| 摘要 |
Polydesoxy-nucleotides, such as a double helix of alternating 2'-desoxy-adenosine-5'- mono-phosphate, and thymine-5'- mono-phosphate (d(A-T)), are prepd. from 2'-desoxy-nucleotide-5- tri-phosphates using a DNA- polymerase having a free mercapto gp. external to its active centre. This enzyme is fixed by a covalent bond to a solid phase that is capable of linking through this mercapto gp. The prepn. is effected in the presence of divalent cations and opt. a prim. matrix complex, in a suitable buffered soln. at pH 6.5-9.5 and at 15-42 deg.C. - The prods. are used as models for a study of the physical, chemical, biochemical and biological properties of nucleic acids. The enzyme can be eliminated at the end of the reaction without losing its activity; it may therefore be used repeatedly and continuously. |
