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In DNA replication, for example, formation of the phosphodiester bonds is catalyzed by a DNA polymerase enzyme, using a pair of magnesium cations and other supporting structures. [3] Formation of the bond occurs not only in DNA and RNA replication, but also in the repair and recombination of nucleic acids, and may require the involvement of ...
A phosphodiesterase (PDE) is an enzyme that breaks a phosphodiester bond. Usually, phosphodiesterase refers to cyclic nucleotide phosphodiesterases, which have great clinical significance and are described below.
DNA ligase is a type of enzyme that facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond.It plays a role in repairing single-strand breaks in duplex DNA in living organisms, but some forms (such as DNA ligase IV) may specifically repair double-strand breaks (i.e. a break in both complementary strands of DNA).
The DNase enzyme relies on the presence of a divalent cation, which is usually Ca 2+, for proper function. The active site of DNase I includes two histidine residues (His134 and His252) and two acidic residues (Glu78 and Asp 212), all of which are critical for the general acid-base catalysis of phosphodiester bonds. [10]
Although NPP primarily catalyzes phosphodiester hydrolysis, the enzyme will also catalyze the hydrolysis of phosphate monoesters, though to a much smaller extent. NPP preferentially hydrolyzes phosphate diesters over monoesters by factors of 10 2-10 6, depending on the identity of the diester substrate.
The mechanism of the ligation reaction was first elucidated in the laboratory of I. Robert Lehman. [4] [5] Two fragments of DNA may be joined by DNA ligase which catalyzes the formation of a phosphodiester bond between the 3'-hydroxyl group (-OH) at one end of a strand of DNA and the 5'-phosphate group (-PO4) of another.
In biochemistry, a ligase is an enzyme that can catalyze the joining of two molecules by forming a new chemical bond.This is typically via hydrolysis of a small pendant chemical group on one of the molecules, typically resulting in the formation of new C-O, C-S, or C-N bonds.
Deoxyribozymes, also called DNA enzymes, DNAzymes, or catalytic DNA, are DNA oligonucleotides that are capable of performing a specific chemical reaction, often but not always catalytic. This is similar to the action of other biological enzymes , such as proteins or ribozymes (enzymes composed of RNA ). [ 1 ]