A-YASHT for the detection of androgenic effects
The biological test system A-YASHT (Arxula-Yeast Androgen Screen for High Throughput-applications) is based on the use of androgen sensitive yeast, Arxula adeninivorans. The test was developed for parallel screening of large sample sizes, utilizing ready-to-use 384-well test plates and an optimized fluorescence reporter based on dsRED. The test can therefore be used in combination with automated liquid handling systems.
A-YASHT contains the growth medium and yeast mixed and lyophilized in every well. Only 40 µl of sample has to be added to each well. After 18 to 20 hours of incubation, the fluorescence (excitation 535 nm, emission 595 nm) can be measured directly. On request we offer individual configuration of the 384-well test plates for analyzing special test controls e. g. blanks (wells without yeast).
A-YASHT can be used for:
Determination of potential androgenic effects of drug candidates and new chemicals
Semi-quantitative analysis of ultrapure-, drinking- and mineral water
Semi-quantitative analysis of ground-, well- and surface water with low matrix effects
The test is not suitable for samples with high matrix load e. g. wastewater samples.
Response (Relative Fluorescence Units, RFU) of various androgens and androgen active substances analyzed with the A-YASHT.
|Duration of assay||ca. 26 h|
|Number of samples (DHTEQ)||max. 40|
|Calibration range *||0 – 360|
|Limit of detection*||31.3|
* ng/L 5α-Dihydrotestosterone (DHT)
The A-YASHT test is based on a genetically modified strain of the A. adeninivorans yeast which has been modified to bind with the human estrogen receptor, hAR. Binding of androgenic substances to the receptor subsequently activates production of a secretory reporter enzyme. The amount of enzyme activity correlates to the total concentration of androgenic substances in the sample. With the addition of the chromogenic substrate p-nitrophenyl phosphate, enzyme activity can be measured photometrically. 5α-Dihydrotestosterone (DHT) is used as a reference standard for calibration and quantification.
TEFp = translations elongations factor promotor / hAR = human androgen receptor gene/ GAAp = glucoamylase promotor / phyK = phytase reporter gene.