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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, "Antiviral activity of bacterial extracellular ribonuclease against single-, double-stranded RNA and DNA containing viruses in cell cultures," BioNanoScience, vol.
Demonstration of ribonuclease activity in the plant ribosome-inactivating proteins alpha- and beta-momorcharins.
Isolation of a novel thermolabile heterodimeric ribonuclease with antifungal and antiproliferative activities from roots of the sanchi ginseng Panax notoginseng.
Based on these results, Ribonuclease A is more hydrophobic than Cytochrome C and hence shows better retention on Nuvia cPrime Resin (Bio-Rad), which is a multi-modal resin that allows both cation exchange and hydrophobic interactions.
D'Alessio, "The cytosolic ribonuclease inhibitor contributes to intracellular redox homeostasis," FEBS Letters, vol.
Barreto, "Direct inhibition of oncogenic KRAS by Bacillus pumilus ribonuclease (binase)," Biochimica et Biophysica Acta (BBA)--Molecular Cell Research, vol.
Ilinskaya, "Bacillus intermedius ribonuclease (BINASE) induces apoptosis in human ovarian cancer cells," Toxicon, vol.
The HIV-1 RT is a multifunctional protein endowed of two main enzymatic functions: an RNA-Dependent DNA Polymerase (RDDP) activity, which accounts for the formation of the RNA: DNA intermediate, and a Ribonuclease H (RNase H) activity, involved in the hydrolytic cleavage of the RNA strand of the RNA: DNA hybrid (Esposito et al., 2012b).
According to the researchers, OAS1 catalyses the synthesis of 2?-5?-linked oligomers of adenosine from adenosine triphosphate (2-5A), which then binds and activates Ribonuclease L (RNase L).
Gibberellic acid-enhanced synthesis and release of alpha-amylase and ribonuclease by isolated barley and aleurone layers.
The [sup.3]H-labeled 3'-terminal nucleoside was cleaved by ribonuclease and was analyzed by two dimensional paper chromatography that can identify nucleoside derivatives (A', C', G' and U') with modified ribose residues.