| 摘要 |
PROBLEM TO BE SOLVED: To provide the subject new DNA composed of a DNA coding for a protein having a specific amino acid sequence and heat-stable ribonuclease activity and usable e.g. for the production of the above enzyme useful as a reagent for genetic engineering, diagnosis of abnormality of gene, etc. SOLUTION: This new DNA codes for a protein composed of an amino acid sequence expressed by the formula or a protein composed of an amino acid sequence of the formula wherein one or several amino acids are depleted, substituted or added and having a heat-stable ribonuclease activity comparable to that of the protein of the formula. The DNA is useful e.g. for the production of a heat-stable ribonuclease for genetic engineering reagents such as a cycling probe reagent or diagnostic agents for the abnormality of gene, etc. The new DNA can be produced from ultra-high thermophilic archaebacteria Pyrococcus sp.KOD1 strain by the cloning by shot gun cloning method using a ribonuclease- dependent temperature-sensitive E.coli mutant as a host. |
