Other polymerases have been "engineered" for particular properties by mutating specific functional sites so that, for example, dideoxyribonucleotides or ribonucleotides can be incorporated during the primer extension step.
www.genengnews.com Some examples of enzymes characterized in this way are: ribonucleotide reductase methane monooxygenase, tryptophan dioxygenase, deoxypusine hydroxylase, protocatechuate 2,3 dioxygenase, and cytochrome ba3.
en.wikipedia.org These ribonucleotide changes are likely to be harmful, as their ribose 2-hydroxyl group increases susceptibility of the adjacent phosphodiester bond to hydrolysis.
en.wikipedia.org To do this, they used genetic engineering to create a strain of mice whose cells produced higher-than-normal levels of an enzyme called ribonucleotide reductase.
www.washington.edu Hydrolysis of the phosphate bonds generates the ribonucleotide guanine mono-phosphate and a modified 2-pyridone.
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