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An enzyme that catalyzes the splitting of nucleic acids to nucleotides, nucleosides, or the components of the latter.



a phosphodiesterase enzyme that splits nucleic acids into mononucleotides and oligonucleotides.

Nucleases are widely distributed in the cells of microorganisms, plants, and animals. These enzymes are especially abundant in pancreatic juice and in the saliva of mammals and man. A distinction is made between 3′ and 5′ nucleases, depending on whether the enzyme splits the phosphodiester bonds of the nucleic acid to form nucleotides that contain phosphoric acid residues on the 3’- or 5’-carbon of the carbohydrate fragment. The terminal mononucleotides are separated by exonucleases; nucleases that split bonds within the polynucleotide chain are called endonucleases. Ribonucleases and deoxyribonucleases are distinguished according to whether they split ribonucleic or deoxyribonucleic acids. Nonspecific nucleases are able to split chains of both types of acids.

Nucleases are proteins—usually basic—with a comparatively low molecular weight; for example, the pancreatic ribonuclease molecule consists of 124 amino-acid residues. The biological function of nucleases is to digest and split nucleic acids that are foreign to the organism, for example, nucleic acids of invasive viruses. This is the rationale for using nucleases to treat certain viral diseases. Nucleases participate in the repair of deoxyribonucleic acid (DNA) by eliminating the fragmented portions of the DNA molecule from the polynucleotide chain. Nucleases also appear to play a major role in regulating the synthesis and decomposition of nucleic acids in cells. A nuclease enzyme can be used in laboratories to free preparations from a specific nucleic acid, to determine the structure of nucleic acids, and to study the mechanism of nucleic acid decomposition and synthesis.


Shapot, V. S. Nukleazy. Moscow, 1968.


References in periodicals archive ?
Uropathogenic specific protein gene, highly distributed in extraintestinal uropathogenic Escherichia coli, encodes a new member of H-N-H nuclease superfamily.
The disabling of the CCR5 gene by the nuclease, as well as the addition of the anti-HIV genes, created multiple layers of protection.
The main advantage of 5' nuclease pooled allelotyping is that it is a rapid, single-step procedure, requiring a minimum of reagents and no post-PCR processing.
The '674 Patent greatly strengthens the Company's ability to protect and capitalize on cells modified with DNE genome editing nucleases.
Inhibition of Ape1 Nuclease Activities by Lead, Iron, and Cadmium
In addition, pursuant to the agreement, Cellectis plant sciences receives a license under 2Blades TAL Code technology related to nucleases for commercial uses in certain specified crop plants.
The new technique employs zinc finger nuclease (ZFN) proteins, which can bind and cut DNA at precisely defined locations in the genome.
Topics of the ten papers include the biodistribution of metal ions, medicinal inorganic chemistry, the chemical toxicology of metals and metalloids, charge transport in biological molecules, bioorganometallic chemistry, interactions with metal ions, the bioorganic side of nucleic acid chemistry, nuclease and peptidase models, metalloporphyrins and metalloporphyrinoids, model complexes for enzymes containing vanadium, model complexes for enzymes containing molydbenum and tungsten, structural and functional models for oxygen-activated nonheme iron enzymes, model chemistry of iron-sulfur protein active sites and model complexes of enzymes containing nickel.
8,304,222 (the "'222 patent"), which relates to Precision BioSciences' Directed Nuclease Editor(TM) genome editing technology.
SAGEspeed Validated reagents include project-specific design and validation of nuclease activity.
The enzyme, which they named FAN1, appears to be a nuclease, which is capable of slicing through strands of DNA.