EstraMonitor – A monitor for amperometric detection of estrogenic activity with Arxula adeninivorans yeast cells as the biocomponent

2012 ◽  
Vol 161 (1) ◽  
pp. 137-145 ◽  
Author(s):  
Ha Thi Minh Pham ◽  
Martin Giersberg ◽  
Steffen Uhlig ◽  
Gerold Hanke ◽  
Kirsten Simon ◽  
...  
Keyword(s):  
Estrogenic Activity ◽  
Amperometric Detection ◽  
Yeast Cells ◽  
Arxula Adeninivorans

Detection and removal of estrogencity in membrane biological reactors

2006 ◽  
Vol 6 (6) ◽  
pp. 19-26 ◽  
Author(s):  
J.Y. Hu ◽  
X. Chen
Keyword(s):  
Estrogenic Activity ◽  
Solid Phase ◽  
Treatment Plant ◽  
Endocrine Disrupting Compounds ◽  
Pilot Scale ◽  
Membrane Bioreactors ◽  
Yeast Cells ◽  
Endocrine Disrupting ◽  
And Behavior ◽  
Fate And Behavior

Three pilot-scale submerged membrane bioreactors (MBRs) in a local wastewater treatment plant (K, M and Z) were studied with the objective to compare the performance of pre-denitrification MBR systems in eliminating the estrogenic activity of the effluent of primary clarifier. A total of 5 batches of samples, which included influent, effluent, supernatant and sludge from the respective aerobic and anoxic tanks were collected over the span. They were investigated by using the developed solid-phase extraction (SPE) protocol coupled with a modified yeast-based estrogen screen (YES) assay. From the results, it could be seen that M MBR demonstrated the best endocrine disrupting compounds (EDCs) removal efficiency. The fate and behavior of EDCs in MBR systems were fairly understood with estrogenic activity formation dominating in the anoxic tank and removal dominating in the aerobic tank. It is believed that the sorption of EDCs onto the sludge as well as biodegradation of EDCs might be the key mechanisms for the EDCs removal. The low response of YES when dealing with influent samples was mainly due to the inhibition and antagonist effects induced by the influent samples on yeast cells.

Application of modified Arxula adeninivorans yeast cells in an online biosensor for the detection of estrogenic compounds in wastewater samples

2013 ◽  
Vol 185 ◽  
pp. 628-637 ◽  
Author(s):  
Ha Thi Minh Pham ◽  
Kirstin Kunath ◽  
Linda Gehrmann ◽  
Martin Giersberg ◽  
Jochen Tuerk ◽  
...  
Keyword(s):  
Yeast Cells ◽  
Arxula Adeninivorans ◽  
Estrogenic Compounds ◽  
Wastewater Samples

Detection of estrogenic activity in Flemish surface waters using an in vitro recombinant assay with yeast cells

2001 ◽  
Vol 43 (2) ◽  
pp. 117-123 ◽  
Author(s):  
H. E. Witters ◽  
C. Vangenechten ◽  
P. Berckmans
Keyword(s):  
Adverse Effects ◽  
Water Samples ◽  
Municipal Wastewater ◽  
Estrogenic Activity ◽  
Waste Water Treatment ◽  
Endocrine Disrupting Compounds ◽  
Environmental Chemicals ◽  
Yeast Cells ◽  
In Vivo Studies ◽  
Municipal Wastewater Treatment

Numerous environmental chemicals possess estrogen-like properties. At elevated doses, natural estrogens and environmental estrogen-like chemicals are known to produce adverse effects on humans and wildlife. Sources of potential exposure to endocrine disrupting compounds have to be identified for risk and hazard assessment. Extracts prepared from 16 selected water samples taken in Flemish rivers, effluents of municipal wastewater treatment plants and reservoirs for drinking water production were analysed for estrogenic activity with a cellular bioassay. Yeast cells, which are stably transfected with the DNA sequence of hER and which contain expression plasmids with the reporter gene lac-Z, encoding the enzyme b-galactosidase, were used to measure receptor binding. Flemish rivers showed the highest estrogenic potency, compared to effluents of waste water treatment plants and reservoirs which showed low induction factors (β-galactosidase production) relative to solvent control conditions. By comparison with a standard curve for 17β-estradiol (E2), estrogenic potency in water samples was calculated as E2-equivalents and ranged from below detection limit (˜ 2.75 ng E2/l) up to 81.4 ng/l E2-equivalents. About 7 water samples had more than 10 ng/l E2-equivalents. These elevated levels of E2-equivalents are likely to exert significant adverse effects on reproduction success of wildlife, which should be verified with in vivo studies.

Heterogeneity of Size and Distribution of Intramembrane Particles in the Plasma Membrane of Yeast

1977 ◽  
Vol 35 ◽  
pp. 596-597
Author(s):  
E. Keyhani
Keyword(s):  
Plasma Membrane ◽  
Candida Utilis ◽  
Synthetic Medium ◽  
Freeze Fracture ◽  
Translational Diffusion ◽  
Yeast Cells ◽  
Distilled Water ◽  
Intramembrane Particles ◽  
The Matrix ◽  
Water Cell

The matrix of biological membranes consists of a lipid bilayer into which proteins or protein aggregates are intercalated. Freeze-fracture techni- ques permit these proteins, perhaps in association with lipids, to be visualized in the hydrophobic regions of the membrane. Thus, numerous intramembrane particles (IMP) have been found on the fracture faces of membranes from a wide variety of cells (1-3). A recognized property of IMP is their tendency to form aggregates in response to changes in experi- mental conditions (4,5), perhaps as a result of translational diffusion through the viscous plane of the membrane. The purpose of this communica- tion is to describe the distribution and size of IMP in the plasma membrane of yeast (Candida utilis).Yeast cells (ATCC 8205) were grown in synthetic medium (6), and then harvested after 16 hours of culture, and washed twice in distilled water. Cell pellets were suspended in growth medium supplemented with 30% glycerol and incubated for 30 minutes at 0°C, centrifuged, and prepared for freeze-fracture, as described earlier (2,3).

Ultrathin frozen sections of yeast without aldehyde prefixation

1978 ◽  
Vol 36 (2) ◽  
pp. 58-59
Author(s):  
K. J. Böhm ◽  
a. E. Unger
Keyword(s):  
Aqueous Solutions ◽  
Biological Material ◽  
Yeast Cells ◽  
Frozen Sections ◽  
Good Preservation ◽  
Ultrathin Frozen Sections

During the last years it was shown that also by means of cryo-ultra-microtomy a good preservation of substructural details of biological material was possible. However the specimen generally was prefixed in these cases with aldehydes.Preparing ultrathin frozen sections of chemically non-prefixed material commonly was linked up to considerable technical and manual expense and the results were not always satisfying. Furthermore, it seems to be impossible to carry out cytochemical investigations by means of treating sections of unfixed biological material with aqueous solutions.We therefore tried to overcome these difficulties by preparing yeast cells (S. cerevisiae) in the following manner:

Deformation of Yeast Plasma Membrane by Ethidium Bromide

1988 ◽  
Vol 46 ◽  
pp. 254-255
Author(s):  
E. Keyhani
Keyword(s):  
Plasma Membrane ◽  
Thin Section ◽  
Ethidium Bromide ◽  
Freeze Fracture ◽  
Mutagenic Effect ◽  
Yeast Cells ◽  
Hydrophobic Region ◽  
Thin Section Electron Microscopy ◽  
Section Electron ◽  
Deep Pits

The mutagenic effect of ethidium bromide on the mitochondrial DNA is well established. Using thin section electron microscopy, it was shown that when yeast cells were grown in the presence of ethidium bromide, besides alterations in the mitochondria, the plasma membrane also showed alterations consisting of 75 to 110 nm-deep pits. Furthermore, ethidium bromide induced an increase in the length and number of endoplasmic reticulum and in the number of intracytoplasmic vesicles.Freeze-fracture, by splitting the hydrophobic region of the membrane, allows the visualization of the surface view of the membrane, and consequently, any alteration induced by ethidium bromide on the membrane can be better examined by this method than by the thin section method.Yeast cells, Candida utilis. were grown in the presence of 35 μM ethidium bromide. Cells were harvested and freeze-fractured according to the procedure previously described.

Three-Dimensional Immunoelectron Microscopy of Yeast Cells by a New High-Resolution Replica Method

1985 ◽  
Vol 43 ◽  
pp. 562-563
Author(s):  
Hirano T. ◽  
M. Yamaguchi ◽  
M. Hayashi ◽  
Y. Sekiguchi ◽  
A. Tanaka
Keyword(s):  
High Resolution ◽  
Plasma Polymerization ◽  
Three Dimensional ◽  
Freeze Fracture ◽  
Replica Method ◽  
Yeast Cells ◽  
Dynamic Aspect ◽  
Replica Technique ◽  
Gaseous Hydrocarbon ◽  
Transmission Electron

A plasma polymerization film replica method is a new high resolution replica technique devised by Tanaka et al. in 1978. It has been developed for investigation of the three dimensional ultrastructure in biological or nonbiological specimens with the transmission electron microscope. This method is based on direct observation of the single-stage replica film, which was obtained by directly coating on the specimen surface. A plasma polymerization film was deposited by gaseous hydrocarbon monomer in a glow discharge.The present study further developed the freeze fracture method by means of a plasma polymerization film produces a three dimensional replica of chemically untreated cells and provides a clear evidence of fine structure of the yeast plasma membrane, especially the dynamic aspect of the structure of invagination (Figure 1).

Sign in / Sign up

Export Citation Format

Share Document