The aim of this study was to investigate the potential application of the beta-d-glucuronidase (GLUase) activity measurement for the routine detection and quantification of E. coli in marine bathing waters. GLUase activity was measured as the rate of hydrolysis of 4-methylumbelliferyl-beta-d-glucuronide. Culturable E. coli were quantified by the most probable number (MPN) microplate method. Both methods were applied to a large set of seawater samples. Significant correlation was found between the log of GLUase activity and the log of culturable E. coli. The mean coefficient of variation (CV) of the GLUase activity was less than 15% at concentrations around the current standards of International regulations whereas the CV of the microplate method was around 30%. When samples were stored at 4 degrees C and 20 degrees C, the mean CV of the GLUase activity remained below 15% up to 6 hours after sample collection whereas the range of variation of the microplate method varied between 10 and 50%. We concluded that the GLUase activity is an operational, reproducible, simple, very rapid and low cost method for the real-time enumeration of E. coli in bathing waters and should be preferred to the microplate method. The GLUase activity method should be routinely applied to the rapid enumeration of E. coli in recreational waters and recommendations for its application were suggested to water quality managers.
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http://dx.doi.org/10.1016/j.marpolbul.2005.01.016 | DOI Listing |
Dev Comp Immunol
March 2022
Department of Cell and Molecular Biology, Uppsala University, Uppsala, The Biomedical Center, Box 596, SE-751 24, Uppsala, Sweden. Electronic address:
Granzyme B (GzmB) is primarily expressed by mammalian cytotoxic T cells and serves as one of the key components in the defense against viral infection by the induction of apoptosis in virus infected cells. By direct cell to cell contact and delivery into target cells by perforin, cytotoxic T cells activate apoptosis through the action of GzmB by both caspase-dependent and -independent pathways. In search for early ancestors of GzmB we have in the current study identified and characterized a GzmB homologue from a reptile, the Chinese alligator.
View Article and Find Full Text PDFJ Appl Microbiol
May 2019
State University of Paraíba, Campina Grande, PB, Brazil.
Aims: The aim of this study was to find new eukaryotic sources of the l-asparaginase (l-ASNase), since the prokaryotic sources of the enzyme are well-reported as causing allergic hypersensitivity reactions in a significant number of patients. This report describes screening for l-ASNase production by filamentous fungi isolated from the Brazilian Caatinga, and the optimization of fermentation parameters to increase fungal growth and improve yield in the production of l-ASNase.
Methods And Results: Thirty-two filamentous fungi were investigated in this study.
Anal Chim Acta
September 2015
INRA, UMR1347 Agroécologie, 17 Rue Sully, 21000 Dijon, France.
An assay on the indirect amperometric quantification of the β-D-Glucuronidase (GLUase) activity was developed for the rapid and specific detection of Escherichia coli (E. coli) in complex environmental samples. The p-aminophenyl β-D-glucopyranoside (PAPG) was selected as an electrochemical substrate for GLUase measurement and the p-aminophenol (PAP) released during the enzymatic hydrolysis was monitored by cyclic voltammetry with disposable carbon screen-printed sensors.
View Article and Find Full Text PDFJ Appl Microbiol
December 2009
UPMC Univ Paris 06, UMR7621, Laboratoire d'Océanographie Biologique de Banyuls, Observatoire Océanologique, Banyuls-sur-Mer, France.
Aims: To compare the Escherichia coli quantification given by the 'Coliplage' assay, based on the direct measurement of the beta-D-glucuronidase (GLUase) activity and the reference Most Probable Number (MPN) method from seawater sites and investigate the possible interference of non-E. coli strains in the GLUase activity measurement.
Methods And Results: Comparison performed from 69 French coastal bathing sites (1401 samples) showed nonconcordance between both methods, only for 8% of samples.
Curr Opin Biotechnol
June 2008
Department of Hydraulic and Environmental Engineering, Norwegian University of Science and Technology, SP Andersens vei 5, NO-7491 Trondheim, Norway.
Rapid enzyme assay techniques based on direct measurement of beta-d-galactosidase (GALase) or beta-d-glucuronidase (GLUase) activity without selective cultivation are used for rapid estimation of the level of coliform bacteria and Escherichia coli in water samples. Reported detection limits using fluorogenic substrates correspond to culturable target bacteria concentrations that can be appropriate within present guidelines for recreational waters. The rapidity, that is detection within one hour, compromises the specificity of the assay; enzyme activity contributions from other than target bacteria need to be considered, particularly at low levels of target bacteria.
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