Artificial enzymes may be defined as the synthetic, organic molecule prepare to recreate/mimic the active site of an natural enzyme.

1. ARTIFICIAL ENZYMES
Under the guidance of:
•Dr. M. Murali Krishna
•Dept of Pharmaceutical Chemistry
AU COLLEGEOF PHARMACEUTICAL SCIENCES, VISAKHAPATNAM
• Presented By:
• Gandham Malasree
• Regd no: 620209502002
• Dept of Pharmaceutical Chemistry

2. enzyme
• Enzymes are biological catalysts.
• A Catalyst is defined as "a substance that increases the rate of a chemical reaction
without being itself changed in the process.”
Enzymes as Biological Catalysts:
• Enzymes are proteins that increase the rate of reaction by lowering the energy of
activation.
• They catalyze nearly all the chemical reactions taking place in the cells of the body .
• Enzymes have unique three-dimensional shapes that fit the shapes of reactants
(substrates ).

3. PROPERTIESOFENZYMES
• Catalytic efficiency – high efficiency, 103 to 1017 faster than the
corresponding catalyzed reactions.
• Specificity - high specific specificity, interacting with one or a few
specific substrates and catalyzing only one type of chemical reaction.
• Mild reaction conditions- 37℃, physiological pH, ambient
atmospheric pressure.

4. Artificial enzymes
 Artificial enzymes may be defined as the synthetic, organic molecule prepare to
recreate/mimic the active site of an natural enzyme.
 The binding of a substrate close to functional groups in the enzyme causes catalysis
by so called proximity effects.
 It is therefore possible to create similar catalysts from small molecule which will
mimics the enzyme active sites.
 Since the artificial enzymes need to bind molecules, they are made based on the host
molecule such as cyclodextrins, crown ethers or calixarene etc.
 They have a molecular weight less than 2000 Dalton.
 They have the ability to stabilize at high temperature.
 They are also known as synzymes or enzyme mimics.

5. EXAMPLES:
 XNAzymes are capable of cutting and joining strands of RNA in a test tube. These are used in
the treatment of various diseases like cancer and viral infections. These are not recognized by
bodys natural degrading enzymes as they are extremely robust.
 Manganese dioxide(Mn3O4) ROS (reactive oxygen species ) scavenging activities have been
developed for in vivi anti – inflammation.
 Vanadium pentoxide mimics to glutathione peroxide.

6. IDEALCHARACTERISTICS OF ARTIFICIALENZYMES
Hydrogen bonding and/or electrostatic binding sites
complementary to the substrate.
Catalytic group attached to the model.
Rigid structure model.
Water soluble and catalytically active under physiological
conditions.
Reversable, non-covalent binding with the release slower
than the binding.

7. Need of artificial enzymes:
• Tunable structures and catalytic efficiencies similar to natural
enzymes.
• Excellent tolerance to experimental conditions.
• Purely synthetic routes for their preparation.
• High cast and low stability limit the applications of natural enzymes.
• Speeds up the reaction at a relatively high rate.

8. DESIGNAPPROACH FOR ARTIFICIAL ENZYME
Two types of approaches used to develop artificial enzymes.
1.Chemical approach:
• Cyclodextrins as enzyme mimics
• Cyclophane as enzyme mimics
• Calixarene as enzyme mimics
• Crown ethers as enzyme mimics
2.Biological approach:
• Direct evolution method for artificial enzyme production
• De novo computational enzyme designing

9. Cyclodextrins:
The three most common cyclodextrins are , α-
,β-,and γ-species, which are composed of six,
seven, and eight glucopyranose units,
respectively.
Hydrophobic cavity.
Stable and water soluble.
Tunable (modify to change properties)
Research on cyclodextrin started in1930s
very expensive &thought to be toxic
1970s – non toxic.

10. DIRECT EVOLUTIONMETHOD FOR ARTIFICIAL ENZYME PRODUCTION
oDirect evolution is a molecular biology method to modify biocatalysts via in
vitro version of “Darwinian evolution”.
oDirect evolution provide improved enzymatic activity, thermostability,
tolerance to organic solvent, substrate specificity, enantioselectivity and so on.
Gene mutagenesis
Insertion into host
Transformed colony
Eg: Sitagliptin

11. Insertion of gene
sequence into host cell
Transformed colony
plating
Bacteria producing
mutant ezymes
Screening for
transformed colonies
Evaluate by using
enzymatic assays
Gene mutagenesis
More production of
transformed colonies
Eg: SITAGLIPTIN – it is used to treat patients with type 2 diabetes and high blood pressure

12. De Novo Computational Enzyme Designing
 Under this automated identification of amino acid sequences performed that will fold into a
specified three-dimensional structures. This method has emerged as a promising tool for
engineering enzymes .
 Conformational changes are part of the repertoire that natural enzymes use to catalyze reactions.
 In order to select candidates sequences for enzymes at each step of the identified pathways,
several tools provide different solutions, including anti SMASH for biosynthetic gene clusters.
Tools used:
• Path pred
• RDM patterns
• Bond-Electron matrices
• Reactions SMARTS in Retro
• Path 2.0

13. Ideal Environment Requirement For Artificial Enzymes
 The covalent immobilization of one enzyme on solid supports having large surfaces with
given properties (eg., hydrophilic or hydrophobic surfaces) should provide a nano
environment surrounding the area of the enzyme directly in contact with the support.
 Further covalent immobilization of macromolecular polymers (hydrophilic, hydrophobic) on
the same large internal surfaces of the solid support should provide an additional nano
environment surrounding the area of the immobilized enzyme molecules next to the support.
 Chemical modification of immobilized enzymes with polyfunctional macromolecules could
also be an interesting way to greatly modified the enzyme nano environment with minimal
chemical modification of the enzyme.

14. APPLICATIONS
• Tunable structure and catalytic efficiencies similar to natural enzymes.
• Excellent tolerance to experimental conditions.
• Purely synthetic routes for their preparation.
• Lower cost.
Pharmaceutical : synthetic enzymes that accelerates the formation of drugs and
chemicals.
Medicine : use of synthetic enzymes as supplements for patients deficient in certain
enzyme can be made instead of extracting natural enzymes from other organisms.
Genetic Engineering : potentially designing synthetic enzymes that manipulate gene
sequences to create genetically modified organisms or to help genealogy research.