Patent ID: 6329177
Filing Date: 2001-12-11
Classification: C07H,C12P,Y02P

Abstract:
A method for preparing nucleotide polymers having a defined monomer sequence by polymerization in the 3' to 5' direction, tbe method comprisinga) providing a primer of the general formula p(dNp).sub.m or p(rNp).sub.m and a carrier molecule of the general formula (rM).sub.n dN or (rM).sub.n dU-rN wherep is a phosphate group, a phosphorothioate group, a phosphonate group, a methyl-phosphonate group, a phosphoramidate group, a formylacetyl group, a phosphorodithioate group, a boranephosphate group, or a phosphotriester group;dN is a natural or modified deoxyribonucleoside;rN is a natural or modified ribonucleoside;m is an integer of 1 or more;rM is a purine or pyrimidine ribonucleoside;n is an integer of 1 or more; anddU is a deoxyuridine;b) ligating the 3' end of the carrier molecule to the 5' position of the primer with RNA ligase; thereby obtaining a ligation product;c) deprotecting the ligation product by removing (rM).sub.n when using a carrier molecule of the general formula (rM).sub.n dN or removing (rM).sub.n dU when using a carrier molecule of the general formula (rM).sub.n dU-rN;d) transferring a natural or modified phosphate group to the 5' position of the ligation product;e) optionally repeating steps (a) to (d); andf) optionally purifying the ligation product.