The development of a whole-cell fluorescence-based biosensor for nitrate is reported. The sensor is Escherichia coli transformed with a plasmid (pPNARGFP) in which the promoter and regulatory regions of the membrane-bound nitrate reductase narGHJI operon (Pnar) are fused to a gfp gene encoding green fluorescent protein (GFP). Pnar-gfp activity was measured at a range of nitrate concentrations using whole-cell GFP fluorescence. The bioassay conditions have been optimized so that the fluorescence intensity is proportional to the extracellular nitrate concentration. The developed bioassay has established that E. coli (pPNARGFP) can be used for the quantitative determination of nitrate in environmental waters without interference from other electron acceptors, e.g., nitrite, dimethyl sulfoxide, trimethylamine-N-oxide and fumerate, and azide, an inhibitor of redox-active proteins.
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http://dx.doi.org/10.1016/j.ab.2004.01.013 | DOI Listing |
Int J Cardiovasc Imaging
January 2025
Cardiology, Endeavor NorthShore Cardiovascular Institute, Evanston, IL, USA.
This study aims to evaluate the implementation of concomitant CAD assessment on pre-TAVI (transcatheter aortic valve implantation) planning CTA (CT angiography) aided by CT-FFR (CT-fractional flow reserve) [The CT2TAVI protocol] and investigates the incremental value of CT-FFR to coronary CT angiography (CCTA) alone in the evaluation of patients undergoing CT2TAVI. This is a prospective observational real-world cohort study at an academic health system on consecutive patients who underwent CTA for TAVI planning from 1/2021 to 6/2022. This represented a transition period in our health system, from not formally reporting CAD on pre-TAVI planning CTA (Group A) to routinely reporting CAD on pre-TAVI CTA (Group B; CT2TAVI protocol).
View Article and Find Full Text PDFAdv Biotechnol (Singap)
September 2024
College of Agronomy, Hunan Agricultural University, Changsha, 410128, China.
The use of nitrogen-fixing bacteria in agriculture is increasingly recognized as a sustainable method to boost crop yields, reduce chemical fertilizer use, and improve soil health. However, the microbial mechanisms by which inoculation with nitrogen-fixing bacteria enhance rice production remain unclear. In this study, rice seedlings were inoculated with the nitrogen-fixing bacterium R3 (Herbaspirillum) at the rhizosphere during the seedling stage in a pot experiment using paddy soil.
View Article and Find Full Text PDFAdv Biotechnol (Singap)
June 2024
Marine Synthetic Ecology Research Center, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Environmental Science and Engineering/Life Sciences/Ecology, Guangdong Provincial Observation and Research Station for Marine Ranching in Lingdingyang Bay, China-ASEAN Belt and Road Joint Laboratory On Mariculture Technology, State Key Laboratory for Biocontrol, Sun Yat-Sen University, Zhuhai, 519082, China.
Microorganisms in eutrophic water play a vital role in nitrogen (N) removal, which contributes significantly to the nutrient cycling and sustainability of eutrophic ecosystems. However, the mechanisms underlying the interactions and adaptation strategies of the N removal microorganisms in eutrophic ecosystems remain unclear. We thus analyzed field sediments collected from a eutrophic freshwater ecosystem, enriched the N removal microorganisms, examined their function and adaptability through amplicon, metagenome and metatranscriptome sequencing.
View Article and Find Full Text PDFCurr Microbiol
January 2025
Department of Plant Pathology, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, 641003, India.
Turmeric is affected by various phytopathogens, which cause huge economic losses to farmers. In the present study, ten isolates of Pythium spp. were isolated from infected turmeric rhizomes and characterized.
View Article and Find Full Text PDFEnviron Geochem Health
January 2025
The Fifth Prospecting Team of Shandong Coal Geology Bureau, Jinan, 250100, China.
Extensive agricultural regions commonly face issues of poor groundwater management, non-standard agricultural production practices, and unordered discharge of domestic pollution, leading to a continuous decline in groundwater quality and a sharp increase in risks. A comprehensive understanding of groundwater conditions and pollution is a crucial step in effectively addressing the water quality crisis. This study employs the Comprehensive Water Quality Index, Irrigation parameter, and Pollution Index to comprehensively investigate the groundwater quality in a typical agricultural area in Shandong, China, and assesses the suitability of groundwater for irrigation and the risks to human health.
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