampus/physiology , Long-Term Potentiation/physiology , Long-Term Synaptic Depression/physiology , Receptors, N-Methyl-D-Aspartate/metabolism , Synapses/physiology , Analysis of Variance , Animals , Biophysics , Bridged Bicyclo Compounds, Heterocyclic/pharmacology , Calcium/metabolism , Calcium Channel Blockers/pharmacology , Drug Interactions , Electric Stimulation , Endocytosis/drug effects , Enzyme Inhibitors/pharmacology , Excitatory Amino Acid Antagonists/pharmacology , Excitatory Postsynaptic Potentials/drug effects , Exocytosis/drug effects , Hippocampus/drug effects , In Vitro Techniques , Long-Term Potentiation/drug effects , Long-Term Synaptic Depression/drug effects , Male , Patch-Clamp Techniques/methods , Phalloidine/pharmacology , Piperidines/pharmacology , Protein Transport/drug effects , Protein Transport/physiology , Rats , Rats, Sprague-Dawley , Synapses/drug effects , Tetanus Toxin/pharmacology , Thiazolidines/pharmacology
11.
J Neurosci ; 29(27): 8764-73, 2009 Jul 08.
Article in English | MEDLINE | ID: mdl-19587283

ABSTRACT

In vivo experience induces changes in synaptic NMDA receptor (NMDAR) subunit components, which are correlated with subsequent modifications of synaptic plasticity. However, little is known about how these subunit changes regulate the induction threshold of subsequent plasticity. At hippocampal Schaffer collateral-CA1 synapses, we first examined whether a recent history of neuronal activity could affect subsequent synaptic plasticity through its actions on NMDAR subunit components. We found that prior activity history produced by priming stimulations (PSs) across a wide range of frequencies (1-100 Hz) could induce bidirectional changes in the NR2A/NR2B ratio, which governs the threshold for subsequent long-term potentiation/long-term depression (LTP/LTD). Manipulating the NR2A/NR2B ratio through partial NR2 subunit blockade mimicked the PS regulation of the LTP/LTD threshold. Our results demonstrate that activity-dependent changes in the NR2A/NR2B ratio can be critical factors in metaplastic regulation of the LTP/LTD threshold.


Subject(s)
Long-Term Potentiation/physiology , Long-Term Synaptic Depression/physiology , Neuronal Plasticity/physiology , Receptors, N-Methyl-D-Aspartate/physiology , Animals , Hippocampus/physiology , Male , Organ Culture Techniques , Rats , Rats, Sprague-Dawley
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