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A group of enzymes, widely distributed in nature, which catalyze hydrolysis of the internucleotide phosphodiester bonds in ribonucleic acid (RNA). The sites of hydrolysis may vary considerably, depending upon the specificity of the particular enzyme. Differences in specificity for the site of cleavage have led to the use of these various ribonucleases as tools in determining the structure and chemistry of RNA. See Enzyme, Nucleic acid

Research on ribonuclease has played a prime role in advancing the understanding of protein structure and function; also, it was the first protein to be totally synthesized from its component amino acids. Since the elucidation of the amino acid sequence of ribonuclease, much information has been compiled with regard to the three-dimensional structure of the enzyme and to specific regions of the molecule which are catalytically important. See Protein



an enzyme that depolymerizes ribonucleic acids and synthetic ribonucleotides by breaking the phosphodiester bonds of polynucleotide chains. Ribonucleases exhibit a high specificity in relation to the bases contained in nucleotides; the bonds between different nucleotides are hydrolyzed by different ribonucleases.

Pancreatic ribonuclease secreted by the pancreas of a bull was the first enzyme for which the primary structure, that is, the sequence of amino acids, was fully established (1960–62). The polypeptide chain of this enzyme consists of 124 amino-acid residues and contains four disulfide bridges that stabilize the enzyme’s spatial configuration. Pancreatic ribonuclease was first chemically synthesized in 1969.

In biochemical research ribonucleases are used in establishing the sequence of nucleotides in RNA, and in medicine they are used in treating certain viral diseases.


Khimiia biologicheski aktivnykh prirodnykh soedinenii. Moscow, 1970.
Nukleazy mikroorganizmov. Moscow, 1974.


C587H909N171O197S12 An enzyme that catalyzes the depolymerization of ribonucleic acid.
References in periodicals archive ?
Ilinskaya, "Bacillus intermedius ribonuclease (BINASE) induces apoptosis in human ovarian cancer cells," Toxicon, vol.
In the present work, we have studied the effect of bacterial ribonuclease binase on infectious titer of negative-sense single stranded RNA influenza A (H1N1pdm) virus after its single-cycle replication in A549 cell culture (12 h p.i.).
Characterization and use of the potent ribonuclease inhibitor aurintricarboxylic acid for the isolation of RNA from animal tissues.
The basal minimal medium (pH 5.5) used for ribonuclease production contained: glucose, 3%: beef extract, 0.5%: peptone, 1%: MgS[O.sub.4] x 7[H.sub.2]O, 0.05%: Ca[Cl.sub.2] x 2[H.sub.2]O, 0.01%.
A ubiquitin-like peptide with ribonuclease activity against various poly ho mo ribonucleotides from the yellow mushroom Cantharellus cibarius.
Degradation of DNA RNA hybrids by ribonuclease H and DNA polymerases of cellular and viral origin.
Gilliland, Protein Crystals Grown On Board MASER 3 Extend the Ribonuclease A Structure to 1.06 [Angstrom] Resolution, in Structure, Mechanism and Function of Ribonucleases, C.
However, transitions between glycine and aspartic acid at position 38 of ribonuclease are a regular feature within the class Mammalia - they occur also in rodents and kangaroos (Beintema et el.
Northern blot analysis with cesium-chloride-purified material further revealed that the RNA was not degraded by ribonuclease activity present during zooid regression.
The author and his colleagues have been working for over fifty years mainly on the structure and function of proteins and enzymes, especially certain groups of enzymes such as ribonucleases (RNases), peptidases and glutathione S-transferases.
Furthermore, miRNAs have been found to be stable to digestion by ribonucleases (RNAases), repeated freeze-thaw cycles, and prolonged storage (3).