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Your search keyword '"Hu, Chun"' showing total 13 results
Start Over Author "Hu, Chun" Publication Year Range Last 10 years Journal chemosphere
13 results on '"Hu, Chun"'

7. Identification of quorum sensing signal AHLs synthases in Candidatus Jettenia caeni and their roles in anammox activity

Author

Hu-Chun Tao, Tingting Zhu, Yongzhao Guo, Sitong Liu, and Xi Tang

Subjects
Environmental Engineering, Transcription, Genetic, Health, Toxicology and Mutagenesis, 0208 environmental biotechnology, Microbial Consortia, 02 engineering and technology, 010501 environmental sciences, Acyl-Butyrolactones, Wastewater, 01 natural sciences, Ligases, Bacterial Proteins, AHL synthase, Ammonium Compounds, Environmental Chemistry, Transcriptional expression, Gene, 0105 earth and related environmental sciences, ATP synthase, biology, Bacteria, Chemistry, Public Health, Environmental and Occupational Health, food and beverages, Quorum Sensing, General Medicine, General Chemistry, biochemical phenomena, metabolism, and nutrition, biology.organism_classification, Pollution, 020801 environmental engineering, Quorum sensing, Candidatus Jettenia caeni, Biodegradation, Environmental, Biochemistry, Anammox, biology.protein, Acyltransferases, Transcription Factors
Abstract

Acyl-homoserine lactone (AHL)-based quorum sensing (QS) in the anaerobic ammonium oxidizing (anammox) consortia has attracted increasing attention. However, AHL synthase in anammox bacteria and the relationship between AHL synthetic genes and anammox activity are still not clear because anammox bacteria have not been isolated from the consortia. Two novel synthases of AHLs (JqsI-1 and JqsI-2), which are HdtS-type rather than the widely studied LuxI-type, were identified in anammox bacteria Candidatus Jettenia caeni and synthesized four AHLs. There was a correlation between AHL concentration, in situ transcriptional expression of the AHL synthase genes (jqsI-1 and jqsI-2) and genetic marker of anammox activity (hydrazine synthase gene, hzsA). And AHL add-back studies demonstrated that AHL influence the expression of hzsA to regulate anammox bacterial activity. This study provides insight into the QS communication pathway of anammox bacteria for wastewater treatment.

Published
2018

8. Inhibitory effects of Skeletonema costatum on mercury methylation by Geobacter sulfurreducens PCA

Author

Shengchun Wu, Li-Juan Zhang, Ling-Yun Ding, Ming Hung Wong, Peng Liang, Sai Yang, Hu-Chun Tao, and Ning-Ning He

Subjects
Environmental Engineering, Health, Toxicology and Mutagenesis, 0208 environmental biotechnology, chemistry.chemical_element, Biological Availability, 02 engineering and technology, 010501 environmental sciences, Cyanobacteria, 01 natural sciences, Methylation, Algae, Environmental Chemistry, Biomass, Geobacter sulfurreducens, 0105 earth and related environmental sciences, Diatoms, biology, Public Health, Environmental and Occupational Health, General Medicine, General Chemistry, Mercury, Contamination, Methylmercury Compounds, biology.organism_classification, Pollution, 020801 environmental engineering, Mercury (element), Bioavailability, Diatom, chemistry, Environmental chemistry, Geobacter, Bacteria
Abstract

Algae and mercury (Hg) are ubiquitous in marine environments. In this study, we investigated the effects of a typical marine algae of diatom Skeletonema costatum on Hg methylation by an iron-reducing bacterium of Geobacter sulfurreducens (G. sulfurreducens) PCA. In the absence of Skeletonema costatum, the bacterial MeHg production rate maximized at 104.06 ± 11.7 ng L−1 h−1 with a high Hg level, while the highest methylation efficiency was achieved at a low Hg concentration. The existence of Skeletonema costatum greatly inhibited the capability of G. sulfurreducens PCA to methylate Hg. With the increase in algal biomass, there was a significant mitigation of MeHg formation and Hg0 release, leaving a considerable proportion of immobilized Hg2+ species (up to 47%) associated with algal cell materials. These results suggest that marine algae are crucial in determining the bioavailability of Hg contaminants and the methylating potential of G. sulfurreducens PCA.

Published
2018

12. Ubiquity of polystyrene digestion and biodegradation within yellow mealworms, larvae of Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae)

Author

Yang, Shan-Shan, primary, Wu, Wei-Min, additional, Brandon, Anja M., additional, Fan, Han-Qing, additional, Receveur, Joseph P., additional, Li, Yiran, additional, Wang, Zhi-Yue, additional, Fan, Rui, additional, McClellan, Rebecca L., additional, Gao, Shu-Hong, additional, Ning, Daliang, additional, Phillips, Debra H., additional, Peng, Bo-Yu, additional, Wang, Hongtao, additional, Cai, Shen-Yang, additional, Li, Ping, additional, Cai, Wei-Wei, additional, Ding, Ling-Yun, additional, Yang, Jun, additional, Zheng, Min, additional, Ren, Jie, additional, Zhang, Ya-Lei, additional, Gao, Jie, additional, Xing, Defeng, additional, Ren, Nan-Qi, additional, Waymouth, Robert M., additional, Zhou, Jizhong, additional, Tao, Hu-Chun, additional, Picard, Christine J., additional, Benbow, Mark Eric, additional, and Criddle, Craig S., additional

Published
2018
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13. Construction of g-C 3 N 4 /WO 3 /MoS 2 ternary nanocomposite with enhanced charge separation and collection for efficient wastewater treatment under visible light.

Author

Beyhaqi A, Zeng Q, Chang S, Wang M, Taghi Azimi SM, and Hu C

Subjects
Benzhydryl Compounds isolation & purification, Catalysis, Disulfides, Light, Molybdenum, Oxides, Phenols isolation & purification, Tungsten, Water Pollutants, Chemical isolation & purification, Graphite chemistry, Nanocomposites chemistry, Nitrogen Compounds chemistry, Wastewater chemistry, Water Purification methods
Abstract

Graphitic carbon nitride (g-C 3 N 4 ) has enormous potentials for photocatalysis, yet it only possesses moderate activity because of excitonic effects and sluggish charge transfer. Here, we develop a novel two-dimensional g-C 3 N 4 /WO 3 /MoS 2 (CWM) ternary nanocomposite through a facile co-calcination and a hydrothermal process to reach a highly-efficient photocatalyst for organic pollutant elimination under visible light. The WO 3 and MoS 2 nanoparticles were dispersed on the ultra-thin g-C 3 N 4 nanosheets, in which the electronegative g-C 3 N 4 facilitates formation of oxygen vacancies in WO 3 . Compared to pure g-C 3 N 4 , WO 3 , and binary composites, CWM exhibited higher photocatalytic activities for various organic pollutants removal under visible light irradiation. For instance, the CWM showed a removal ratio of ∼99% for RhB after only 10 min irradiation of visible light (λ > 420 nm) and nearly 100% for ciprofloxacin after 2 h of operation. The results showed that OH radicals are the main active species for organic degradation, which suggests a direct Z-scheme heterojunction in CWM that improved spatial separation of charge carries. Furthermore, the collection of electrons is significantly enhanced by MoS 2 for oxygen reduction reaction, and the increased oxygen vacancies of WO 3 further enhanced the separation of electron-hole pairs; therefore, it led to an effective suppression of charge carriers recombination. The above synergistic effects of ternary photocatalyst result in higher photocatalytic oxidation performance for wastewater treatment compared with pure WO 3 , g-C 3 N 4 and their binary composites., (Copyright © 2019. Published by Elsevier Ltd.)

Published
2020
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