Integrated genome-wide association and transcriptomic analysis to identify receptor kinase genes to stripe rust resistance in wheat germplasm from southwestern China.

Stripe rust of wheat, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases of wheat worldwide. Identification of new and elite Pst-resistance loci or genes has the potential to enhance overall resistance to this pathogen. Here, we conducted an integrated genome-wide association study (GWAS) and transcriptomic analysis to screen for loci associated with resistance to stripe rust in 335 accessions from Yunnan, including 311 landraces and 24 cultivars. Based on the environmental phenotype, we identified 113 protein kinases significantly associated with Pst resistance using mixed linear model (MLM) and generalized linear model (GLM) models. Transcriptomic analysis revealed that 52 of 113 protein kinases identified by GWAS were up and down regulated in response to Pst infection. Among these genes, a total of 15 receptor kinase genes were identified associated with Pst resistance. 11 candidate genes were newly discovered in Yunnan wheat germplasm. Our results revealed that resistance alleles to stripe rust were accumulated in Yunnan wheat germplasm, implying direct or indirect selection for improving stripe rust resistance in elite wheat breeding programs.

Enhancing AsH3 Detoxification via Electron-Deficient [NiIII-OH (µ-O)] in a Nickel-Modified NaY Zeolite: A Pathway toward As0 Products.

The transformation of toxic arsine (AsH3) gas into valuable elemental arsenic (As0) from industrial exhaust gases is important for achieving sustainable development goals. Although advanced arsenic removal catalysts can improve the removal efficiency of AsH3, toxic arsenic oxides generated during this process have not received adequate attention. In light of this, a novel approach for obtaining stable As0 products was proposed by performing controlled moderate oxidation. We designed a tailored Ni-based catalyst through an acid etching approach to alter interactions between Ni and NaY. As a result, the 1Ni/NaY-H catalyst yielded an unprecedented proportion of As0 as the major product (65%), which is superior to those of other reported catalysts that only produced arsenic oxides. Density functional theory calculations clarified that Ni species changed the electronic structure of oxygen atoms, and the formed [NiIII-OH (µ-O)] active centers facilitated the adsorption of AsH2*, AsH*, and As* reaction intermediates for As-H bond cleavage, thereby decreasing the direct reactivity of oxygen with the arsenic intermediates. This work presents pioneering insights into inhibiting excessive oxidation during AsH3 removal, demonstrating potential environmental applications for recovery of As0 from toxic AsH3.

Macrophages enhance cisplatin resistance in gastric cancer through the transfer of circTEX2.

Cisplatin-based chemotherapy is often used in advanced gastric cancer (GC) treatment, yet resistance to cisplatin may lead to treatment failure. Mechanisms underlying cisplatin resistance remain unclear. Recent evidence highlighted the role of macrophages in cancer chemoresistance. Macrophage-derived exosomes were shown to facilitate intercellular communication. Here, we investigated the cisplatin resistance mechanism based on macrophage-derived exosomes in gastric cancer. Cell growth and apoptosis detection experiments revealed that M2-polarized macrophages increased the resistance of GC cells to cisplatin. qRT-PCR, RNAase R assay, actinomycin D assay and cell nucleo-cytoplasmic separation experiments confirmed the existence of circTEX2 in macrophage cytoplasm, with a higher expression level in M2 macrophages than that in M1 macrophages. Further experiments showed that circTEX2 acted as microRNA sponges for miR-145 and regulated the expression of ATP Binding Cassette Subfamily C Member 1 (ABCC1). Inhibition of the circTEX2/miR-145/ABCC1 axis blocked the cisplatin resistance of gastric cancer induced by M2 macrophages, as evidenced by in vitro and in vivo experiments. In conclusion, our research suggests that the exosomal transfer of M2 macrophage-derived circTEX2 enhances cisplatin resistance in gastric cancer through miR-145/ABCC1. Additionally, communication between macrophages and cancer cells via exosomes may be a promising therapeutic target for the treatment of cisplatin-resistant gastric cancer.

Halothiobacillus diazotrophicus sp. nov., a chemolithoautotrophic sulphur-oxidizing and nitrogen-fixing bacterium isolated from freshwater.

A sulphur-oxidizing and nitrogen-fixing bacterium, designated strain LS2T, was isolated from freshwater collected from the Pearl River in Guangzhou, PR China. The strain was an obligate chemolithoautotroph, utilizing reduced sulphur compounds (sulphide, sulphite, elemental sulphur, thiosulphate and tetrathionate) as energy sources and electron donors. Diazotrophic growth of strain LS2T was observed at 15-40 °C, pH 5-9, with a NaCl concentration range of 0-0.68 mol l-1 and with oxygen content higher than 21 %. The major cellular fatty acids were summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c) and C16 : 0. The DNA G+C content of the complete genome sequence was 60.7 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain LS2T formed a lineage within the family Halothiobacillaceae, showing gene sequence identity of 96.8 % with its closest relative Halothiobacillus neapolitanus c2. The genome of strain LS2T contains multiple genes encoding sulphur-oxidizing enzymes that catalyse the oxidation of reduced sulphur compounds and an nif complex encoding enzymes for nitrogen fixation. In addition, the genome contains genes encoding cbb3-type cytochrome c oxidase, aa3-type cytochrome c oxidase, bd-type quinol oxidase and cytochrome o oxidase, which enable the survival strain LS2T under oxic and microaerophilic conditions. On the basis of phenotypic, genotypic and phylogenetic data, strain LS2T is considered to represent a novel species of the genus Halothiobacillus, for which the name Halothiobacillus diazotrophicus sp. nov. is proposed. The type strain is LS2T (=GDMCC 1.4095T=JCM 39442T).

Coordinated health effects attributable to particulate matter and other pollutants exposures in the North China Plain.

Hebei Province, located in the North China Plain (NCP) and encircling Beijing and Tianjin, has been suffering from severe air pollution. The monthly average fine particulate matter (PM2.5) concentration was up to 276 µg/m3 in Hebei Province, which adversely affects human health. However, few studies evaluated the coordinated health impact of exposure to PM (PM2.5 and PM10) and other key air pollutants (SO2, NO2, CO, and surface ozone (O3)). In this study, we systematically analyzed the health risks (both mortality and morbidity) due to multiple air pollutants exposures in Hebei Province. The economic loss associated with these health consequences was estimated using the value of statistical life (VSL) and cost of illness (COI) methods. Our results show the health burden and economic loss attributable to multiple ambient air pollutants exposures in Hebei Province is substantial. In 2017, the total premature mortality from multiple air pollutants exposures in Hebei Province was 69,833 (95% CI: 55,549-83,028), which was 2.9 times higher than that of the Pearl River Delta region (PRD). Most of the potential economic loss (79.65%) was attributable to premature mortality from air pollution. The total economic loss due to the health consequences of multiple air pollutants exposures was 175.16 (95% CI: 134.61-224.61) billion Chinese Yuan (CNY), which was 4.92% of Hebei Province's annual gross domestic product (GDP). Thus, the adverse health effects and economic loss caused by exposure to multiple air pollutants should be seriously taken into consideration. To alleviate these damages, Hebei's government ought to establish more stringent measures and regulations to better control air pollution.

Parasulfuritortus cantonensis gen. nov., sp. nov., a microaerophilic sulfur-oxidizing bacterium isolated from freshwater sediment.

A novel sulfur-oxidizing bacterium, designated strain LSR1T, was enriched and isolated from a freshwater sediment sample collected from the Pearl River in Guangzhou, PR China. The strain was an obligate chemolithoautotroph, using thiosulfate or sulfide as an electron donor and energy source. Growth of strain LSR1T was observed at 15-40 °C, pH 6.0-7.5 and NaCl concentrations of 0-1.5 %. Strain LSR1T was microaerophilic, with growth only at oxygen content less than 10 %. Anaerobic growth was also observed when using nitrate as the sole electron acceptor. The major cellular fatty acids were C16 : 0 and summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c). The DNA G+C content of the draft genome sequence was 67.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain LSR1T formed a lineage within the family Thiobacillaceae, showing sequence identities of 92.87, 92.33 and 90.80 % with its closest relative genera Sulfuritortus, Annwoodia and Thiobacillus, respectively. The genome of strain LSR1T contained multiple genes encoding sulfur-oxidizing enzymes that catalyse thiosulfate and sulfide oxidation, and the gene encoding cbb 3-type cytochrome c oxidase and bd-type quinol oxidase, which enables strain LSR1T to perform sulphur oxidation under microaerophilic conditions. On the basis of phenotypic, genotypic and phylogenetic results, strain LSR1T is considered to represent a novel species of a new genus Parasulfuritortus within the family Thiobacillaceae, for which the name Parasulfuritortus cantonensis gen. nov., sp. nov. is proposed. The type strain is LSR1T (=GDMCC 1.1549=JCM 33645).

Association of consciousness impairment and mortality in people with COVID-19.

BACKGROUND: To investigate the association between impairment of consciousness and risk of death in people with COVID-19. METHODS: In this multicentre retrospective study, we enrolled people with confirmed COVID-19 from 44 hospitals in Wuhan and Sichuan, China, between 18 January and 30 March 2020. We extracted demographics, clinical, laboratory data and consciousness level (as measured by the Glasgow Coma Scale (GCS) score) from medical records. We used Cox proportional hazards regression, structural equation modelling and survival time analysis to compare people with different progressions of impaired consciousness. RESULTS: We enrolled 1,143 people (average age 51.3 ± standard deviation 17.1-year-old; 50.3% males), of whom 76 died. Increased mortality risk was identified in people with GCS score between 9 and 14 (hazard ratio (HR) 46.76, p < .001) and below 9 (HR 65.86, p < .001). Pathway analysis suggested a significant direct association between consciousness level and death. Other factors, including age, oxygen saturation level and pH, had indirect associations with death mediated by GCS scores. People who developed impaired consciousness more rapidly either from symptoms onset (<10 days vs. 10-19 days, p = .025, <10 days vs. ≥20 days and 10-19 days vs. ≥20 days, <.001) or deterioration of oxygen saturation (≤2 days vs.>2 days, p = .028) had shorter survival times. CONCLUSION: Altered consciousness and its progression had a direct link with death in COVID-19. Interactions with age, oxygen saturation level and pH suggest possible pathophysiology. Further work to confirm these findings explore prevention strategies and interventions to decrease mortality is warranted.

Sophoridine exerts tumor-suppressive activities via promoting ESRRG-mediated ß-catenin degradation in gastric cancer.

BACKGROUND: As a natural alkaloid product isolated from Sophora alopecuroides. L, Sophoridine reshapes gastric cancer immune microenvironment via inhibiting chemotaxis and M2 polarization of tumor-associated macrophages (TAMs). However, the exact effects and underlying mechanism of Sophoridine on gastric cancer cells remains poorly known. METHODS: The potential anti-tumor effects of Sophoridine on gastric cancer cell lines, including AGS and SGC7901 cells, were detected by CCK-8, EDU and colony forming assay, immunofluorescence, transwell assay, and flow cytometry. Molecular mechanisms of Sophoridine were investigated by siRNA transfection, nuclear/cytoplasmic extraction and western blot. The synergistic effects of Sophoridine with cisplatin on gastric cancer cells were further investigated in in vitro functional studies. RESULTS: Sophoridine exhibited potent tumor-suppressive activities in gastric cancer cells, including inhibition of proliferation, colony formulation, migration and invasion, as well as induction of apoptosis. In addition, we further showed that Sophoridine induced G2/M cell cycle arrest via inhibiting double-stranded DNA breaks repair and enhanced the efficacy of cisplatin in gastric cancer cells. Molecular studies further revealed that Sophoridine promoted ß-catenin degradation by enhancing Estrogen-related receptor gamma (ESRRG) expression, but not depended on ubiquitination-proteasome pathway, either TRIM33-mediated (GSK3ß-independent) or altered GSK3ß activity, and thus exerted potent tumor-suppressive activities. CONCLUSION: Sophoridine depends on targeting ESRRG/ß-catenin pathway to exert tumor-suppressive activities in gastric cancer cells and enhances the anti-tumor effect of cisplatin. Our study provided the promising preclinical anti-tumor evidence for the potential application of Sophoridine against gastric cancer.

New onset acute symptomatic seizure and risk factors in coronavirus disease 2019: A retrospective multicenter study.

Our aim was to clarify the incidence and risk of acute symptomatic seizures in people with coronavirus disease 2019 (COVID-19). This multicenter retrospective study enrolled people with COVID-19 from January 18 to February 18, 2020 at 42 government-designated hospitals in Hubei province, the epicenter of the epidemic in China; Sichuan province; and Chongqing municipality. Data were collected from medical records by 11 neurologists using a standard case report form. A total of 304 people were enrolled, of whom 108 had a severe condition. None in this cohort had a known history of epilepsy. Neither acute symptomatic seizures nor status epilepticus was observed. Two people had seizurelike symptoms during hospitalization due to acute stress reaction and hypocalcemia, and 84 (27%) had brain insults or metabolic imbalances during the disease course known to increase the risk of seizures. There was no evidence suggesting an additional risk of acute symptomatic seizures in people with COVID-19. Neither the virus nor potential risk factors for seizures seem to be significant risks for the occurrence of acute symptomatic seizures in COVID-19.

Insight into the diversity of antibiotic resistance genes in the intestinal bacteria of shrimp Penaeus vannamei by culture-dependent and independent approaches.

Antibiotic resistance genes (ARGs) that distributed in antibiotic resistant bacteria (ARBs) are widespread in aquaculture and have great threats to the aquatic organism as well as to human. However, our understanding about the risk of ARGs to the health of aquatic organism is still limited. In the present study, we got a deep insight into the diversity of ARGs in the intestinal bacteria of shrimp by culture-dependent and independent approaches. Results of the PCR-based detection and culture-dependent analysis indicated that the tetracycline, sulfadiazine, quinolone and erythromycin resistance genes were prevalent in the commercial shrimps that bought from aquatic markets or supermarket. The culture-independent plasmid metagenomic analysis identified 62 different ARGs, which were classified into 21 types, with abundances ranging from 13 to 1418 ppm. The analysis suggested that most of the ARGs come from the plasmids originating from Vibrio (accounted for 2.8-51%) and Aeromonas (accounted for 16-55%), and the Vibrio group was concluded to be the main bacterial pathogen that probably resulted in the shrimp disease. Accordingly, the plasmid metagenomic that focuses on the mobile genetic elements has great potential on the identification of ARGs in complex environments.

[Diversity of thaumarchaeal nitrite reductase (nirK) -like genes in environments].

OBJECTIVE: Nitrite reductase encoded by nirK is a key enzyme to denitrification, and is found in ammonia-oxidizing archaea (AOA). Based on the diversity of nirK, it was good to study the functions of nitrite reductase to AOA on denitrification. METHODS: We constructed nirK gene clone libraries based on the nirK gene PCR products of water, sediment and soil, screened the positive clones by restriction fragment length polymorphism ( RFLP), and sequenced the representative fragments from positive clones. RESULTS: RFLP analysis of the clone libraries shows that there were 10 OTUs in fresh water and sediment, 8 in vegetable soil and its nearby water. Phylogenetic analysis indicated that the amino acid sequences of these nirK were most closely related to the Candidatus Nitrosopumilus koreensis AR1 and Nitrosopumilus maritimus SCM1 with similarities ranging from 53% to 68%. Diversity index of clone libraries shows there were many different types of nirK genes in all samples. Diversity and evenness index of nirK gene of water samples was higher than soil samples whreas vegetable field samples were the richest. CONCLUSION: Thaumarchaeote nirK gene had high diversity in soil and freshwater environments which were very different from ocean sample. The nirK gene encoding nitrite reductase might be important for thaumarchaeote denitrification.

Urea Fertilization Significantly Promotes Nitrous Oxide Emissions from Agricultural Soils and Is Attributed to the Short-Term Suppression of Nitrite-Oxidizing Bacteria during Urea Hydrolysis.

The application of urea in agricultural soil significantly boosts nitrous oxide (N2O) emissions. However, the reason for nitrite accumulation, the period of nitrite-oxidizing bacteria (NOB) suppression, and the main NOB species for nitrite removal behind urea fertilization have not been thoroughly investigated. In this study, four laboratory microcosm experiments were conducted to simulate urea fertilization in agricultural soils. We found that within 36 h of urea application, nitrite oxidation lagged behind ammonia oxidation, leading to nitrite accumulation and increased N2O emissions. However, after 36 h, NOB activity recovered and then removed nitrite, leading to reduced N2O emissions. Urea use resulted in an N2O emission rate tenfold higher than ammonium. During incubation, Nitrobacter-affiliated NOB growth decreased initially but increased later with urea use, while Nitrospira-affiliated NOB appeared unaffected. Chlorate suppression of NOB lasted longer, increasing N2O emissions. Urease inhibitors effectively reduced N2O emissions by slowing urea hydrolysis and limiting free ammonia production, preventing short-term NOB suppression. In summary, short-term NOB suppression during urea hydrolysis played a crucial role in increasing N2O emissions from agricultural soils. These findings revealed the reasons behind the surge in N2O emissions caused by extensive urea application and provided guidance for reducing N2O emissions in agricultural production processes.

Sealing solid agar in serum bottles for rapid isolation and long-term preservation of chemoautotrophic ammonia-oxidizing bacteria.

Ammonia-oxidizing bacteria (AOB) are ubiquitous on the earth and have broad applications in bioremediation. However, the number of their species with standing in nomenclature and deposited in Microbial Culture Collections still remains low. Moreover, only a few novel species have been reported over the last decades. In this study, we sealed agar in serum bottles to develop a kind of solid agar plate with the oxygen concentration in the headspace maintained at low levels. By using these plates, eight AOB isolates including two novel species were obtained. When AOB cells were grown on the sealed solid agar plates, the time to form visible colonies was largely reduced and the maximum diameter of colonies reached 2 mm, which makes the process of AOB isolation rapid and efficient. Based on five AOB isolates, the headspace oxygen concentration had a significant influence on AOB growth either on solid plate or in liquid culture. Especially, when grown under 21 % O2, the number of colonies formed on solid agar plates was very low and sometimes no visible colony formed. Besides the application on AOB isolation, the sealed solid agar plate was also effective for the enumeration and preservation of AOB cells. When preserved under room temperature for more than ten months, the AOB colonies on the plate could still be recovered. This method provides a feasible way to isolate more novel AOB species from the environment and deposit more species in Microbial Culture Collections.

Enrichment, isolation and identification of sulfur-oxidizing bacteria from sulfide removing bioreactor.

Sulfur-oxidizing bacteria (SOB) are the main microorganisms that participate in the natural sulfur cycle. To obtain SOB with high sulfur-oxidizing ability under aerobic or anaerobic conditions, aerobic and anaerobic enrichments were carried out. Denaturing gradient gel electrophoresis (DGGE) profiles showed that the microbial community changed according to the thiosulfate utilization during enrichments, and Rhodopseudomonas and Halothiobacillus were the predominant bacteria in anaerobic enrichment and aerobic enrichment, respectively, which mainly contributed to the thiosulfate oxidization in the enrichments. Based on the enriched cultures, six isolates were isolated from the aerobic enrichment and four isolates were obtained from the anaerobic enrichment. Phylogenetic analysis suggested the 16S rRNA gene of isolates belonged to the genus Acinetobacter, Rhodopseudomonas, Pseudomonas, Halothiobacillus, Ochrobactrum, Paracoccus, Thiobacillus, and Alcaligenes, respectively. The tests suggested isolates related to Halothiobacillus and Rhodopseudomonas had the highest thiosulfate oxidizing ability under aerobic or anaerobic conditions, respectively; Paracoccus and Alcaligenes could aerobically and anaerobically oxidize thiosulfate. Based on the DGGE and thiosulfate oxidizing ability analysis, Rhodopseudomonas and Halothiobacillus were found to be the main SOB in the sulfide-removing reactor, and were responsible for the sulfur-oxidizing in the treatment system.

Sulfur dots and iron co-doped nickel-based metal-organic frameworks with high nanozyme activity for the colorimetric determination of α-glucosidase activity.

Alpha-glucosidase (α-Glu) plays a crucial role in regulating the normal physiological function of the body; therefore, α-Glu activity detection is crucial in clinical studies. In this study, a nickel-based metal-organic framework (Ni-MOF) co-doped with sulfur dots (SDs) and iron (Fe) was designed and constructed for the colorimetric detection of α-Glu. The SDs/Fe/Ni-MOF shows a very low Michaelis-Menten constant (0.0466 mM) for H2O2, suggesting a very high affinity for H2O2. Additionally, the free radicals generated by the nanozyme-catalyzed reaction were analyzed, and the feasibility of the nanozyme-catalyzed process was further verified using density functional theory. The bimetallic (Fe and Ni) can improve the catalytic activity of the material, and sulfur can improve the affinity with the substrate to further enhance the catalytic performance. Notably, hydroquinone (HQ) inhibits nanozyme activity, whereas α-Glu hydrolyzes alpha-arbutin (α-Arb) and subsequently produces HQ. Therefore, this study developed a method for detecting α-Glu activity using α-Arb as a substrate. This method has high selectivity, a wide detection range (1.00-100 U L-1), and a low detection limit (0.525 U L-1). Finally, the method was used to α-Glu activity detected in serum samples with good accuracy. This study provides a new method for the detection of α-Glu.

CircSOD2 polarizes macrophages towards the M1 phenotype to alleviate cisplatin resistance in gastric cancer cells by targeting the miR-1296/STAT1 axis.

Cisplatin is the first-line drug for gastric cancer (GC). Cisplatin resistance is the most important cause of poor prognosis for GC. Increasing evidence has identified the important role of macrophage polarization in chemoresistance. CircRNAs are newly discovered non-coding RNAs, characterized by covalently closed loops with high stability. Previous studies have reported a significant difference between circRNA profiles expressed in classically activated M1 macrophages, and those expressed in alternatively activated M2 macrophages. However, the underlying mechanism behind the regulation of GC cisplatin resistance by macrophages remains unclear. In our study, we observed the aberrant high expression of circSOD2 in M1 macrophages derived from THP-1. These expression patterns were confirmed in macrophages from patients with GC. Detection of the M1 and M2 markers confirmed that overexpression of circSOD2 enhances M1 polarization. The viability of cisplatin-treated GC cells was significantly reduced in the presence of macrophages overexpressing circSOD2, and cisplatin-induced apoptosis increased dramatically. In vivo experiments showed that macrophages expressing circSOD2 enhanced the effect of cisplatin. Moreover, we demonstrated that circSOD2 acts as a microRNA sponge for miR-1296 and regulates the expression of its target gene STAT1 (signal transducer and activator of transcription 1). CircSOD2 exerts its function through the miR-1296/STAT1 axis. Inhibition of circSOD2/miR-1296/STAT1 may therefore reduce M1 polarization. Overexpression of circSOD2 promotes the polarization of M1 macrophages and enhances the effect of cisplatin in GC. CircSOD2 is a novel positive regulator of M1 macrophages and may serve as a potential target for GC chemotherapy.

[Community structure of microbes involved in nitrification and denitrification in typical shrimp-farming water].

OBJECTIVE: We analyzed the community and diversity of microorganisms involved in nitrification and denitrification of nitrogen cycle in typical aquaculture water in order to manage microbiological degradation of NH4+ and NO2-, to control nitrogen pollution and nitrogen cycle in shrimp-farming water. METHODS: Samples were analyzed by Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) graph. We constructed clone libraries of the typical sample based on the functional gene ammonia monooxygenase gene (amoA), nitrite oxidoreductase gene (nxrA), and nitrite reductase gene (nirS). These three libraries were analyzed by using Restriction Fragment Length Polymorphism (RFLP). RESULTS: Phylogenetic analysis showed that all sequences from amoA library were clustered into beta-Proteobacteria, including Nitrosomonas (81%) and Nitrosospira (19%). Clones from nxrA library were clustered into alpha-Proteobacteria and delta-Proteobacteria, including Nitrobacter (92%) and Desulfobacteraceae (8%). Clones from nirS library were clustered into alpha-Proteobacteria, beta-Proteobacteria and Actinobacteria. Beta-Proteobacteria was the dominant group that consisted of Azoarcus (25%), Brachymonas (5%), and Thauera (20%). In alpha-Proteobacteria group, Sophophora (10%), Polymorphum (25%), Ruegeria (5%) were detected. In the Actinobacteria group, Streptomyces (10%) was detected. CONCLUSION: Microorganisms involved in nitrification and denitrification of nitrogen cycle were abundant. In the aquaculture water, Nitrosomonas was the main performer of ammoxidation, Nitrobacter was the main performer of nitrification, and many kinds of populations played important roles in the denitrification.

[Microbial community in nitrogen cycle of aquaculture water of the Pearl River Delta].

OBJECTIVE: In order to study the characteristic of nitrogen transport, the community structure and diversity of related microorganisms in aquaculture water of the Pearl River Delta. METHODS: We established an artificial aquaculture ecosystem to study the microbial community of 15N-stable isotope probing (15N-SIP) labeled nitrogen transport microorganisms. The 15N-labeled DNA was separated by CsCl-ethidium bromide density gradient centrifugation, and was used to construct 16S rRNA gene clone libraries of bacteria and archaea. RESULTS: Phylogenetic analysis shows that 19 Operational Taxonomic Units (OTUs) from bacterial library were clustered in Proteobacteria and Planctomycetes. Proteobacteria (99.2%) was the dominant group, mainly consisted of Comamonas (15.7%), Nitrosomonas (12.4%), Enterobacteriaceae (11.5%) and Nitrobacter (11.5%). From archaeal library 9 OTUs were divided into 3 phyla: Thaumarchaeota, Crenarchaeota and Euryarchaeota. CONCLUSION: We successfully elucidated the microbial community of nitrogen transport microorganisms in aquaculture water of Pearl River Delta by using 15N-SIP. The data of the community will provide essential information for isolating nitrogen degrading microorganism, and provide scientific basis for creating a healthy aquaculture environment.

BBOX1-AS1 contributes to colorectal cancer progression by sponging hsa-miR-361-3p and targeting SH2B1.

Colorectal cancer (CRC) is the third main cause of cancer-relevant deaths worldwide, and its incidence has increased in recent decades. Previous studies have indicated that certain long noncoding RNAs (lncRNAs) have regulatory roles in tumor occurrence and progression. Often, lncRNAs are competitive endogenous RNAs that sponge microRNAs to up-regulate mRNAs. Here, we examined the role of a novel lncRNA gamma-butyrobetaine hydroxylase 1 antisense RNA 1 (BBOX1-AS1) in CRC. We observed that BBOX1-AS1 is overexpressed in CRC cell lines, and BBOX1-AS1 knockdown enhances cell proliferation, migration and invasion while reducing cell apoptosis. miR-361-3p is present at a low level in CRC and is negatively modified by BBOX1-AS1. Moreover, miR-361-3p was validated to be targeted by BBOX1-AS1. Src homology 2 B adaptor protein 1 (SH2B1) was notably upregulated in CRC cell lines and was identified as a downstream gene of miR-361-3p. In addition, we found that miR-361-3p amplification can suppress the expression of SH2B1. Finally, data from rescue assays suggested that overexpression of SH2B1 counteracted BBOX1-AS1 silencing-mediated inhibition of CRC progression. In conclusion, BBOX1-AS1 promotes CRC progression by sponging hsa-miR-361-3p and up-regulating SH2B1.

Removal of Mg2+ inhibition benefited the growth and isolation of ammonia-oxidizing bacteria: An inspiration from bacterial interaction.

Ammonia-oxidizing bacteria (AOB) play an important role in the global nitrogen cycle and have broad applications in the nitrogen removal from wastewater. However, the AOB species are sensitive to environmental factors and usually form tight relationships with other microbes, making the AOB isolation and maintenance are difficult and time-consuming. In this study, the relationship that occurred between AOB and their bacterial partners was found to be able to improve the ammonia oxidation; during the co-cultivation, the magnesium ions (Mg2+) with removal rate as high as 36.7% was removed from culture medium by the concomitant bacterial species, which was regarded as the main reason for improving ammonia oxidation. During the pure cultivation of AOB isolate, when the concentration of Mg2+ reduced to low levels, the ammonia-oxidizing activity was more than 5 times and the amoA gene expression was more than 12 times higher than that grown in the initial culture medium. Based on a newly designed culture medium, the ammonia oxidation of AOB isolate grown in liquid culture was significantly promoted and the visible AOB colonies with much more number and larger diameter were observed to form on agar plates. With the addition of high concentration of calcium carbonate (CaCO3), AOB colonies could be easily and specifically identified by following the hydrolytic zones that formed around AOB colonies. Another AOB isolates were successively obtained from different samples and within a short time, suggesting the feasibility and effectivity of this culture medium and strategy on the AOB isolation from environments.