2. Ribozyme
• • Ribozyme' or 'RNAzyme' are catalytic RNA capable of catalyzing
biochemical reactions like enzymes.
• • Discovery of ribozymes revealed that RNA contributed to the
'RNA world hypothesis - first living forms originated from RNA
• • Their major role in biological systems includes:
• Hydrolysis of phosphodiester bonds
• Formation of bonds.
• Catalyze amino transferase activity of the ribosome
• eg: RNA Polymerase
• Amino acyl Transferase
• RNAse P
3. • Ribozymes are RNA molecules that fold into complex three-dimensional structures.
• The specific structure of a ribozyme is crucial for its function as an enzyme.
• Ribozymes typically consist of a catalytic core region surrounded by other structural elements.
• The catalytic core of a ribozyme often contains specific nucleotides that are involved in
catalyzing a chemical reaction.
• The structural elements surrounding the catalytic core can help to stabilize the ribozyme's
overall structure and provide binding sites for other molecules.
• Some ribozymes have additional structural features, such as "arms" or "loops," that help to
position the catalytic core and facilitate interactions with other molecules.
• The structure of a ribozyme can be determined using techniques such as X-ray crystallography
or nuclear magnetic resonance (NMR) spectroscopy.
• Understanding the structure of ribozymes is important for developing drugs that can target
specific ribozymes or for engineering ribozymes with new catalytic activities.
4. Characteristics of Ribozyme
• Contrary to central dogma and very rare in biological systems.
• Ribozymes are present in the organelles of eukaryotes
•
• (nucleus, mitochondria and chloroplasts), amphibians, prokaryotes, bacteriophages,
viroids and in satellite viruses that infect plants
• Metal ions like K+, Mg2+ are required for catalyzing reaction
• Possess self catalytic property especially in NUX pattern of nucleotides (N represents
any nucleotide, U represents uracil, and X can be adenine, uracil, or cytosine).
• Molecular scissors or staplers, having role in splicing, RNA ligation, oligo nucleotide
chain extension, endonuclease action, phosphatase action
5. Structure of Ribozyme
• Ribozymes are RNA molecules that fold into complex three-
dimensional structures.
• The specific structure of a ribozyme is crucial for its function as an
enzyme.
• Ribozymes typically consist of a catalytic core region surrounded by
other structural elements.
• The catalytic core of a ribozyme often contains specific nucleotides
that are involved in catalyzing a chemical reaction.
6. • The structural elements surrounding the catalytic core can help to stabilize the
ribozyme's overall structure and provide binding sites for other molecules.
• Some ribozymes have additional structural features, such as "arms" or "loops,"
that help to position the catalytic core and facilitate interactions with other
molecules.
• The structure of a ribozyme can be determined using techniques such as X-ray
crystallography or nuclear magnetic resonance (NMR) spectroscopy.
• Understanding the structure of ribozymes is important for developing drugs that
can target specific ribozymes or for engineering ribozymes with new catalytic
activities
7.
8. Mechanism of Ribozyme
• Ribozymes are RNA molecules that catalyze chemical
reactions, much like protein enzymes.
• The catalytic mechanism of a ribozyme involves binding to a
substrate molecule and facilitating a chemical reaction.
• The catalytic core of a ribozyme contains specific nucleotides
that are involved in catalyzing the reaction.
• The ribozyme brings the reactive groups in the substrate into
close proximity and provides an environment
9.
10. • In some cases, the ribozyme may also directly participate in the
chemical reaction, using specific nucleotides to act as a
catalyst.
• Once the reaction is complete, the product is released from
the ribozyme, allowing the ribozyme to bind to another
substrate molecule and repeat the process.
• The mechanism of ribozymes can vary depending on their
structure and the specific reaction they catalyze.
• Understanding the mechanism of ribozymes is important for
designing new ribozymes with novel catalytic activities and for
developing drugs that can target specific ribozymes
13. • Hammerhead ribozyme:
This ribozyme is found in
certain plant viruses and
is able to cleave RNA at
specific sites. It has a
characteristic
"hammerhead"
structure, with three
stem-loops that form a
central catalytic core.
14. • Hairpin ribozyme:
This ribozyme is
found in certain plant
viroids and is able to
cleave RNA at specific
sites. It has a hairpin-
like structure, with a
central loop that
forms the catalytic
core.
15. • Ribonuclease P: This ribozyme is found in all living
organisms and is involved in processing transfer
RNA (tRNA) molecules. It has a complex structure,
with a catalytic core composed of both RNA and
protein components.
16. • Group I intron: This ribozyme is found in
certain organisms, including bacteria and
yeast, and is involved in the splicing of RNA. It
has a complex structure, with a central
catalytic core that is surrounded by several
structural domains.
17. • Group II intron: This
ribozyme is found in
certain bacteria and
is involved in the
splicing of RNA. It
has a complex
structure, with a
catalytic core that is
composed of both
RNA and protein
components.
18. Artificial Ribozyme
• Artificial ribozymes are RNA molecules that are designed and synthesized in the
laboratory to perform specific catalytic functions.
• They can be created by modifying existing ribozymes or by designing new RNA
sequences that can fold into specific structures with catalytic activity.
• Artificial ribozymes have numerous applications in biotechnology, medicine, and
nanotechnology, including gene therapy, biosensors, biocatalysis, and molecular
computing.
• They can be designed to cleave and destroy specific RNA molecules, recognize
specific molecules or ions, catalyze specific chemical reactions, and perform
logical operations based on their catalytic activity.
19. • Artificial ribozymes are an important tool for studying the
mechanism of ribozyme catalysis and for developing new RNA-
based technologies.
• The design and optimization of artificial ribozymes require a deep
understanding of RNA structure, folding, and catalysis, as well as
the principles of chemical kinetics and thermodynamics.
• In recent years, advances in computational modeling and high-
throughput sequencing have enabled the rapid and efficient
design of artificial ribozymes with novel and useful catalytic
functions.
