| 摘要 |
PURPOSE:To obtain a heat-resistant DNA polymerase of higher thermal stability having residual activity of at least ca.60% by making a culture of a strain classified as Thermoascus and treating the resultant bacteria at 85 deg.C for 2hr at pH8.5. CONSTITUTION:A strain classified as Thermoascus such as Thermoascus thermophilus HB8 (ATCC 27634) is put to culture in a synthetic or natural medium at 50-80 deg.C and pH5-10 for 1-3 days by e.g., a shaking or aerated agitating culture to effect production and accumulation of heat-resistant DNA polymerate within the resultant bacterial Thence, the resultant enzyme is separated and purified using a general purification process followed by treatment at pH8.0 and 85 deg.C for 2hr to improve the heat resistance with its residual activity of at least 60%. The action of this enzyme is to catalyze the linkage of nucleotide-triphosphoric acid to form the nucleic acid chain complementary to the template chain of nucleic acid. Therefore, this enzyme can effectively be utilized in gene multiplication. |
