FIELD: biotechnology, genetic engineering. SUBSTANCE: for isolation of DNA preparations useful for polymerase chain reaction the analyzed sample (cells of yeast, fungi and gram-positive bacteria) are suspended in buffer solution containing chaotrop salt (guanidine thiocyanate or guanidine chloride), reducing agent of disulfide bonds (2-mercapto-ethanol), chelating agent (EDTA) and detergent (sarcosyl) taken in corresponding concentrations in the ratio of buffer solution to the volume of bacterial cells exceeding 5:1. Suspension is heated at water boiling point for 3-7 min, cells are precipitated by centrifugation, supernatant is discarded and precipitate containing genome DNA firmly associated with bacterial cellular envelopes is washed out with water twice and suspended in distilled water or in TE-buffer solution. Prepared suspension is used for polymerase chain reaction assay directly. EFFECT: simplified process, decreased cost and treatment time. 3 cl, 6 ex
