FIELD: medicine.
SUBSTANCE: method involves expression of recombinant membrane protein in E.coli cells as a part of a cytoplasmatic membrane. The spheroplast preparation is made of E.coli cells by permeabilisation of the cytoderm with using lysozyme, EDTA, MgCl2. A marked ligand is prepared; the spheroplasts are brought into the plate wells and incubated with the marked ligand. A membrane protein complex with the ligand on the spheroplast surface is detected. Then the fluorescence level is measured on the spheroplast surface by fluorescent microscopy method. The dissociation constants Kd are evaluated for the membrane protein complex with the ligand. It is followed with competitive replacement of fluorescence-marked ligand with an unmarked ligand from the membrane protein complex. The constants IC50 are evaluated for the unmarked ligand, and the dissociation constants Ki are calculated for the unmarked ligand.
EFFECT: invention allows simplifying the method and improving efficiency of qualitative and quantitative estimation of fixation of the membrane protein and the analysed compounds.
7 dwg, 2 ex
