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Anemia of inflammation (AI) is associated with inflammatory diseases, and inflammation-induced iron metabolism disorder is the major pathogenic factor. Earlier studies have reported a tendency of AI in periodontitis patients, but the explicit relationship and possible pathological mechanisms remain unclear. Here, the analyses of both periodontitis patients and a mouse model of ligature-induced experimental periodontitis showed that periodontitis was associated with lower levels of hemoglobin and hematocrit with evidence of systemic inflammation (increased white blood cell levels) and evidence of iron restriction (low serum iron along with a high serum hepcidin and ferritin levels), in accordance with the current diagnosis criteria for AI. Moreover, periodontal therapy improved the anemia status and iron metabolism disorders. Furthermore, the increased level of hepcidin and significant correlation between hepcidin and key indicators of iron metabolism emphasized the pivotal role of hepcidin in the pathogenesis of periodontitis-related AI. Administration of the signal transducer and activator of transcription 3 (STAT3) inhibitors Stattic suggested that the IL-6–STAT3–hepcidin signaling pathway participated in this regulatory process. Together, these findings demonstrated that periodontitis should be considered an inflammatory disease that contributes to the development of AI; furthermore, IL-6–STAT3–hepcidin signaling pathway plays a key regulatory role in the pathogenesis of periodontitis-related AI. Our study will provide new insights into the systemic effects of periodontitis, while meaningfully expanding the spectrum of inflammatory diseases that contribute to AI.

Nitrogen cycle is an essential process for environmental health. Dirammox (direct ammonia oxidation), encoded by the dnfT1RT2ABCD cluster, was a novel pathway for microbial N2 production defined in Alcaligenes ammonioxydans HO-1. Here, a copy of the cluster dnfT1RT2ABCD as a whole was proved to have existed and very conserved in all Alcaligenes genomes. Phylogenetic analyses based on 16S rRNA gene sequences and amino acid sequences of DnfAs, together with G + C content data, revealed that dnf cluster was evolved associated with the members of the genus Alcaligenes. Under 20% O2 conditions, 14 of 16 Alcaligenes strains showed Dirammox activity, which seemed likely taxon-related. However, the in vitro activities of DnfAs catalyzing the direct oxidation of hydroxylamine to N2 were not taxon-related but depended on the contents of Fe and Mn ions. The results indicated that DnfA is necessary but not sufficient for Dirammox activity. The fact that members of the genus Alcaligenes are widely distributed in various environments, including soil, water bodies (both freshwater and seawater), sediments, activated sludge, and animal–plant-associated environments, strongly suggests that Dirammox is important to the nitrogen cycle. In addition, Alcaligenes species are also commonly found in wastewater treatment plants, suggesting that they might be valuable resources for wastewater treatment.

Nitrate accumulation causes long-time threat to aquatic animals in recirculating aquaculture system (RAS); thus, nitrate removal is also required in RASs. However, the lack of carbon sources makes denitrification difficult to function. Nitrate removal performance of an aerobic denitrifying and extracellular polyhydroxyalkanoate depolymerase–producing bacterium, Pseudomonas sp. AOB-7, using polyhydroxyalkanoate (PHA) granules as a solid sustained-release carbon source in RAS was evaluated. With the initial nitrate-N concentration of 140 mg/L, the high denitrification rates of 0.056 g NO3−-N L−1 day−1 and 0.035 g NO3−-N L−1 day−1 were achieved in denitrification medium containing poly-β-hydroxybutyrate (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), respectively. Significant erosions and pits formed on the surface of the granules made them a good biofilm carrier for AOB-7, and 3-hydroxybutyrate (3-HB) monomer was the major product released to aquatic phase, which was benefit to animals. SEM photos showed that AOB-7 entered and attached on the inside of the PHA particle holes. A 4-week application trial was conducted to reveal the effects of PHB (AOB-7) denitrifying agent and 3-HB produced on growth of zebrafish (Brachydanio rerio) by adding 0.1% (w/v) PHB (AOB-7) denitrifying agent. Result indicated that PHB (AOB-7) denitrifying agent can significantly reduce nitrate-N content in RASs. Compared with the control group, feed coefficient ratio reduced by 18% and weight gain ratio increased by 29% in the PHB (AOB-7) denitrifying agent group. 3-HB monomer produced during the denitrification was speculated to function as a prebiotic and promote zebrafish growth. • AOB-7 showed a good aerobic denitrifying ability on PHA granules as sustained-release C source. • PHB (AOB-7) denitrifying agent can significantly reduce nitrate content in RAS. • R-3-HB monomer was the major product released to aquatic phase and function as a prebiotic.

Ammonia oxidation is an important process in both the natural nitrogen cycle and nitrogen removal from engineered ecosystems. Recently, a new ammonia oxidation pathway termed Dirammox (direct ammonia oxidation, NH(3)→NH(2)OH→N(2)) has been identified in Alcaligenes ammonioxydans. However, whether Dirammox is present in other microbes, as well as its genetic regulation, remains unknown. In this study, it was found that the metabolically versatile bacterium Alcaligenes faecalis strain JQ135 could efficiently convert ammonia into N(2) via NH(2)OH under aerobic conditions. Genetic deletion and complementation results suggest that dnfABC is responsible for the ammonia oxidation to N(2) in this strain. Strain JQ135 also employs aerobic denitrification, mainly producing N(2)O and trace amounts of N(2), with nitrite as the sole nitrogen source. Deletion of the nirK and nosZ genes, which are essential for denitrification, did not impair the capability of JQ135 to oxidize ammonia to N(2) (i.e., Dirammox is independent of denitrification). Furthermore, it was also demonstrated that pod (which encodes pyruvic oxime dioxygenase) was not involved in Dirammox and that AFA_16745 (which was previously annotated as ammonia monooxygenase and is widespread in heterotrophic bacteria) was not an ammonia monooxygenase. The MocR-family transcriptional regulator DnfR was characterized as an activator of the dnfABC operon with the binding motif 5′-TGGTCTGT-3′ in the promoter region. A bioinformatic survey showed that homologs of dnf genes are widely distributed in heterotrophic bacteria. In conclusion, this work demonstrates that, besides A. ammonioxydans, Dirammox occurs in other bacteria and is regulated by the MocR-family transcriptional regulator DnfR. IMPORTANCE Microbial ammonia oxidation is a key and rate-limiting step of the nitrogen cycle. Three previously known ammonia oxidation pathways (i.e., nitrification, anaerobic ammonia oxidation [Anammox], and complete ammonia oxidation [Comammox]) are mediated by autotrophic microbes. However, the genetic foundations of ammonia oxidation by heterotrophic microorganisms have not been investigated in depth. Recently, a previously unknown pathway, termed direct ammonia oxidation to N(2) (Dirammox), has been identified in the heterotrophic bacterium Alcaligenes ammonioxydans HO-1. This paper shows that, in the metabolically versatile bacterium Alcaligenes faecalis JQ135, the Dirammox pathway is mediated by dnf genes, which are independent of the denitrification pathway. A bioinformatic survey suggests that homologs of dnf genes are widely distributed in bacteria. These findings enhance the understanding of the molecular mechanisms of heterotrophic ammonia oxidation to N(2).

Nitrogen cycle is an essential process for environmental health. Dirammox (

Heterotrophic nitrifiers are able to oxidize and remove ammonia from nitrogen-rich wastewaters but the genetic elements of heterotrophic ammonia oxidation are poorly understood. Here, we isolated and identified a novel heterotrophic nitrifier, Alcaligenes ammonioxydans sp. nov. strain HO-1, oxidizing ammonia to hydroxylamine and ending in the production of N

Heterotrophic nitrifiers are able to oxidize and remove ammonia from nitrogen-rich wastewaters but the genetic elements of heterotrophic ammonia oxidation are poorly understood. Here, we isolated and identified a novel heterotrophic nitrifier, Alcaligenes ammonioxydans sp. nov. strain HO-1, oxidizing ammonia to hydroxylamine and ending in the production of N2 gas. Genome analysis revealed that strain HO-1 encoded a complete denitrification pathway but lacks any genes coding for homologous to known ammonia monooxygenases or hydroxylamine oxidoreductases. Our results demonstrated strain HO-1 denitrified nitrite (not nitrate) to N2 and N2O at anaerobic and aerobic conditions respectively. Further experiments demonstrated that inhibition of aerobic denitrification did not stop ammonia oxidation and N2 production. A gene cluster (dnfT1RT2ABCD) was cloned from strain HO-1 and enabled E. coli accumulated hydroxylamine. Sub-cloning showed that genetic cluster dnfAB or dnfABC already enabled E. coli cells to produce hydroxylamine and further to 15N2 from (15NH4)2SO4. Transcriptome analysis revealed these three genes dnfA, dnfB and dnfC were significantly upregulated in response to ammonia stimulation. Taken together, we concluded that strain HO-1 has a novel dnf genetic cluster for ammonia oxidation and this dnf genetic cluster encoded a previously unknown pathway of direct ammonia oxidation (Dirammox) to N2.

Nowadays, contamination by polycyclic aromatic hydrocarbons (PAHs) has become a serious problem all over the world; in particular, high-molecular-weight PAHs (HWM PAHs, four to seven rings) are more harmful to human health and environment due to their more complex structure and metabolic pathway. Biodegradation of PAHs with six or more rings, such as indeno[1,2,3-cd]pyrene (IcdP), was rarely described. An IcdP-degrading strain, Rhodococcus aetherivorans IcdP1, was isolated from HWM PAH-contaminated soil. It could grow on and efficiently degrade various HWM PAHs, such as IcdP, benzo[a]pyrene, and benzo[j]fluoranthene. It showed highest degrading ability toward IcdP (> 70% within 10 days). The IcdP degradation was initiated by ring hydroxylation with multiple pathways, including the hydroxylation at the 1,2 and 7,8 positions, according to the relevant metabolites detected, e.g., cyclopenta[cd]pyrene-3,4-dicarboxylic acid and 2,3-dimethoxy-2,3-dihydrofluoranthene. The transcriptional patterns of the genes encoding ring-hydroxylating oxygenases (RHOs) and cytochrome P450 monooxygenases (CYP450s) under the induction of IcdP, pyrene, and benzo[b]fluoranthene (BbF) were compared to determine the key initial RHOs in the conversion of IcdP. The expression of genes encoding RHOs 1892–1894, 1917–1920, and 4740–4741 was induced strictly by IcdP, and the amino acid sequences of these proteins showed very low identities with their homologs. These results suggested that IcdP was degraded through a dioxygenation-initiated metabolism pattern, and RHOs 1892–1894, 1917–1920, and 4740–4741 responded to the initial ring cleavage of IcdP through 1,2-dihydrodiol or 7,8-dihydrodiol. The studies would contribute to the understanding of the molecular mechanism of initial degradation of IcdP.

Hydroxylamine is a key intermediate of microbial ammonia oxidation and plays an important role in the biogeochemical cycling of N-compounds. Hydroxylamine is oxidized to NO or N2O by hydroxylamine oxidases or cytochrome P460 from heterotrophic or autotrophic bacteria, but its enzymatic oxidation to N2 has not yet been observed. Here, we report on the discovery of a novel oxidase that converts hydroxylamine to N2 from the newly isolated heterotrophic nitrifier Alcaligenes strain HO-1. Strain HO-1 accumulated hydroxylamine and produced N2 from ammonia oxidation. Using transcriptome analysis and heterologous expression via fosmid library screening, we identified three genes (dnfABC) of strain HO-1 that enabled E. coli cells not only to produce hydroxylamine from 15N-labelled ammonium but also to further convert it to 15N2. The three genes were individually cloned and expressed, and their translational products DnfA, DnfB, and DnfC were purified. In vitro DnfA bound to hydroxylamine and catalyzed the conversion of hydroxylamine to N2 in the presence of FAD, NADH and O2. Thus, DnfA was identified as a novel hydroxylamine oxidase and catalyzed a previously unknown N-N bond forming reaction with a yet-to-be discovered mechanism. DnfA homologs were detected in different bacterial groups, suggesting that hydroxylamine oxidation to nitrogen might occur in additional microbial taxa.

Background: MCM3AP-AS1 is a recently characterized lncRNA in hepatocellular carcinoma (HCC) and (GBM). We found that miR-148a may be able to bind MCM3AP-AS1. We explored the functions of lncRNA MCM3AP-AS1 in small cell lung cancer (SCLC). Methods: Gene expression in SCLC patients was analyzed by qPCR. Transient transfections were performed to analyze gene interactions. Cell invasion and migration were analyzed by Transwell assays.Results: We found that MCM3AP-AS1 was upregulated in SCLC and high expression levels were accompanied by low survival rate. Bioinfromatics analysis showed that MCM3AP-AS1 may bind miR-148a, which can target ROCK1. In SCLC tissues, MCM3AP-AS1 was positively correlated with ROCK1. In SCLC cells, MCM3AP-AS1 overexpression mediated the upregulated ROCK1 expression and increased cell invasion and migration rates. However, MCM3AP-AS1 and miR-148a could not regulate each other. However, miR-148a overexpressed led to downregulated ROCK1 expression, decreased cell invasion and migration rates, and reduced effects of MCM3AP-AS1 overexpression. Conclusions: Therefore, MCM3AP-AS1 may sponge miR-148a to cell invasion and migration in SCLC through the upregulation of ROCK1.

Nowadays, contamination by polycyclic aromatic hydrocarbons (PAHs) has become a serious problem all over the world; in particular, high-molecular-weight PAHs (HWM PAHs, four to seven rings) are more harmful to human health and environment due to their more complex structure and metabolic pathway. Biodegradation of PAHs with six or more rings, such as indeno[1,2,3-cd]pyrene (IcdP), was rarely described. An IcdP-degrading strain, Rhodococcus aetherivorans IcdP1, was isolated from HWM PAH-contaminated soil. It could grow on and efficiently degrade various HWM PAHs, such as IcdP, benzo[a]pyrene, and benzo[j]fluoranthene. It showed highest degrading ability toward IcdP (> 70% within 10 days). The IcdP degradation was initiated by ring hydroxylation with multiple pathways, including the hydroxylation at the 1,2 and 7,8 positions, according to the relevant metabolites detected, e.g., cyclopenta[cd]pyrene-3,4-dicarboxylic acid and 2,3-dimethoxy-2,3-dihydrofluoranthene. The transcriptional patterns of the genes encoding ring-hydroxylating oxygenases (RHOs) and cytochrome P450 monooxygenases (CYP450s) under the induction of IcdP, pyrene, and benzo[b]fluoranthene (BbF) were compared to determine the key initial RHOs in the conversion of IcdP. The expression of genes encoding RHOs 1892–1894, 1917–1920, and 4740–4741 was induced strictly by IcdP, and the amino acid sequences of these proteins showed very low identities with their homologs. These results suggested that IcdP was degraded through a dioxygenation-initiated metabolism pattern, and RHOs 1892–1894, 1917–1920, and 4740–4741 responded to the initial ring cleavage of IcdP through 1,2-dihydrodiol or 7,8-dihydrodiol. The studies would contribute to the understanding of the molecular mechanism of initial degradation of IcdP.

The bacterium Aeromonas salmonicida is the causative agent of furunculosis, a systemic, ubiquitous disease of fish in the salmon family, characterized by high mortality and morbidity. Probiotics are a promising approach for prevention of furunculosis in aquaculture. A bacterial strain with anti-A. salmonicida properties, Bacillus velezensis V4, was isolated and the mechanisms underlying these properties were investigated. Anti-A. salmonicida compounds present in cell-free supernatant of V4 were purified and structurally identified as members of the iturin, macrolactin, and difficidin groups. The compounds contributed jointly to inhibition of A. salmonicida, and the diversity of the compounds was related to the versatility of their mode of action. Addition of the compounds to A. salmonicida cell suspensions reduced cell density. Analyses by confocal microscopy and scanning electron microscopy revealed cell membrane disruption, deletion of cellular content, and cell lysis of A. salmonicida. The V4 genome was sequenced, and gene clusters involved in synthesis of anti-Aeromonas compounds were detected and identified. A possible probiotic effect on growth performance of Oncorhynchus mykiss (rainbow trout) was investigated by addition of 0, 1, and 3 % (v/w) V4. Relative to control, mortality was reduced 27.25 % in the 1 % addition group and 81.86 % in the 3 % addition group. Feed coefficient ratio was reduced 19.49 % and weight gain ratio was increased 71.22 % in the 1 % addition group. Our findings demonstrate that V4 is an effective probiotic strain in O. mykiss and has clear potential for both control of furunculosis and growth promotion of aquaculture animals.

Counter anion and pH play important roles in the self-assembly process of coordination compounds. Tetrazole carboxylate ligands are outstanding candidates for construction of coordination architectures. Four new compounds based on Htzpya, Hatzpa, Hpytza and europium(III) salts, namely mononuclear [Eu(tzpya)2(H2O)5]Cl·4H2O (1), binuclear [Eu2(atzpa)4(H2O)8](NO3)2·2H2O (2), one dimensional [Eu(pytza)3(H2O)2]n·2nH2O (3) and [Eu(pytza)2(H2O)4]nCln (4) were obtained, where Htzpya = 3-(5-tetrazolyl)pyridine-1-acetic acid, Hatzpa = 5-aminotetrazole-1-propanoic acid and Hpytza = 5-(4-pyridyl) tetrazole-2-acetic acid. Different europium(III) salts EuX3·6H2O (X = Cl−, NO3−) and pH values were selected to investigate the influence of both the counter anions and the pH on the formation of such compounds. Furthermore, the luminescence properties of 1–4 in the solid state were also investigated at room temperature, showing both intraligand emission and characteristic peaks of Eu3+ for compounds 1–4.

Two novel coordination compounds, [Sr(atzp)2(H2O)2]·CH3OH (1) and [Sr(dtzpha)(H2O)3]·4H2O (2) [Hatzp=5-aminotetrazole-1-propionic acid, H2dtzpha=1,3-di(tetrazol-5-yl)benzene-N2,N2′-diacetic acid)], have been generated by using 5-aminotetrazole-1-propionic acid and 1,3-di(tetrazol-5-yl)benzene-N2,N2′-diacetic acid to react with strontium salts, respectively. X-ray diffraction analysis reveals that carboxylic groups of two ligands show the same coordination mode (the μ 1,1,3-COO coordination mode), compound 1 displays a 1D structure while compound 2 shows a 2D structure, which implies the influence of the number of the carboxylic acid groups. Luminescence properties of 1 and 2 were investigated at room temperature in the solid state.

Psychrophilic enzymes play crucial roles in cold adaptation of microbes and provide useful models for studies of protein evolution, folding, and dynamic properties. We examined the crystal structure (2.2-Å resolution) of the psychrophilic β-glucosidase BglU, a member of the glycosyl hydrolase 1 (GH1) enzyme family found in the cold-adapted bacterium Micrococcus antarcticus . Structural comparison and sequence alignment between BglU and its mesophilic and thermophilic counterpart enzymes (BglB and GlyTn, respectively) revealed two notable features distinct to BglU: (i) a unique long-loop L3 (35 versus 7 amino acids in others) involved in substrate binding and (ii) a unique amino acid, His299 (Tyr in others), involved in the stabilization of an ordered water molecule chain. Shortening of loop L3 to 25 amino acids reduced low-temperature catalytic activity, substrate-binding ability, the optimal temperature, and the melting temperature ( T m ). Mutation of His299 to Tyr increased the optimal temperature, the T m , and the catalytic activity. Conversely, mutation of Tyr301 to His in BglB caused a reduction in catalytic activity, thermostability, and the optimal temperature (45 to 35°C). Loop L3 shortening and H299Y substitution jointly restored enzyme activity to the level of BglU, but at moderate temperatures. Our findings indicate that loop L3 controls the level of catalytic activity at low temperatures, residue His299 is responsible for thermolability (particularly heat lability of the active center), and long-loop L3 and His299 are jointly responsible for the psychrophilic properties. The described structural basis for the cold adaptedness of BglU will be helpful for structure-based engineering of new cold-adapted enzymes and for the production of mutants useful in a variety of industrial processes at different temperatures.

Isomer is sometimes fundamental to the formation of the resulting compounds. The design and preparation of coordination compounds based on isomers is of tremendous paramount since they have a lot in common but simultaneously some difference, which can lead to variation of both the topologies and properties. Solvothermal reactions of Hn-pytza (n = 3, 4) with Co(ClO4)2·6H2O, afforded two interesting coordination polymers, one dimensional [Co(3-pytza)2(H2O)2]n·2nH2O (1) and three dimensional [Co(4-pytza)2]n (2), where Hn-pytza = 5-(n-pyridyl)tetrazole-2-acetic acid (n = 3, 4). The thermal decomposition behavior of the two compounds were characterized by the differential scanning calorimetry (DSC) and thermogravimetric-differential thermogravimetric (TG-DTG), showing [Co(4-pytza)2]n is superior to [Co(3-pytza)2(H2O)2]n·2nH2O in terms of energetic performance. Furthermore, the entropy of activation (∆S), enthalpy of activation (∆H), and free energy of activation (∆G) were calculated, as well.

Background A major obstacle to industrial-scale astaxanthin production by the yeast Phaffia rhodozyma is the strong inhibitory effect of high glucose concentration on astaxanthin synthesis. We investigated, for the first time, the mechanism of the regulatory effect of high glucose (> 100 g/L) at the metabolite and transcription levels. Results Total carotenoid, β-carotene, and astaxanthin contents were greatly reduced in wild-type JCM9042 at high (110 g/L) glucose; in particular, β-carotene content at 24–72 h was only 14–17% of that at low (40 g/L) glucose. The inhibitory effect of high glucose on astaxanthin synthesis appeared to be due mainly to repression of lycopene-to-β-carotene and β-carotene-to-astaxanthin steps in the pathway. Expression of carotenogenic genes crtE, pbs, and ast was also strongly inhibited by high glucose; such inhibition was mediated by creA, a global negative regulator of carotenogenic genes which is strongly induced by glucose. In contrast, astaxanthin-overproducing, glucose metabolic derepression mutant strain MK19 displayed de-inhibition of astaxanthin synthesis at 110 g/L glucose; this de-inhibition was due mainly to deregulation of pbs and ast expression, which in turn resulted from low creA expression. Failure of glucose to induce the genes reg1 and hxk2, which maintain CreA activity, also accounts for the fact that astaxanthin synthesis in MK19 was not repressed at high glucose. Conclusion We conclude that astaxanthin synthesis in MK19 at high glucose is enhanced primarily through derepression of carotenogenic genes (particularly pbs), and that this process is mediated by CreA, Reg1, and Hxk2 in the glucose signaling pathway.

Bacterial community dynamics of the ANAMMOX reactor of an integrated “UASB + SHARON + ANAMMOX” system for treating piggery wastewater were investigated using the Illumina MiSeq method with samples obtained at ~ 2-week intervals during a 314-day period. With aerobic activated sludge as seeds and low content artificial wastewater (NH4+–N 50 mg/L; NO2−–N 55 mg/L) as influent for the ANAMMOX reactor, nitrogen removal was initially observed on day 38 with a removal rate 1.3 mg N L−1 day−1, and increased to 90.4 mg N L−1 day−1 on day 55 with almost complete removal of ammonia and nitrite, indicating a successful startup of the reactor. Increasing influent load stepwise to NH4+–N 272.7 mg/L/NO2−–N 300 mg/L, nitrogen removal rate increased gradually to 470 mg N L−1 day−1 on day 228, and maintained a stable level (~ 420 mg N L−1 day−1) following introduction of SHARON effluent since day 229. Correlation between microbial community dynamics and nitrogen removal capability was significant (r = 0.489, p 300 mg/L), suggesting their different niches and application for different loads. These findings improve the understanding of relationships among microbial community/functional taxa, running parameters and reactor performance, and will be useful in optimizing running parameters for rapid startup and high, stable efficiency. Electronic supplementary material The online version of this article (10.1186/s13568-018-0686-0) contains supplementary material, which is available to authorized users.

An efficient heterotrophic nitrifying/aerobic denitrifying strain, Photobacterium sp. NNA4 was isolated from a recirculating aquaculture system (RAS). NNA4 was capable of utilizing ammonia, nitrate or nitrite as sole N-source with maximal removal rates of 12.5 mg/L/h for NH4+ N, 16.4 mg/L/h for NO3--N, and 4.5 mg/L/h for NO2--N, respectively. Optimal nitrification conditions were: sodium succinate as C-source, 30–37°C, NaCl 1–4%, pH 7.0–8.0, dissolved oxygen 5.89 mg/L, C/N > 10. Gas chromatography/mass spectrometry and gas chromatography/isotope ratio mass spectrometry analyses showed that N2 and N2O were aerobic denitrification products of nitrite and nitrate. NNA4 could tolerate high concentration of hydroxylamine and displayed efficient hydroxylamine-transforming capability. Hydroxylamine oxidoreductase activity using potassium ferricyanide as electron acceptor was 0.042 U. Results revealed that strain NNA4 could oxidize NH2OH directly to N2O at aerobic conditions. In view of its high removal ability of inorganic nitrogen pollutants and broad salinity tolerance range, NNA4 has great potential in denitrification treatment of types of wastewater with either low salinity (e.g., municipal facilities) or high salinity (e.g., aquaculture, seafood processing).

To mine the medication rules of herbal prescriptions for gout caused by heat-damp accumulation syndrome, and explore the possible mechanism of the core herbs, we collected the relevant literature of gout caused by heat-damp accumulation syndrome in CNKI, medication rules of herbal prescriptions are analyzed by using TCMISS(V2.5) software, and the compatibility of core drugs and new prescriptions were mined.KEGG pathway analysis was performed by BATMAN-TCM, an online analysis tool, and the potential signaling pathways of core drugs compatibility to treat gout caused by heat-damp accumulation syndrome were revealed. The results showed that six core drugs and three new prescriptions were found out of the 136 prescriptions. The core compatibility herbs in clinical treament of gout caused by heat-damp accumulation syndrome, Phellodendri Chinrnsis Cortex, Achyranthis Bidentatae Radix and Achyranthis Bidentatae Radix, which potential signaling pathways were purine metabolic pathway and neura activity ligand receptor interaction signaling pathway. Therefore, for gout caused by heat-damp accumulation syndrome, the mainly used therapies of TCM were clearing heat and drying dampness,inducing diuresis for removing edema, dispeling wind and eliminating dampness. The mechnisms of core compatibility herbs may be achieved through the intervention of purine metabolic pathway and neural activity ligand receptor interaction signaling pathway.

Nitrogen pollution is an increasingly severe worldwide problem because of drainage of nitrogen-containing wastewater and intensive application of nitrogen-containing fertilizers. Denitrification, a key process in nitrogen cycles, is commonly employed for nitrogen removal in engineered wastewater treatment systems. Biological denitrification is performed by denitrifying microbes (bacteria) that use nitrate as terminal electron acceptor. Better understanding the functions of diverse microbial populations in denitrification-based wastewater treatment systems, and the interactions of these populations with operating environments, is essential for improving both treatment performance and system stability. Recent advances in "meta-omics" (e. g., genomics, transcriptomics, proteomics, metabolomics), other molecular biology tools, and microbiome analysis have greatly enhanced such understanding. This minireview summarizes recent findings regarding microbial community structure and composition, key functional microbes and their physiology, functional genes involved in nitrogen cycle, and responses of microbes and their genes to changes of environmental factors or operating parameters, in denitrification processes in wastewater treatment systems. Of particular interest are heterotrophic denitrification systems (which require alternative organic carbon sources) and the autotrophic denitrification systems (which do not require an external carbon source). Integrated microbiome and -omics approaches have great future potential for determination of optimal environmental and biotechnological parameters, novel process development, and improvement of nitrogen removal efficiency and system stability.

Optimization of running parameters in a bioreactor requires detailed understanding of microbial community dynamics during the startup and running periods. Using a novel piggery wastewater treatment system termed “UASB + SHARON + ANAMMOX” constructed in our laboratory, we investigated microbial community dynamics using the Illumina MiSeq method, taking activated sludge samples at ~2-week intervals during a ~300-day period. Ammonia-oxidizing bacteria (AOB) were further investigated by quantification of AOB amoA genes and construction of gene clone libraries. Major changes in bacterial community composition and dynamics occurred when running manner was changed from continuous flow manner (CFM) to sequencing batch manner (SBM), and when effluent from an upflow anaerobic sludge blanket (UASB) reactor for practical treatment of real piggery wastewater was used as influent; differences among these three experimental groups were significant (R2 = 0.94, p

To investigate the expression of PIGF and its receptor Flt-1 in patients with multiple myeloma, and to analyze their correlation with the efficacy of thalidomide-based chemotherapy so as to provide further theoretical basis for individualized treatment.A total of 35 patients diagnosed as multiple myeloma from June 2012 to March 2013 in our hospital and 15 non-tumor patients as controls were enrolled in this study. MM patients were treated with thalidomide-based chemotherapy for 3 months, and then were grouped according to the curative effecacy. The expression levels of PIGF and Flt-1 were detected in bone marrow of control and MM patient group by RT-PCR and Western blot before and after chemotherapy, their correlation with chemotherapeutic efficacy was analyzed. Serum concentrations of PITG and Flt-1 were detected in control and MM patients before and after chemotherapy by ELISA and their correlation with the chemotherapeutic efficacy was analyzed.The effective rate of three-months-thalidomide-based chemotherapy was 54.3% in MM patients. The expression levels of PIGF and Flt-1 in MM patients' bone marrow were obviously higher than those in controls. After chemotherapy, PIGF and Flt-1 expression levels significantly reduced and the decline level was positively correlated with curative effecacy(r=0.71). The serum concentrations of PIGF and Flt-1 in MM patients' bone marrow were obviously higher than those in control. After chemotherapy, serum concentrations of PIGF and Flt-1 were significantly decreased and the decline level positively correlated with curative effecacy(r=0.87).PIGF and FLT-1 are highly expressed in patients with multiple myeloma, and their expression levels positively correlates with curative effecacy of thalidomide-based chemotherapy.

Psychrophilic enzymes display efficient activity at moderate or low temperatures (4–25 °C) and are therefore of great interest in biotechnological industries. We previously examined the crystal structure of BglU, a psychrophilic β-glucosidase from the bacterium Micrococcus antarcticus, at 2.2 A resolution. In structural comparison and sequence alignment with mesophilic (BglB) and thermophilic (GlyTn) counterpart enzymes, BglU showed much lower contents of Pro residue and of charged amino acids (particularly positively charged) on the accessible surface area. In the present study, we investigated the roles of specific amino acid residues in the cold adaptedness of BglU. Mutagenesis assays showed that the mutations G261R and Q448P increased optimal temperature (from 25 to 40–45 °C) at the expense of low-temperature activity, but had no notable effects on maximal activity or heat lability. Mutations A368P, T383P, and A389E significantly increased optimal temperature (from 25 to 35–40 °C) and maximal activity (~1.5-fold relative to BglU). Thermostability of A368P and A389E increased slightly at 30 °C. Mutations K163P, N228P, and H301A greatly reduced enzymatic activity—almost completely in the case of H301A. Low contents of Pro, Arg, and Glu are important factors contributing to BglU’s psychrophilic properties. Our findings will be useful in structure-based engineering of psychrophilic enzymes and in production of mutants suitable for a variety of industrial processes (e.g., food production, sewage treatment) at cold or moderate temperatures.

The bacterial strain F6 was isolated from a biological aerated filter that is used for purifying recirculating water in a marine aquaculture system and was identified as Marinobacter sp. based on the analysis of its 16S rRNA gene sequence. Strain F6 showed efficient aerobic denitrifying ability. One hundred percent of nitrates and 73.10% of nitrites were removed, and the total nitrogen (TN) removal rates reached 50.08% and 33.03% under a high nitrate and nitrite concentration in the medium, respectively. N2O and 15N2, as revealed by GC–MS and GC–IRMS, were the products of aerobic denitrification. Factors affecting the growth and aerobic denitrifying performance of strain F6 were investigated. The results showed that the optimum aerobic denitrification conditions for strain F6 were the presence of sodium succinate as a carbon source, a C/N ratio of 15, salinity ranging from 32–35 g/L of NaCl, incubation temperature of 30°C, an initial pH of 7.5, and rotation speed of 150 rpm [dissolved oxygen (DO) 6.75 mg/L]. In addition, strain F6 was confirmed to be a heterotrophic nitrifier through its NO 2 − generation and 25.96% TN removal when NH4+ was used as the sole N source. Therefore, strain F6, the first reported member of genus Marinobacter with aerobic heterotrophic nitrifying–denitrifying ability, is an excellent candidate for facilitating simultaneous nitrification and denitrification (SND) in industry and aquaculture wastewater.

The gene bglU encoding a cold-adapted β-glucosidase (BglU) was cloned from Micrococcus antarcticus . Sequence analysis revealed that the bglU contained an open reading frame of 1419 bp and encoded a protein of 472 amino acid residues. Based on its putative catalytic domains, BglU was classified as a member of the glycosyl hydrolase family 1 (GH1). BglU possessed lower arginine content and Arg/(Arg + Lys) ratio than mesophilic GH1 β-glucosidases. Recombinant BglU was purified with Ni2+ affinity chromatography and subjected to enzymatic characterization. SDS-PAGE and native staining showed that it was a monomeric protein with an apparent molecular mass of 48 kDa. BglU was particularly thermolabile since its half-life time was only 30 min at 30 °C and it exhibited maximal activity at 25 °C and pH 6.5. Recombinant BglU could hydrolyze a wide range of aryl-β-glucosides and β-linked oligosaccharides with highest activity towards cellobiose and then p -nitrophenyl-β- d -glucopyranoside (pNPG). Under the optimal conditions with pNPG as substrate, the K m and k cat were 7 mmol/L and 7.85 × 103/s, respectively. This is the first report of cloning and characterization of a cold-adapted β-glucosidase belonging to GH1 from a psychrotolerant bacterium.

An efficient aerobic denitrification bacterium, strain NNA5, was isolated and identified as Marinobacter sp. NNA5. NNA5 did not perform heterotrophic nitrification. GC/IRMS analysis revealed that (15)N2 was produced from Na(15)NO2 and K(15)NO3. GC/MS and quantitative analyses showed that no N2O emission occurred when nitrite or nitrate was used as substrate. Single factor experiments indicated that optimal conditions for aerobic denitrification were: sodium succinate or sodium pyruvate as carbon source, temperature 35 °C, NaCl concentration 2-4%, C/N ratio 6-8, pH 7.5, rotation speed 150 rpm (giving dissolved oxygen concentration 6.08 mg/L), NO3(-)-N concentration ranging from 140 to 700 mg/L. NNA5 displayed highly efficient aerobic denitrifying ability, with maximal NO3(-)-N removal rate 112.8 mg/L/d. In view of its ability to perform aerobic denitrification with zero N2O emission, NNA5 has great potential for future application in aerobic denitrification processes in industrial and aquaculture wastewater treatment systems.

The prokaryotic community composition and diversity and the distribution patterns at various taxonomic levels across gradients of salinity and physiochemical properties in the surface waters of seven plateau lakes in the Qaidam Basin, Tibetan Plateau, were evaluated using Illumina MiSeq sequencing. These lakes included Lakes Keluke (salinity, Bacteria in lakes with salinities of Archaea in Lake Gasikule. The clades At12OctB3 and Salinibacter , previously reported only in hypersaline environments, were found in a hyposaline lake (salinity, 5.5 to 6.6 g/liter) at an abundance of ∼1.0%, indicating their ecological plasticity. Salinity and the concentrations of the chemical ions whose concentrations covary with salinity (Mg 2+ , K + , Cl − , Na + , SO 4 2− , and Ca 2+ ) were found to be the primary environmental factors that directly or indirectly determined the composition and diversity at the level of individual clades as well as entire prokaryotic communities. The distribution patterns of two phyla, five classes, five orders, five families, and three genera were well predicted by salinity. The variation of the prokaryotic community structure also significantly correlated with the dissolved oxygen concentration, pH, the total nitrogen concentration, and the PO 4 3− concentration. Such correlations varied depending on the taxonomic level, demonstrating the importance of comprehensive correlation analyses at various taxonomic levels in evaluating the effects of environmental variable factors on prokaryotic community structures. Our findings clarify the distribution patterns of the prokaryotic community composition in plateau lakes at the levels of individual clades as well as whole communities along gradients of salinity and ionic concentrations.

Reactions of [Zn(Tab)(4)](PF(6))(2) (Tab = 4-(trimethylammonio)benzenethiolate) (1) with 2,2'-bipyridine (2,2'-bipy), 1,10-phenanthroline (phen), 2,9-dimethyl-1,10-phenanthroline (2,9-dmphen), N-methylimidazole (N-Meim), and 2,6-bis(pyrazol-3-yl)pyridine (bppy) or with CoCl(2)·6H(2)O at the presence of N-donor ligands (2,2'-bipy, phen, 4,4'-dimethyl-2,2'-bipyridine (4,4'-dmbpy), 2,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)pyridine (bdmppy))gave rise to a family of zinc or cobalt thiolate complexes, [Zn(Tab)(2)(L)](PF(6))(2) (2: L = 2,2'-bipy, 3: L = phen, 4: L = 2,9-dmphen), [Zn(Tab)(2)(N-Meim)(2)](PF(6))(2) (5), [Zn(Tab)(2)(bppy)](PF(6))(2) (6), [Co(Tab)(2)(L)(2)](PF(6))(3) (7: L = 2,2'-bipy, 8: L = phen, 9: L = 4,4'-dmbpy), and [Co(Tab)(bdmppy)Cl](PF(6)) (10). These compounds were characterized by elemental analysis, IR spectra, UV-vis spectra,(1)H NMR, electrospray ionization (ESI) mass spectra, and single-crystal X-ray diffraction. The Zn(II) in [Zn(Tab)(2)L(n)](2+)dications of 2-5 is tetrahedrally coordinated by two Tab ligands and one L or two N-Meim ligands. In 6, the Zn(II) has a distorted trigonal-bipyramidal geometry, coordinated by two Tab ligands and one tridentate bppy ligand. The Co(III) in the [Co(Tab)(2)(L)(2)](3+) trications of 7-9 is octahedraly chelated by two bidentate L ligands and two Tab ligands. In 10, the Co(II) adopts a distorted trigonal-bipyramidal geometry, coordinated by one Cl(-), one Tab ligand, and one tridentate bdmppy. In the formation of 2-6, two Tab ligands are removed from the [Zn(Tab)(4)](2+) dication when it is attacked by L ligands, while in the cases of 7-9, the Zn(II) of the [Zn(Tab)(4)](2+) dication was replaced by Co(III) (derived from oxidation of Co(II) by O(2)) followed by the removal of two Tab ligands via L ligands. In the case of 10, the central Zn(II) of the [Zn(Tab)(4)](2+) dication was displaced by Co(II) followed by the removal of three Tab ligands via one Cl(-) and one tridentate bdmppy. These ligand and metal replacement reactions may provide some interesting information on the interactions of the [Zn(S-Cys)(4)](2-) unit of Zn-MTs with N-heterocyclic ligands and toxic metal ions encountered in a natural environment.

Treatment of [CuCl(2)(bppyH(2))] (1, bppyH(2) = 2,6-di(1H-pyrazol-3-yl)pyridine) with 2 equiv. of AgNO(3) in DMF gave rise to a binuclear Cu(II) complex [Cu(2)(bppyH)(2)(NO(3))(2)] (bppyH = 2-(pyrazol-3-yl)-6-(pyrazolate)pyridine) (2). Complex 2 was characterized by elemental analysis, IR and single crystal X-ray diffraction. Complex 2 has a dimeric structure in which the two Cu(ii) centers are bridged by a couple of the in situ-generated bppyH(-) anions. Each Cu(II) center is further coordinated by one O atom of a NO(3)(-) anion and three N atoms of one bppyH(-) anion. Complex 2 exhibited a higher catalytic activity in the polymerization of methyl methacrylate (MMA) than the precursor complex 1. Even though the ratio of catalyst to MMA was raised up to 1 : 1500, the PDI for 2 (reaction time was fixed at 4 h) is 1.63 and the conversion is up to 72%. The effects of solvent, reaction temperature and the ratio of MMA to catalyst were also investigated.

Bacillus methylotrophicus strain L7, exhibited efficient heterotrophic nitrification-aerobic denitrification ability, with maximum NH(4)(+)-N and NO(2)(-)-N removal rate of 51.58 mg/L/d and 5.81 mg/L/d, respectively. Strain L7 showed different gaseous emitting patterns from those strains ever described. When (15)NH(4)Cl, or Na(15)NO(2), or K(15)NO(3) was used, results of GC-MS indicated that N(2)O was emitted as the intermediate of heterotrophic nitrification or aerobic denitrification, while GC-IRMS results showed that N(2) was produced as end product when nitrite was used. Single factor experiments suggested that the optimal conditions for heterotrophic nitrification were sodium succinate as carbon source, C/N 6, pH 7-8, 0 g/L NaCl, 37 °C and a wide range of NH(4)(+)-N from 80 to 1000 mg/L. Orthogonal tests showed that the optimal conditions for aerobic denitrification were C/N 20, pH 7-8, 10 g/L NaCl and DO 4.82 mg/L (shaking speed 50 r/min) when nitrite was served as substrate.

Counter party credit risk of the financial derivatives transaction is the risk that one party has a default before the expiration of the contract. This research investigates the unilateral counter party credit risk of credit default swap (CDS). Under different assumptions, three different information models are built. They are, the basic model with no counter party credit risk, the model considering unilateral counter party risk, and the model considering unilateral counter party risk as well as the collateral. Through comparing and analyzing these models, the conclusion is: considering counter party credit risk in the transaction process facilitates trading in a cautious manner, nevertheless, because of the assessment accuracy issue for the counter party credit risk, the success of such transactions may result in concentration of risk in the market, the collateral factors can increase the expected income and consequently promote the transactions. However, since it may be insufficient to eliminate counter party credit risk through the collateral, investors may still suffer from unexpected losses. In the end, the development of the CDS market before and after the financial crisis from the perspective of the counter party credit risk is analyzed.

To investigate the potential role of angiopoietin-2 in the rats model of lipopolysaccharide (LPS)-induced acute lung injury (ALI).Wistar rats were randomly divided into four groups(n=10): control group; in LPS groups, rats were divided into three subgroups, treated with different dosage of LPS (2 mg/kg, 4 mg/kg and 8 mg/kg). ALI model was established by intravenous injection with LPS, while control group was with NS. The lung histopathology change was observed by HE stain. Western blot was used to measure the expression of Ang-2 in serum.Histologically, alveolar edema, hemorrhage, and massive inflammatory cell, infiltration were observed in LPS groups, but not in control group. The pathological score in LPS groups were significantly higher than that in NS group. Compared with 2 mg/kg LPS group, the pathological score in 4 mg/kg LPS group was significantly higher. While the pathological score in 8 mg/kg LPS group was higher than those in other LPS groups. The expression of Ang-2 protein in plasma was significantly higher in LPS groups, but weak in control group. Compared with 2 mg/kg LPS group, the expression of Ang-2 protein in 4 mg/kg LPS group was significantly higher. While the expression of Ang-2 protein in 8 mg/kg LPS group was higher than those in other LPS groups.The expression of Ang-2 protein in plasma were significantly positively correlated with the pathological score (r=0.862, P0.05).Ang-2 could participate the pathological course in the rats model of LPS-induced acute lung injury. The expression of Ang-2 protein in serum was significantly positively correlated with the extent lung injury.