Computational mutagenesis studies of hammerhead ribozyme catalysis
1BioMaPS Institute for Quantitative Biology and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, USA.
Journal of the American Chemical Society
|September 4, 2010
Summary
Computational simulations reveal key interactions in the hammerhead ribozyme (HHR). Understanding these molecular dynamics helps explain mutation effects and guides future research on this important catalytic RNA.
Area of Science:
- Biochemistry
- Molecular Biology
- Computational Chemistry
Background:
- The hammerhead ribozyme (HHR) is a small catalytic RNA molecule.
- Understanding the structural basis of HHR's catalytic activity is crucial for its study.
Purpose of the Study:
- To computationally investigate the effects of mutations at specific positions (C3, G8, G5) in the HHR.
- To explain experimentally observed mutational effects using molecular dynamics simulations.
Main Methods:
- Performed twenty-four 100-ns molecular dynamics simulations of native and mutated HHR.
- Simulated both reactant and activated precursor states, including a deprotonated G8:2'OH.
- Analyzed Watson-Crick base-pairing, hydrogen bond networks, and base stacking interactions.
Main Results:
- Identified Watson-Crick base-pairing (G8-C3), hydrogen bonds (C17-G5), and base stacking (G8-C1.1) as critical for HHR active site structure and activity.
- Disruption of these interactions negatively impacts catalytic activity.
- Predicted a rescue effect for the C3U/G8D double mutant.
Conclusions:
- Mutation simulations require adequate relaxation time (≥30 ns) for effects to manifest.
- Examining states beyond the reactant state is necessary for interpreting mutational effects in catalytically active structures.
- These findings enhance understanding of experimental mutational effects and highlight conserved features essential for HHR active site integrity.
Related Concept Videos
01:16In vitro Mutagenesis
To learn more about the function of a gene, researchers can observe what happens when the gene is inactivated or “knocked out,” by creating genetically engineered knockout animals. Knockout mice have been particularly useful as models for human diseases such as cancer, Parkinson’s disease, and diabetes.
02:47Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
02:47Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
01:16In-vitro Mutagenesis
To learn more about the function of a gene, researchers can observe what happens when the gene is inactivated or “knocked out,” by creating genetically engineered knockout animals. Knockout mice have been particularly useful as models for human diseases such as cancer, Parkinson’s disease, and diabetes.
01:13Introduction to Mechanisms of Enzyme Catalysis
For many years, scientists thought that enzyme-substrate binding took place in a simple "lock-and-key" fashion. This model stated that the enzyme and substrate fit together perfectly in one instantaneous step. However, current research supports a more refined view scientists call induced fit. The induced-fit model expands upon the lock-and-key model by describing a more dynamic interaction between enzyme and substrate. As the enzyme and substrate come together, their interaction causes a mild...
01:13Introduction to Mechanisms of Enzyme Catalysis
For many years, scientists thought that enzyme-substrate binding took place in a simple "lock-and-key" fashion. This model stated that the enzyme and substrate fit together perfectly in one instantaneous step. However, current research supports a more refined view scientists call induced fit. The induced-fit model expands upon the lock-and-key model by describing a more dynamic interaction between enzyme and substrate. As the enzyme and substrate come together, their interaction causes a mild...