Plant biosensor
Dotaz
Zobrazit nápovědu
Plant hormones are a group of naturally occurring, low-abundance organic compounds that influence physiological processes in plants. Our knowledge of the distribution profiles of phytohormones in plant organs, tissues, and cells is still incomplete, but advances in mass spectrometry have enabled significant progress in tissue- and cell-type-specific analyses of phytohormones over the last decade. Mass spectrometry is able to simultaneously identify and quantify hormones and their related substances. Biosensors, on the other hand, offer continuous monitoring; can visualize local distributions and real-time quantification; and, in the case of genetically encoded biosensors, are noninvasive. Thus, biosensors offer additional, complementary technologies for determining temporal and spatial changes in phytohormone concentrations. In this review, we focus on recent advances in mass spectrometry-based quantification, describe monitoring systems based on biosensors, and discuss validations of the various methods before looking ahead at future developments for both approaches.
The principle of synchronous detection (SD) has been applied to biosensor measurement. SD principle achieves significant increases in the signal to noise ratio, limit of detection and overall measurement robustness. Application of SD in biosensor measurement improves the analysis of the response and avoids the influence of interference/noise produced by stirring, electromagnetic effects and influence of parasitic currents. SD also enables the decomposition of signal to stimulation response and phenomena with long time of response. Second-order phenomena are identifiable in the signal. Linear statistical model was used to develop software for identification of the stimulation signal in the output current. SD was applied to the response signal of a Photosystem II complex (PSII) biosensor. PSII response to light stimulation follows first order kinetics. The inhibition kinetics of PSII has been studied. Kinetic constants of herbicide binding to PSII depend linearly on herbicide concentration and enable measurement of its concentration at low concentrations (linear range for diuron is 10⁻⁶ to 10⁻⁴ mM).
- MeSH
- biosenzitivní techniky metody MeSH
- časové faktory MeSH
- enzymy imobilizované antagonisté a inhibitory metabolismus MeSH
- fotosystém II (proteinový komplex) antagonisté a inhibitory metabolismus MeSH
- inhibitory enzymů farmakologie MeSH
- kinetika MeSH
- Synechococcus enzymologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Although phosphatidic acid (PA) is structurally the simplest membrane phospholipid, it has been implicated in the regulation of many cellular events, including cytoskeletal dynamics, membrane trafficking and stress responses. Plant PA shows rapid turnover but the information about its spatio-temporal distribution in plant cells is missing. Here we demonstrate the use of a lipid biosensor that enables us to monitor PA dynamics in plant cells. The biosensor consists of a PA-binding domain of yeast SNARE Spo20p fused to fluorescent proteins. Live-cell imaging of PA dynamics in transiently transformed tobacco (Nicotiana tabacum) pollen tubes was performed using confocal laser scanning microscopy. In growing pollen tubes, PA shows distinct annulus-like fluorescence pattern in the plasma membrane behind the extreme tip. Coexpression studies with markers for other plasmalemma signaling lipids phosphatidylinositol 4,5-bisphosphate and diacylglycerol revealed limited colocalization at the shoulders of the apex. PA distribution and concentrations show distinct responses to various lipid signaling inhibitors. Fluorescence recovery after photobleaching (FRAP) analysis suggests high PA turnover in the plasma membrane. Our data show that a biosensor based on the Spo20p-PA binding domain is suitable for live-cell imaging of PA also in plant cells. In tobacco pollen tubes, distinct subapical PA maximum corroborates its involvement in the regulation of endocytosis and actin dynamics.
- MeSH
- biosenzitivní techniky metody MeSH
- buněčná membrána chemie metabolismus MeSH
- diglyceridy metabolismus MeSH
- fluorescence MeSH
- fosfatidylinositol-4,5-difosfát metabolismus MeSH
- fosfolipasa D metabolismus MeSH
- fotovybělování MeSH
- kyseliny fosfatidové analýza metabolismus MeSH
- počítačové zpracování obrazu MeSH
- proteiny Qb-SNARE genetika metabolismus MeSH
- proteiny Qc-SNARE genetika metabolismus MeSH
- pylová láčka genetika růst a vývoj metabolismus MeSH
- rekombinantní fúzní proteiny genetika metabolismus MeSH
- Saccharomyces cerevisiae - proteiny genetika metabolismus MeSH
- tabák cytologie metabolismus MeSH
- vazebná místa MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
We compared a novel PSII-biosensor assay with a standard algal growth inhibition test for detection of photosynthetic herbicides--diuron, atrazine and isoproturon in liquid samples. To evaluate the convenience and sensitivity, values of the parameters EC50 and LOD and the duration of assays were compared. The biosensor assay was made with an electrochemical biosensor toxicity analyser with immobilised Photosystem II (PSII) complex. Using the PSII-biosensor assay, higher sensitivity (LOD) to herbicides (10(-8)-10(-9)M) was achieved as compared to standard algal growth inhibition tests (about 10(-7)M). The results of both assays showed a good correlation as concerns their EC50 values while the interval of detectable concentrations is about twice wider for PSII-biosensor. A proposed measurement protocol includes the reference standard of phytotoxicity (RSP). The main advantage of the PSII-biosensor assay is that it can be completed in about 1h and is by 1-2 orders more sensitive than standard algal growth inhibition test, which takes 72 h.
- MeSH
- atrazin toxicita MeSH
- biosenzitivní techniky metody MeSH
- časové faktory MeSH
- chemické látky znečišťující vodu toxicita MeSH
- Chlorophyta účinky léků růst a vývoj metabolismus MeSH
- diuron toxicita MeSH
- fenylmočovinové sloučeniny toxicita MeSH
- fotosyntéza účinky léků MeSH
- fotosystém II (proteinový komplex) antagonisté a inhibitory metabolismus MeSH
- herbicidy toxicita MeSH
- reprodukovatelnost výsledků MeSH
- roztoky chemie MeSH
- senzitivita a specificita MeSH
- testy toxicity MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
The light-driven splitting of water to oxygen (O2) is catalyzed by a protein-bound tetra-manganese penta-oxygen calcium (Mn4O5Ca) cluster in Photosystem II. In the current study, we used a large-scale integration (LSI)-based amperometric sensor array system, designated Bio-LSI, to perform two-dimensional imaging of light-induced O2 evolution from spinach leaves. The employed Bio-LSI chip consists of 400 sensor electrodes with a pitch of 250 μm for fast electrochemical imaging. Spinach leaves were illuminated to varying intensities of white light (400-700 nm) which induced oxygen evolution and subsequent electrochemical images were collected using the Bio-LSI chip. Bio-LSI images clearly showed the dose-dependent effects of the light-induced oxygen release from spinach leaves which was then significantly suppressed in the presence of urea-type herbicide 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). Our results clearly suggest that light-induced oxygen evolution can be monitored using the chip and suggesting that the Bio-LSI is a promising tool for real-time imaging. To the best of our knowledge, this report is the first to describe electrochemical imaging of light-induced O2 evolution using LSI-based amperometric sensors in plants.
Confocal laser-scanning microscopy was chosen to observe the colonization and damage caused by the soft rot Pectobacterium atrosepticum and the protection mediated by the biocontrol agent Rhodococcus erythropolis. We developed dual-color reporter strains suited for monitoring quorum-sensing and quorum-quenching activities leading to maceration or biocontrol, respectively. A constitutively expressed cyan or red fluorescent protein served as a cell tag for plant colonization, while an inducible expression reporter system based on the green fluorescent protein gene enabled the simultaneous recording of signaling molecule production, detection, or degradation. The dual-colored pathogen and biocontrol strains were used to coinoculate potato tubers. At cellular quorum, images revealed a strong pectobacterial quorum-sensing activity, especially at the plant cell walls, as well as a concomitant rhodococcal quorum-quenching response, at both the single-cell and microcolony levels. The generated biosensors appear to be promising and complementary tools useful for molecular and cellular studies of bacterial communication and interference.
Inhibition of porcine pancreas and human saliva alpha-amylase (EC 3.2.1.1) by sanguinarine and chelerythrine was studied. The inhibition of alpha-amylase was assayed using a biosensor method which utilises a flow system equipped with a peroxide electrode. 250 microM sanguinarine and 250 microM chelerythrine cause complete inhibition of 1.9 nkat alpha-amylase from porcine pancreas. The same concentration of sanguinarine and chelerythrine caused 23.9% and 7.5% inhibition, respectively, of 1.9 nkat alpha-amylase from human saliva. Mixed type and partially reversible inhibition was found for both alpha-amylases treated with either alkaloid.
- MeSH
- alfa-amylasy antagonisté a inhibitory metabolismus MeSH
- alkaloidy farmakologie metabolismus MeSH
- biosenzitivní techniky MeSH
- časové faktory MeSH
- fenantridiny farmakologie metabolismus MeSH
- financování organizované MeSH
- inhibitory enzymů farmakologie MeSH
- kinetika MeSH
- lidé MeSH
- prasata MeSH
- stabilita enzymů MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
The prospective uses of tree gum polysaccharides and their nanostructures in various aspects of food, water, energy, biotechnology, environment and medicine industries, have garnered a great deal of attention recently. In addition to extensive applications of tree gums in food, there are substantial non-food applications of these commercial gums, which have gained widespread attention due to their availability, structural diversity and remarkable properties as 'green' bio-based renewable materials. Tree gums are obtainable as natural polysaccharides from various tree genera possessing exceptional properties, including their renewable, biocompatible, biodegradable, and non-toxic nature and their ability to undergo easy chemical modifications. This review focuses on non-food applications of several important commercially available gums (arabic, karaya, tragacanth, ghatti and kondagogu) for the greener synthesis and stabilization of metal/metal oxide NPs, production of electrospun fibers, environmental bioremediation, bio-catalysis, biosensors, coordination complexes of metal-hydrogels, and for antimicrobial and biomedical applications. Furthermore, polysaccharides acquired from botanical, seaweed, animal, and microbial origins are briefly compared with the characteristics of tree gum exudates.
- MeSH
- antiinfekční látky chemie metabolismus MeSH
- biodegradace MeSH
- biomedicínské technologie MeSH
- biosenzitivní techniky MeSH
- hydrogely metabolismus MeSH
- nanostruktury MeSH
- nanotechnologie * MeSH
- nanovlákna chemie MeSH
- polysacharidy metabolismus MeSH
- prospektivní studie MeSH
- rostlinné exsudáty chemie metabolismus MeSH
- rostlinné gumy chemie metabolismus MeSH
- stromy chemie metabolismus MeSH
- technologie zelené chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
This review summarizes achievements in electrochemistry-related research of steroid-based compounds in clinical, pharmaceutical, and environmental analysis. Special attention is paid to compounds possessing none or only isolated double bonds at the steroid core. Their direct redox activity is limited to far positive/negative potentials under variety of conditions and electrode materials and relies on the functional groups attached to the steroid skeleton, or as the case may be its double bond or moieties present at the side chain. The possibilities of electroanalytical methods in sterol characterization and analysis are demonstrated in a table with 31 references devoted to direct voltammetric and amperometric methods of oxidation of cholesterol, phytosterols, oxysterols, and related compounds at carbon-based and metal-based nanoparticles modified electrodes, and the reduction of bile acids and their conjugates at mercury-based electrodes, and modified glassy carbon electrodes. Furthermore, methods based on the indirect oxidation of cholesterol using bromine species as a mediator at platinum electrode and non-enzymatic cholesterol biosensors are reviewed. Their drawbacks and benefits are discussed with respect to the challenging task of identification and quantitation of these compounds in biological matrices, otherwise mostly performed using expensive mass spectrometric techniques preceded by a chromatographic separation step.
- MeSH
- biosenzitivní techniky přístrojové vybavení metody MeSH
- cholesterol analýza MeSH
- elektrochemické techniky přístrojové vybavení metody MeSH
- fytosteroly analýza MeSH
- lidé MeSH
- oxidace-redukce MeSH
- steroidy analýza MeSH
- žlučové kyseliny a soli analýza MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Outflows from secondary stages of conventional me-chanical-biological wastewater treatment plants (WWTPs) still contain significant concentrations of faecal pollution indicators suggesting the potential presence of pathogenic organisms. The decrease in the concentration of somatic coliphages and bacterial indicators of faecal pollution during the technological stages (coagulation, sand filtra-tion, membrane ultrafiltration, sorption on granular acti-vated carbon, disinfection, accumulation) of a semi-operational plant designed for multi-stage tertiary treat-ment or rather recycling of treated wastewater was moni-tored and discussed. During the tertiary treatment, faecal bacteria indicators were better removed than somatic coliphages, hence the inclusion of somatic indicators among faecal pollution indicators in water quality control for reuse is entirely appropriate. Subsequent tertiary treat-ment, including disinfection, is essential for safe reuse of treated water.
