Patent ID: 7781189
Filing Date: 2010-08-24
Classification: C07K,C12N,C12P

Abstract:
1. A method of catalyzing transglycosylation reactions between a donor nucleoside and an acceptor base comprising culturing transformed Escherichia coil host cells, said host cells: (i) expressing 340-1040 times higher uridine phosphorylase activity, 120-200 times higher purine nucleoside phosphorylase activity, or both, than corresponding non-transformed E. coli host cells, and (ii) transformed with a plasmid expression vector, said plasmid expression vector comprising: a) a polynucleotide encoding a uridine phosphorylase (UdP) polypeptide, wherein said polynucleotide comprises the sequence of nucleotides 243 to 1021 of SEQ ID NO: 6, or a polynucleotide encoding a purine nucleotide phosphorylase (PNP) polypeptide, wherein said polynucleotide comprises the sequence of nucleotides 1037 to 1766 of SEQ ID NO: 6, or both of said polynucleotides encoding UdP and PNP polypeptides; and b) at least one polynucleotide encoding a tetracycline or kanamycin resistance protein or a combination of polynucleotides encoding tetracycline and kanamycin resistance proteins iii) mixing a cell paste, cell extract, or purified enzyme(s) from said transformed E. coli host cells with a nucleoside and acceptor base, wherein the cell paste, cell extract, or purified enzyme(s) comprises at least one of said UdP and PNP polypeptides, and iv) catalyzing transglycosylation reactions between the donor nucleoside and the acceptor base.