Intelligent yeast strains with the ability to self-monitor the concentrations of intra- and extracellular phosphate or ammonium ion by emission of fluorescence from the cell surface.
Saccharomyces cerevisiae strains that respond to environmental changes and transmit the information by emission of fluorescence from the cell surface were constructed. The technique of cell surface engineering enabled the yeast cells to display enhanced cyan blue fluorescent protein (ECFP) or enhanced yellow fluorescent protein (EYFP) on the surface under the control of promoters that sense environmental changes. Two model promoters were examined in this study. For monitoring the intra- and extracellular concentrations of phosphate ion, the PHO5 promoter was chosen to display ECFP. The MEP2 promoter was used to display EYFP to sense the concentrations of ammonium ion. Fluorescence was observed by fluorescence microscopy and immunofluorescence microscopy, and the intensity was measured by a flow cytometer. The relationship between ion concentration inside and outside the cells was evaluated by the change in the rate of fluorescence. This S. cerevisiae system enables environmental changes to be transmitted as intra- and extracellular information using a suitable promoter functioning at real time and in a non-invasive manner.
Shibasaki
S
S
Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Japan.
Ninomiya
Y
Y
Ueda
M
M
Iwahashi
M
M
Katsuragi
T
T
Tani
Y
Y
Harashima
S
S
Tanaka
A
A
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D002462:Cell Membrane / Q000378:metabolism; D003470:Culture Media; D004926:Escherichia coli / Q000235:genetics; D005818:Genetic Engineering; D049452:Green Fluorescent Proteins; D007424:Intracellular Fluid / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008856:Microscopy, Fluorescence; D010710:Phosphates / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic; D000644:Quaternary Ammonium Compounds / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D003470:Culture Media; D008164:Luminescent Proteins; D010710:Phosphates; D000644:Quaternary Ammonium Compounds; D011994:Recombinant Proteins; C054562:yellow fluorescent protein, Bacteria; D049452:Green Fluorescent Proteins