Acetone-dried cells of amylase-producing bacteria were lysed by the action of the lysozyme at 37℃ for 22 hours in the presence of DNase inhibitor. Lysate was added into 2 volumes of alcohol and the precipitates formed were dissolved in 2 M NaCl solution. Proteins were removed by treating with chloroform and white fibrous precipitates were deposited with alcohol. These precipitates were dissolved in 10 % CaCl_2 and DNA fraction was precipitated by adding 0.3 volumes of alcohol. After centrifuging, alcohol was further added into supernatant to reach 2 volumes of original CaCl2 solution. Thus, white fibrous precipitates were formed. This preparation resembles DNA. However, it was found that the precipitate contained almost no DNA and that its solution has low viscosity and different UV spectrum from real DNA solution.
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