A better method was screened out through comparison of the four methods for total DNA extraction of microorganisms with different lysis. The method screened out was used to optimize the experiments of treating filter membrane, DNA extraction and precipitation. Finally, the optimized method was compared with commercial kit for total DNA extraction of microorganisms. The results showed that the commercial kit was fit for total DNA extraction of microorganisms in surface snow on glacier, and another method with cutting the filter membrane into pieces, lysis (lysozyme (5 mg·mL-1) + proteaseK (1 mg·mL-1) +CTAB (1%)+SDS (1%)), extraction once by chloroform-isoamylalcohol (24:1) and DNA precipitation by ethanol, was an effective and low-cost method for total DNA extraction of microorganisms in surface snow on glacier.

　Agarose gel electrophoresis of PCR amplified 16S rDNA gene of bacteria from glacier surface snow by the three methods