Presentation on insilico drug design and virtual screening

In silico drug design and vitual screening

1. PRESENTATION ON INSILICO DRUG DESIGN AND VIRTUAL SCREENING TECHNIQUES PRESENTED BY- SUBHAM GHOSH M.PHARM,2 ND SEMESTER DIBRUGARH UNIVERSITY

2. Drug Design : Based on the knowledge of the biological target,finding a new medication is what we called as drug design. In Silico drug design: Drug design when performed in computers using computational softwares is known as in silico drug design. Since the electronic chips used in the computers are usually made up of silicon,hence came the name in silico drug design.

3. In silico is also an expression used to mean ‘performed on computer or via computer simulation.’ Types of In silico D rug Design : a.Ligand Based Drug Design b. Structure Based Drug Design

4. LIGAND BASED DRUG DESIGN Ligand : It is simply a molecule that binds to another. Often a soluble molecule such as hormone or neurotransmitter that binds to a receptor. In this type of drug design,the receptor is unknown but the ligand is known. It is also the statistical analysis of what groups are important for biological activity.

5. LBDD relies on the knowledge of other molecules that bind to the biological target of interest. Used to derive a pharmacophore . Also defines the minimum necessary structural characteristics a molecule must possess in order to bind to the target.

6. STRUCTURE BASED DRUG DESIGN In case of SBDD its just opposite of LBDD,where the receptor is known whereas the ligand is unknown. Completely relies on the knowledge of the 3D structure of the biological target. Methods by which the 3D structure of biological target are obtained are mentioned below.

7. X-ray crystallography NMR spectroscopy Homology modelling

8. VIRTUAL SCREENING TECHNIQUES Virtual screening is a computational technique used in drug discovery to search the libraries of small molecules in order to identify those structures which are most likely to bind to a drug target,typically a protein receptor or enzyme. It is also defined as a ‘automatically evaluating very large libraries of compounds’using computer programs.

9. CATEGORIES OF SCREENING There are two broad categories of screening techniques: A.Ligand based screening B.Structure based screening

10. Ligand -based: A model of the ligand can be built by exploiting the collective information contained in such set of ligands.These are known as pharmacophore models. A candidate ligand can there be compared to the pharmacophore model to determine whether it is compatible with it and therefore likely to bind. Another approach to LB virtual screening is to use 2D chemical similarity analysis method to scan a database of molecules against one or more active ligand structure.

11. A popular approach to LBVS is based on searching molecules with shape similar to that of known actives, as such molecules will fit the targets binding site and hence will be likely to bind the target. One of the important type of LBVS is- .Similarity based virtual screening:The similar property principle states that structurally similar molecules tends to have similar properties.

12. A active reference structure is provided and a database of compounds are ranked in an order based on similarity to the reference. Select the top ranking compound for biological testing. But similarity is inherently subjective,so need to provide a quantitative basis,a similarity measure,for ranking structures.

13. THANK YOU