Multi-omics analysis reveals the collaboration and metabolisms of the anammox consortia driven by soluble/non-soluble Fe(III) as the sole iron element.

Iron is recognized as a physiological requirement for anammox bacteria (AnAOB), with Fe(II) considered to be the most effective form. However, Fe(III), instead of Fe(II) is the common iron form in natural and artificial ecosystems. In this study, the nitrogen removal performance and metabolic mechanisms in anammox consortia with soluble and non-soluble Fe(III) as the sole iron element were investigated. After the 150-day operation, the soluble (FeCl3) and insoluble (Fe2O3) Fe(III)-fed anammox systems reached nitrogen removal rates of 71.84 ± 0.80% and 50.20 ± 0.98%, respectively. AnAOB could survive with soluble (FeCl3) or insoluble (Fe2O3) Fe(III) as the sole iron element, reaching relative abundances of 18.49% and 13.16%, respectively. The results show that the formation of anammox core consortia can enable AnAOB's survival to adverse external conditions of Fe(II) deficiency. Metagenomic and metatranscriptomic analysis reveal that Ca. Kuenenia can only uptake Fe(II) into the cell for metabolisms either independently through the extracellular electron transfer or with the cross-feeding of symbiotic microbes. This study provides insight into the utilization and metabolic mechanisms of Fe(III) in Ca. Kuenenia-dominated consortia, and deepens the understanding of anammox core consortia in the nitrogen, carbon, and iron cycling, further promoting the practical applications of anammox processes.

Light-Driven Electron Uptake from Nonfermentative Organic Matter to Expedite Nitrogen Dissimilation by Chemolithotrophic Anammox Consortia.

Nonphotosynthetic microorganisms are typically unable to directly utilize light energy, but light might change the metabolic pathway of these bacteria indirectly by forming intermediates such as reactive oxygen species (ROS). This work investigated the role of light on nitrogen conversion by anaerobic ammonium oxidation (anammox) consortia. The results showed that high intensity light (>20000 lx) caused ca. 50% inhibition of anammox activity, and total ROS reached 167% at 60,000 lx. Surprisingly, 200 lx light was found to induce unexpected promotion of the nitrogen conversion rate, and ultraviolet light (<420 nm) was identified as the main contributor. Metagenomic and metatranscriptomic analyses revealed that the gene encoding cytochrome c peroxidase was highly expressed only under 200 lx light. 15N isotope tracing, gene abundance quantification, and external H2O2 addition experiments showed that photoinduced trace H2O2 triggered cytochrome c peroxidase expression to take up electrons from extracellular nonfermentative organics to synthesize NADH and ATP, thereby expediting nitrogen dissimulation of anammox consortia. External supplying reduced humic acid into a low-intensity light exposure system would result in a maximal 1.7-fold increase in the nitrogen conversion rate. These interesting findings may provide insight into the niche differentiation and widespread nature of anammox bacteria in natural ecotopes.

Synthesis of tetrasubstituted allenes via a 1,4-palladium migration/carbene insertion/ß-H elimination sequence.

A palladium-catalyzed synthesis of tetrasubstituted allenes from aryl bromides and aryl diazoacetates is developed. This transformation proceeded via an aryl to alkenyl 1,4-palladium migration/carbene insertion/ß-H elimination sequence under mild reaction conditions.

Microbial dynamics reveal the adaptation strategies of ecological niche in distinct anammox consortia under mainstream conditions.

The feasibility of anammox-based processes for nitrogen-contained wastewater treatment has been verified with different anammox bacteria, however, the ecological niche of anammox bacteria under mainstream conditions is still elusive. In this study, six sludge samples collected from different habitats were utilized to culture anammox bacteria under mainstream conditions, and two distinct anammox genera (Ca. Kuenenia and Ca. Brocadia) with a relative abundance of 6.31% (C1) and 3.09% (C3), respectively, were identified. Notably, the microbial dynamics revealed that anammox bacteria (AMX), ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB), Chloroflexi bacteria (CFX), and heterotrophic denitrification bacteria (HDB) were the core members in anammox consortia. However, Ca. Kuenenia and Ca. Brocadia occupied different ecological niches in anammox consortia. The dissolved oxygen and microbial structures of the anammox-continuous stirred tank reactor systems were the main factors to affect their niche differentiation. Meanwhile, comammox might exist in the systems and occupy the ecological niche of AOB in nitrogen cycling. The network analysis suggested that Ignavibacterium could be the associated bacteria in Ca. Kuenenia-dominated consortia, while Ca. Nitrotoga was that in the Ca. Brocadia-dominated consortia. Our findings reveal a valuable reference for the observation of distinct anammox genera under mainstream conditions, which provides theoretical guidance for the engineering application of mainstream anammox-based processes.

The organics-mediated microbial dynamics and mixotrophic metabolisms in anammox consortia under micro-aerobic conditions.

The engineering applications of mainstream anaerobic ammonium oxidation (anammox) have raised increasing attention due to its energy-efficient, however, the organics-mediated microbial dynamics and mixotrophic metabolisms in anammox consortia under micro-aerobic conditions are still elusive. Here, the response of the anammox process to sodium acetate and glucose at a C/N ratio ranging from 0 to 0.5 was investigated under micro-aerobic conditions, respectively. Results showed that the additional glucose could promote the nitrogen removal efficiency (NRE) and nitrogen removal rate (NRR) of anammox processes at a low C/N ratio (0.3), representing 84.00% and 0.53 N kg·m-3·d-1. The introduced organics could regulate the diversity of the microbial community and simplify the microbial relationship in anammox consortia. Anammox could not benefit from the introduced sodium acetate, while glucose could effectively enhance the anammox activity and microbial interactions in anammox consortia. Glucose might also stimulate the mixotrophic mechanism of Ca. Kuenenia, further promotes the proliferation of anammox sludge under micro-aerobic conditions. This study reveals that glucose could positively mediate microbial interactions and mixotrophic metabolism in anammox consortia under micro-aerobic conditions, which raises a new horizon for the proliferation of anammox sludge for mainstream engineering applications.

How anammox responds to the emerging contaminants: Status and mechanisms.

Numerous researches have been carried out to study the effects of emerging contaminants in wastewater, such as antibiotics, nanomaterials, heavy metals, and microplastics, on the anammox process. However, they are fragmented and difficult to provide a comprehensive understanding of their effects on reactor performance and the metabolic mechanisms in anammox bacteria. Therefore, this paper overviews the effects on anammox processes by the introduced emerging contaminants in the past years to fulfill such knowledge gaps that affect our perception of the inhibitory mechanisms and limit the optimization of the anammox process. In detail, their effects on anammox processes from the aspects of reactor performance, microbial community, antibiotic resistance genes (ARGs), and functional genes related to anammox and nitrogen transformation in anammox consortia are summarized. Furthermore, the metabolic mechanisms causing the cell death of anammox bacteria, such as induction of reactive oxygen species, limitation of substrates diffusion, and membrane binding are proposed. By offering this review, the remaining research gaps are identified, and the potential metabolic mechanisms in anammox consortia are highlighted.

[Application progress of proteomic in pharmacological study of Chinese medicinal formulae].

Chinese medicinal formulae are the important means of clinical treatment in traditional Chinese medicine. It is urgent to use modern advanced scientific and technological means to reveal the complicated mechanism of Chinese medicinal formulae because they have the function characteristics of multiple components, multiple targets and integrated regulation. The systematic and comprehensive research model of proteomic is in line with the function characteristics of Chinese medicinal formulae, and proteomic has been widely used in the study of pharmacological mechanism of Chinese medicinal formulae. The recent applications of proteomic in pharmacological study of Chinese medicinal formulae in anti-cardiovascular and cerebrovascular diseases, anti-liver disease, antidiabetic, anticancer, anti-rheumatoid arthritis and other diseases were reviewed in this paper, and then the future development direction of proteomic in pharmacological study of Chinese medicinal formulae was put forward. This review is to provide the ideas and method for proteomic research on function mechanism of Chinese medicinal formulae.

Deciphering behaviors of 6:2 chlorinated polyfluorinated ether sulfonate (alternative-PFOS) on anammox processes: Nitrogen removal efficiency and microbial adaptability.

This study investigates the behaviors and effects of F-53B, an alternative to perfluorooctane sulfonate on anaerobic ammonium oxidation (anammox) processes. Results showed that the nitrogen removal efficiency (NRE) reached 83.8 % at a F-53B concentration of 0.5 mg·L-1, while NRE decreased to 66.9 % with 5 mg·L-1 of F-53B. The defluorination rates of 17.8 % (0.5 mg·L-1) and 9.3 % (5 mg·L-1) were observed, respectively, suggesting the occurrence of F-53B degradation. The relative abundance of Ca. Kuenenia decreased from 26.1 % to 16.2 % with the F-53B concentration increasing from 0.5 mg·L-1 to 5 mg·L-1. Meanwhile, Denitratisoma was selectively enriched with a relative abundance of 40.7 % at an F-53B concentration of 0.5 mg·L-1. Ca. Kuenenia could reduce reactive oxygen species induced by F-53B to maintain the balance of oxidative stress. This study gains insight into the behaviors and metabolic mechanisms of F-53B in anammox consortia, suggesting the feasibility of anammox processes for industrial wastewater.

Microbial interactions play a keystone role in rapid anaerobic ammonium oxidation sludge proliferation and biofilm formation.

Two mature anaerobic ammonium oxidation (anammox) consortia with high/low relative abundance of anammox bacteria were inoculated for the rapid sludge proliferation and biofilm formation in this study, named up-flow anaerobic sludge blanket reactor (UASB1) (high) and UASB2 (low), respectively. Results showed that the nitrogen removal efficiency of UASB2 reached 90.94% after the 120-day operation, which was 13% higher than that of UASB1. Moreover, its biomass amounts were 22.18% (biofilm) and 40.96% (flocs) higher than that of UASB1, respectively. Ca. Kuenenia possessed relative abundances of 29.32% (flocs), 27.42% (biofilm) and 31.56% (flocs), 35.20% (biofilm) in the UASB1 and UASB2, respectively. The relative abundances of genes involved in anammox transformation (hzs, nir) and carbon metabolism (fdh, lgA/B/C, acs) were higher in the UASB2, indicating that Ca. Kuenenia might produce acetate and glycogen to enhance microbial interactions. These findings emphasized the importance of microbial interactions in anammox sludge proliferation and biofilm formation.

Coupling continuous poly(3-hydroxybutyrate) synthesis with piperazine-contained wastewater treatment: Fermentation performance and microbial contamination deciphering.

Open poly(3-hydroxybutyrate) (PHB) fermentation is of great potential, and batch PHB synthesis with piperazine as the nitrogen switch has been realized. However, it is vital to explore the feasibility of continuous PHB fermentation with piperazine-contained wastewater remediation collaboratively. Here, an aerobic membrane bioreactor was constructed for consecutive PHB synthesis. The removal efficiency of piperazine decreased from 100 % to 82.6 % after three cycles, meanwhile, the PHB concentration was 0.39 g·L-1, 0.18 g·L-1, and undetected for each cycle. Microbial community analysis showed that Proteobacteria, Actinobacteriota, and Bacteroidota were the main contaminating microbes. Furthermore, three metagenome-assembled genomes related to Flavobacterium collumnare, Herbaspirillum aquaticum, and Microbacterium enclense were identified as the dominant contaminating strains. These microbes obtained nitrogenous substrates transformed by Paracoccus sp. TOH, such as amino acids and dissolved organic matter, as nutrient for accumulation. This study verified the practicability of coupling continuous PHB synthesis with industrial wastewater treatment and revealed the derivation mechanism of contaminating species, which could provide a reference for the targeted nitrogen release gene knockout of functional PHB fermentation chassis.

Succession of microbial communities reveals the inevitability of anammox core in the development of anammox processes.

The lack of anammox seeds is regarded as the bottleneck of anammox-based processes. Although the interactions in anammox consortia have attracted increasing attention, little is known about the influence of inoculated sludge populations on the growth of anammox bacteria. In this study, four sludge of distinct communities mixed with anammox sludge (the relative abundance of Ca. Kuenenia was 1.96 %) were used as the seeds, respectively for the start-up of anammox processes. Notably, all these mixed microbial communities tend to form a similar microbial community, defined as the anammox core, containing anammox-bacteria (22.9 ± 5.9 %), ammonia-oxidizing-bacteria (0.8 ± 0.7 %), nitrite-oxidizing-bacteria (0.2 ± 0.2 %), Chloroflexi-bacteria (0.7 ± 0.4 %), and heterotrophic-denitrification-bacteria (0.3 ± 0.2 %). It also elucidated that the communities of Nitrosomonas-dominated sludge were the closest to the anammox core, and achieved the highest nitrogen-removal rate of 0.73 kg-N m-3 d-1. This study sheds light on the solution to the shortage of anammox seeds in the full-scale wastewater treatment application.

Biosynthesis of poly(3-hydroxybutyrate) by N,N-dimethylformamide degrading strain Paracoccus sp. PXZ: A strategy for resource utilization of pollutants.

N,N-dimethylformamide is a toxic chemical solvent, which widely exists in industrial wastewater. Nevertheless, the relevant methods merely achieved non-hazardous treatment of N,N-dimethylformamide. In this study, one efficient N,N-dimethylformamide degrading strain was isolated and developed for pollutant removal coupling with poly(3-hydroxybutyrate) (PHB) accumulation. The functional host was characterized as Paracoccus sp. PXZ, which could consume N,N-dimethylformamide as the nutrient substrate for cell reproduction. Whole-genome sequencing analysis confirmed that PXZ simultaneously possesses the essential genes for poly(3-hydroxybutyrate) synthesis. Subsequently, the approaches of nutrient supplementation and various physicochemical variables to strengthen poly(3-hydroxybutyrate) production were investigated. The optimal biopolymer concentration was 2.74 g·L-1 with a poly(3-hydroxybutyrate) proportion of 61%, showing a yield of 0.29 g-PHB·g-1-fructose. Furthermore, N,N-dimethylformamide served as the special nitrogen matter that could realize a similar poly(3-hydroxybutyrate) accumulation. This study provided a fermentation technology coupling with N,N-dimethylformamide degradation, offering a new strategy for resource utilization of specific pollutants and wastewater treatment.

[Silica induced α-SMA expression in HBE cell line by targeting the PI3K/Akt pathway].

OBJECTIVE: To explore the role of the phosphatidylinositol 3 kinase/protein kinase B (PI3K/Akt) pathway in silica-induced α-SMA (α smooth muscle actin) expression in HEB (human bronchial epithelial) cell. METHODS: The cultured HBE cells were divided into 5 groups: control, silica, PI3K inhibitor (Ly294002), both PI3K inhibitor (Ly294002) and silica at the same time and the inhibitor 24 h ahead of silica. The final concentrations of PI3K inhibitor and silica were 10 µmol/L and 100 µg/ml, respectively. Western blots were used to detect protein expressions of Akt, p-Akt, TGF-ß and α-SMA. The location and expression of α-SMA were measured by immunofluorescence assay. RESULTS: HBE cell line exposed to silica can induce Akt phosphorylation, in which expressions of p-Akt were up regulated 1 times at 48 and the highest at 72 h. The expressions of TGFß increased remarkably at 12 h and the peak at 48 h after silica exposure, while the expressions of α-SMA increased at 24 h and the highest at 72 h. However, the PI3K inhibitor (Ly294002) significantly down regulated α-SMA expression. When the cell line exposed to the PI3K inhibitor ahead of silica 24 h, the expressions of p-Akt and α-SMA were more remarkably down regulated which were decreased 1.5 times and 7.6 times respectively compare to silica exposure group. But no significant changes were found for TGFß expressions. The immunofluorescence assay showed that silica can induce α-SMA expression, which located in cytoplasma, and PI3K inhibitor can decrease the expression. CONCLUSIONS: Silica induced α-SMA expression in HBE cell line is by targeting the PI3K/Akt pathway and PI3K inhibitor can repress α-SMA expression.

[Annexin A5 gene polymorphism (-1C/T) and the susceptibility to pneumoconiosis in coal works].

OBJECTIVE: To explore the role of -1C/T single nucleotide polymorphism within Annexin A5 gene in the genetic susceptibility to coal worker's pneumoconiosis (CWP). METHODS: Four hundred and seventy CWP Han chinese patients and 428 Han chinese controls were enclosed in present case-control study. All subjects were exposed to coal dusts. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect the -1C/T SNP in Annexin A5 gene for all subjects. The relationship between the -1C/T SNP in Annexin A5 gene and CWP was analyzed. RESULTS: CT/TT genotype in -1C/T SNP was associated with a significantly decreased risk of CWP, as compared with the CC genotype among subgroups exposed to coal dusts for ≥ 27 years (adjusted OR = 0.65, 95%CI: 0.44 - 0.98, P = 0.039) and patients with CWP at stage II (adjusted OR = 0.55, 95%CI: 0.34 - 0.90, P = 0.028). CONCLUSION: The results of present study suggest that the Annexin A5 -1C/T polymorphism may be involved in the development of CWP in Han Chinese coal miners.

Palladium-catalyzed cross-coupling of unreactive C(sp3)-H bonds with azole C(sp2)-H bonds by using bromide as a traceless directing group.

A palladium-catalyzed intermolecular cross-coupling of unreactive C(sp3)-H bonds and azole C(sp2)-H bonds with bromide as a traceless directing group is described. The judicious selection of the bulky and electron-rich phosphine ligand is the key for the success of this cascade process. The protocol features a broad substrate scope, excellent regioselectivity, and good functional group tolerance.

Phosphorylation of C(sp3)-H Bonds via 1,4-Palladium Migration.

1,4-Palladium migration has emerged as a reliable method for directed C-H functionalization. In contrast to coupling with carbon nucleophiles, limited examples with heteroatom nucleophiles have been reported. Herein we report a palladium-catalyzed intermolecular C(sp3)-H phosphorylation reaction via 1,4-palladium migration, which is often difficult because of the strong coordination of phosphorus reagents to palladium catalysts. Phosphorylation of C(sp3)-H bonds is accomplished in good reaction yields with excellent regioselectivity. The judicious selection of the phosphine ligand proved to be the key to the success of this cascade process.

Bioconversion of waste activated sludge hydrolysate into polyhydroxyalkanoates using Paracoccus sp. TOH: Volatile fatty acids generation and fermentation strategy.

The expensive carbon matrix is a bottleneck restricting the industrialization of polyhydroxyalkanoates (PHAs). Volatile fatty acids (VFAs) derived from waste activated sludge via anaerobic fermentation might be alternative carbon matters for PHAs synthesis. In this study, the effect of enzymes on VFAs yields and the feasibility of the produced VFAs for PHAs fermentation by Paracoccus sp. TOH were investigated. The optimum cumulative VFAs concentration reached 4076.6 mg-COD·L-1 in the lysozyme treatment system. Correspondingly, the highest poly(3-hydroxybuturate-co-3-hydroxyvalerate) (PHBV) concentration (119.1 mg·L-1) containing 20.3 mol% 3-hydroxyvalerate was obtained. It proved that Paracoccus sp. TOH possesses the capability for PHBV accumulation. The functional hydrolytic-acidogenic microorganisms, such as Clostridium sensu stricto and Bacteroides sp. were accumulated. The functional genes encoding hydrolysis, carbohydrates metabolism, VFAs generation were enriched. This study offered a possible strategy for VFAs production and verified the feasibility of sludge hydrolysate as a high-quality carbon substrate for PHAs fermentation.

Nitrogen contribution and microbial community of size-fractionated anammox sludge in continuous stirred-tank reactors.

In this study, the microbial diversity of size-fractionated anammox sludge in a well-mixed system and their contribution to nitrogen transformation were investigated. Results showed that small granules (0.2-1.0 mm) contributed to the major part of the nitrogen removal rate (56 %) due to its largest mixed liquor volatile suspended solids (1240 ± 80 mg·L-1). However, large granules (>1.0 mm) possessed the highest relative abundances of Ca. Kuenenia stuttgartiensis and specific anammox activity, representing 49.34 % and 24.45 ± 0.01 mg-N·g-1-mixed liquor volatile suspended solids·h-1, respectively. The microbial diversity decreased as the increase of granular size, resulting in microbial community shifting to a simpler model. Metagenomic analysis showed that fine sludge might be the potential major for NO/N2O production in the mature well-mixed system under inorganic conditions. This study provides guidance for the evaluation of nitrogen contribution by anammox size-fractionated sludge and the inhibition of the potential NO/N2O emission in anammox processes.

[The analyses on dust pollution of one underground iron mine from 1991 to 2010].

OBJECTIVE: The main purpose of this work was to give the evidence of reasonable and feasible dust control measures which will be taken in the future by analyzing the trend of dust concentration from 1991 to 2010 and identifying working faces with the severe dust contamination in one underground iron mine. METHODS: The data was from routine monitoring between the years 1991 and 2010, which enclosed the total dust concentrations and silica contents. China National Standard of Occupational exposure limits for hazardous agents in the workplace used to judge whether the dust concentration exceeded the National Standard. RESULTS: The general trend of total dust concentration from 1991 to 2010 was decreased, especially maximum and average levels. The highest exceeding rate was 43.16% in 1993 and the best years were 2009 and 2010, but the exceeding rates were still over 30%. The dust exposure levels varied with different work faces. The mining and supporting were the most severe dust pollution faces which the highest ultra exceeding rates were 51.61% and 51.48% and the maximum exceeding times were 64.6 and 16.4 respectively. The next was constructing face with 40.23% exceeding rate and 24.6 times more than standard. CONCLUSION: The trend of total dust concentration from 1991 to 2010 was decreased, but the dust exceeding rate was still high. The strong measures should be taken to control the dust pollution in this iron mine, especially mining and supporting faces.

Evolution of microbial community and antibiotic resistance genes in anammox process stressed by oxytetracycline and copper.

The individual and combined impacts of copper ion (Cu2+) and oxytetracycline (OTC) on anaerobic ammonium oxidation (anammox) performance and its self-recovery process were examined. Experimental results showed that the anammox performance and activity of anammox bacteria were inhibited by 1.0 mg L-1 OTC, Cu2+ and OTC + Cu2+, and both single and combined inhibitions were reversible. The abundance of functional genes and parts of antibiotic resistance genes (ARGs) were positively related to the dominant bacterium Ca. Kuenenia, implying that the recovery of the performance was associated with the progressive induction of potentially resistant species after inhibition. The above outcomes illustrated that anammox bacteria were stressed by metals and antibiotics, but they still could remove nitrogen at a rate higher than 20.6 ± 0.8 kg N m-3 d-1, providing guidance for engineering applications of anammox processes.