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A ribonucleic acid (RNA) molecule that, like a protein, can catalyze specific biochemical reactions. Examples include self-splicing rRNA and RNase P, both involved in catalyzing RNA processing reactions (that is, the biochemical reactions that convert a newly synthesized RNA molecule to its mature form). Different ribozyme structures catalyze quite distinct RNA processing reactions, just as protein enzyme families that are composed of different structures catalyze different types of biochemical reactions.

Ribozymes share many similarities with protein enzymes, as assessed by two parameters that are used to describe a biological catalyst. The Michaelis-Menten constant Km relates to the affinity that the catalyst has for its substrate, and ribozymes possess Km values which are comparable to Km values of protein enzymes. The catalytic rate constant describes how efficiently a catalyst converts substrate into product. The values of this constant for ribozymes are markedly lower than those values observed for protein enzymes. Nevertheless, ribozymes accelerate the rate of chemical reaction with specific substrates by 1011 compared with the rate observed for the corresponding uncatalyzed, spontaneous reaction. Therefore, ribozymes and protein enzymes are capable of lowering to similar extents the activation energy for chemical reaction. See Enzyme, Protein, Ribonucleic acid (RNA)


A ribonucleic acid molecule that can catalyze, or lower the activation energy for, specific biochemical reactions.
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The new enzyme is called a ribozyme because it is made from ribonucleic acid (RNA).
Previous research by Liu and Lu showed that Salmonella could effectively sneak the anti-viral ribozymes into human cells infected with human cytomegalovirus and reduce the viral load of the cell cultures.
The Vif5113 and Vif5113A ribozymes were synthesized (5'ACA TAT GGT GTT TCT GAT GAG TCC GTG AGG ACG A/GAA CTA ATC TTT TCC AT 3') and cloned into the shuttle vector pPCR-Script (Stratagene) as previously described (18).
A biochemist, Breaker has worked on synthetic ribozymes for many years.
Hammerhead ribozymes are made up of 3 base-paired helices composed of approximately 30 nucleotides each that form a wishbone or "Y" configuration (2).
We continue to focus on our goals of optimizing the value of our ribozyme technology platform to include a diagnostic and nucleic acid technology strategy.
Ribozyme continues to maintain a dominant intellectual property position in the field of ribozymes providing a solid foundation for future research and development.
He has created a molecule that mimics the behavior of a kind of naturally occurring RNA called a ribozyme, which acts as a catalyst.
Ribozymes, however, can be designed to cut up the very genetic material that HIV would need to reproduce itself.
The research team looked at a lab-grown ribozyme that catalyzes the Diels-Alder reaction, which has broad applications in organic chemistry.
Cleavage of tat mRNA sequences by hammerhead ribozymes may negatively impact transcription initiation and elongation, leading to the inability of HIV to replicate within cells (10;11).
Ribozymes are RNA molecules that catalyze sequence specific cleavage of RNA substrates in a sequence specific manner.