Title: APPLICATIONS OF BIOINFORMATICS IN DRUG DISCOVERY AND PROCESS RESEARCH
1APPLICATIONS OF BIOINFORMATICS IN DRUG DISCOVERY
AND PROCESS RESEARCH
- Dr. Basavaraj K. Nanjwade M.Pharm., Ph.D
- Associate Professor
- Department of Pharmaceutics
- JN Medical College
- KLE University,
- Belgaum- 590010
2Bioinformatics
- Application of CS and informatics to biological
and Drug Development science - Bioinformatics is the field of science in which
biology, computer science, and information
technology merge to form a single discipline. - The ultimate goal of the field is to enable the
discovery of new biological insights as well as
to create a global perspective from which
unifying principles in biology can be discerned
3Bioinformatics Hub
4Bioinformatics Tools
- The processes of designing a new drug using
bioinformatics tools have open a new area of
research. However, computational techniques
assist one in searching drug target and in
designing drug in silco, but it takes long time
and money. In order to design a new drug one need
to follow the following path. - Identify target disease
- Study Interesting Compounds
- Detection the Molecular Bases for Disease
- Rational Drug Design Techniques
- Refinement of Compounds
- Quantitative Structure Activity Relationships
(QSAR) - Solubility of Molecule
- Drug Testing
5Bioinformatics Tools
- Identify Target Disease-
- 1. One needs to know all about the disease and
existing or traditional remedies. It is also
important to look at very similar afflictions and
their known treatments. - 2. Target identification alone is not sufficient
in order to achieve a successful treatment of a
disease. A real drug needs to be developed. -
6Bioinformatics Tools
- Identify Target Disease-
- 3. This drug must influence the target protein in
such a way that it does not interfere with normal
metabolism. - 4. Bioinformatics methods have been developed to
virtually screen the target for compounds that
bind and inhibit the protein.
7Bioinformatics Tools
- Study Interesting Compounds-
- One needs to identify and study the lead
- compounds that have some activity against a
disease. - 2. These may be only marginally useful and
- may have severe side effects.
- 3. These compounds provide a starting point
- for refinement of the chemical structures.
8Bioinformatics Tools
- Detect the Molecular Bases for Disease-
- If it is known that a drug must bind to a
particular spot on a particular protein or
nucleotide then a drug can be tailor made to bind
at that site. - This is often modeled computationally using any
of several different techniques. -
9Bioinformatics Tools
- Detect the Molecular Bases for Disease-
- 3. Traditionally, the primary way of
determining what compounds would be tested
computationally was provided by the researchers'
understanding of molecular interactions. - 4. A second method is the brute force testing
of large numbers of compounds from a database of
available structures.
10Bioinformatics Tools
- Rational drug design techniques-
-
- 1. These techniques attempt to reproduce the
researchers' understanding of how to choose
likely compounds built into a software package
that is capable of modeling a very large number
of compounds in an automated way. - 2. Many different algorithms have been used
for this type of testing, many of which were
adapted from artificial intelligence
applications. -
11Bioinformatics Tools
- Rational drug design techniques-
- 3. The complexity of biological systems makes it
very difficult to determine the structures of
large biomolecules. - 4. Ideally experimentally determined (x-ray or
NMR) structure is desired, but biomolecules are
very difficult to crystallize
12Bioinformatics Tools
- Refinement of compounds-
- 1. Once you got a number of lead compounds have
been found, computational and laboratory
techniques have been very successful in refining
the molecular structures to give a greater drug
activity and fewer side effects. -
13Bioinformatics Tools
- Refinement of compounds-
- 2. Done both in the laboratory and
computationally by examining the molecular
structures to determine which aspects are
responsible for both the drug activity and the
side effects.
14Bioinformatics Tools
- Quantitative Structure Activity Relationships
(QSAR)- - 1. Computational technique should be used to
detect the functional group in your compound in
order to refine your drug. - 2. QSAR consists of computing every possible
number that can describe a molecule then doing an
enormous curve fit to find out which aspects of
the molecule correlate well with the drug
activity or side effect severity. - 3. This information can then be used to suggest
new - chemical modifications for synthesis and
testing.
15Bioinformatics Tools
- Solubility of Molecule-
- 1. One need to check whether the target molecule
is water soluble or readily soluble in fatty
tissue will affect what part of the body it
becomes concentrated in. - 2. The ability to get a drug to the correct part
of the body is an important factor in its
potency. -
16Bioinformatics Tools
- Solubility of Molecule-
- 3. Ideally there is a continual exchange of
information between the researchers doing QSAR
studies, synthesis and testing. - 4. These techniques are frequently used and often
very successful since they do not rely on knowing
the biological basis of the disease which can be
very difficult to determine.
17Bioinformatics Tools
- Drug Testing-
- 1. Once a drug has been shown to be effective by
an initial assay technique, much more testing
must be done before it can be given to human
patients. - 2. Animal testing is the primary type of testing
at this stage. Eventually, the compounds, which
are deemed suitable at this stage, are sent on to
clinical trials. - 3. In the clinical trials, additional side
effects may be found and human dosages are
determined.
18Structure Prediction flow chart
19Computer-Aided Drug Design (CADD)
- Computer-Aided Drug Design (CADD) is a
specialized discipline that uses computational
methods to simulate drug-receptor interactions. - CADD methods are heavily dependent on
bioinformatics tools, applications and databases.
As such, there is considerable overlap in CADD
research and bioinformatics.
20Bioinformatics Supports CADD Research
- Virtual High-Throughput Screening (vHTS)-
- 1. Pharmaceutical companies are always searching
for new leads to develop into drug compounds. - 2. One search method is virtual high-throughput
screening. In vHTS, protein targets are screened
against databases of small-molecule compounds to
see which molecules bind strongly to the target. -
21Bioinformatics Supports CADD Research
- Virtual High-Throughput Screening (vHTS)-
- 3. If there is a hit with a particular
compound, it can be extracted from the database
for further testing. - 4. With todays computational resources, several
million compounds can be screened in a few days
on sufficiently large clustered computers. - 5. Pursuing a handful of promising leads for
further development can save researchers
considerable time and expense. - e.g.. ZINC is a good example of a vHTS
compound library.
22Bioinformatics Supports CADD Research
- Sequence Analysis-
- 1. In CADD research, one often knows the genetic
sequence of multiple organisms or the amino acid
sequence of proteins from several species. - 2. It is very useful to determine how similar or
dissimilar the organisms are based on gene or
protein sequences. -
23Bioinformatics Supports CADD Research
- Sequence Analysis-
- 3. With this information one can infer the
evolutionary relationships of the organisms,
search for similar sequences in bioinformatic
databases and find related species to those under
investigation. - 4. There are many bioinformatic sequence
analysis tools that can be used to determine the
level of sequence similarity.
24Bioinformatics Supports CADD Research
- Homology Modeling-
- Another common challenge in CADD research is
determining the 3-D structure of proteins. - 2. Most drug targets are proteins, so its
important to know their 3-D structure in detail.
Its estimated that the human body has 500,000 to
1 million proteins. - 3. However, the 3-D structure is known for only
a small fraction of these. Homology modeling is
one method used to predict 3-D structure.
25Bioinformatics Supports CADD Research
- Homology Modeling-
- 4. In homology modeling, the amino acid sequence
of a specific protein (target) is known, and the
3-D structures of proteins related to the target
(templates) are known. - 5. Bioinformatics software tools are then used to
predict the 3-D structure of the target based on
the known 3-D structures of the templates. - 6. MODELLER is a well-known tool in homology
modeling, and the SWISS-MODEL Repository is a
database of protein structures created with
homology modeling.
26Bioinformatics Supports CADD Research
- Similarity Searches-
- 1. A common activity in biopharmaceutical
companies is the search for drug analogues. - 2. Starting with a promising drug molecule, one
can search for chemical compounds with similar
structure or properties to a known compound. - 3. There are a variety of methods used in these
searches, including sequence similarity, 2D and
3D shape similarity, substructure similarity,
electrostatic similarity and others. - 4. A variety of bioinformatic tools and search
engines are available for this work
27Bioinformatics Supports CADD Research
- Drug Lead Optimization-
-
- 1. When a promising lead candidate has been found
in a drug discovery program, the next step (a
very long and expensive step!) is to optimize the
structure and properties of the potential drug. - 2. This usually involves a series of
modifications to the primary structure (scaffold)
and secondary structure (moieties) of the
compound. -
28Bioinformatics Supports CADD Research
- Drug Lead Optimization-
- 3. This process can be enhanced using software
tools that explore related compounds
(bioisosteres) to the lead candidate. OpenEyes
WABE is one such tool. - 4. Lead optimization tools such as WABE offer a
rational approach to drug design that can reduce
the time and expense of searching for related
compounds.
29Bioinformatics Supports CADD Research
- Physicochemical Modeling-
- 1. Drug-receptor interactions occur on atomic
scales. - 2. To form a deep understanding of how and why
drug - compounds bind to protein targets, we must
consider - the biochemical and biophysical properties
of both the - drug itself and its target at an atomic
level. - 3. Swiss-PDB is an excellent tool for doing
this. Swiss-PDB - can predict key physicochemical properties,
such as - hydrophobicity and polarity that have a
profound - influence on how drugs bind to proteins.
30Bioinformatics Supports CADD Research
- Drug Bioavailability and Bioactivity-
- 1. Most drug candidates fail in Phase III
clinical trials after many years of research and
millions of dollars have been spent on them. And
most fail because of toxicity or problems with
metabolism. - 2. The key characteristics for drugs are
Absorption, Distribution, Metabolism, Excretion,
Toxicity (ADMET) and efficacyin other words
bioavailability and bioactivity. - 3. Although these properties are usually measured
in the lab, they can also be predicted in advance
with bioinformatics software.
31Benefits of CADD
- Cost Savings-
- 1. The Tufts Report suggests that the cost of
drug discovery and development has reached 800
million for each drug successfully brought to
market. - 2. Many biopharmaceutical companies now use
computational methods and bioinformatics tools to
reduce this cost burden. -
32Benefits of CADD
- Cost Savings-
- 3. Virtual screening, lead optimization and
predictions of bioavailability and bioactivity
can help guide experimental research. - 4. Only the most promising experimental lines of
inquiry can be followed and experimental
dead-ends can be avoided early based on the
results of CADD simulations.
33Benefits of CADD
-
- Time-to-Market-
- 1. The predictive power of CADD can help drug
research programs choose only the most promising
drug candidates. - 2. By focusing drug research on specific lead
candidates and avoiding potential dead-end
compounds, biopharmaceutical companies can get
drugs to market more quickly.
34Benefits of CADD
- Insight-
- 1. One of the non-quantifiable benefits of CADD
and the use of bioinformatics tools is the deep
insight that researchers acquire about
drug-receptor interactions. - 2. Molecular models of drug compounds can reveal
intricate, atomic scale binding properties that
are difficult to envision in any other way. -
35Benefits of CADD
- Insight-
- 1. When we show researchers new molecular models
of their putative drug compounds, their protein
targets and how the two bind together, they often
come up with new ideas on how to modify the drug
compounds for improved fit. - 2. This is an intangible benefit that can help
design research programs.
36CADD
- CADD and bioinformatics together are a powerful
combination in drug research and development. - An important challenge for us going forward is
finding skilled, experienced people to manage all
the bioinformatics tools available to us, which
will be a topic for a future article.
37Research Achievements
- Software developed
- Bioinformatics data base developed
- Traditional medicine research tools developed
38Software developed
- 1. SVMProt Protein function prediction software
- http//jing.cz3.nus.edu.sg/cgi-bin/svmprot.cgi
- 2. INVDOCK Drug target prediction software
- 3. MoViES Molecular vibrations evaluation server
- http//ang.cz3.nus.edu.sg/cgi-bin/prog/norm.pl
39Bioinformatics database developed
- 1. Therapeutic target database
- http//xin.cz3.nus.edu.sg/group/cjttd/ttd.asp
- 2. Drug adverse reaction target database
- http//xin.cz3.nus.edu.sg/group/drt/dart.asp
- 3. Drug ADME associated protein database
- http//xin.cz3.nus.edu.sg/group/admeap/admeap.
asp - 4. Kinetic data of biomolecular interactions
database - http//xin.cz3.nus.edu.sg/group/kdbi.asp
- 5. Computed ligand binding energy database
- http//xin.cz3.nus.edu.sg/group/CLiBE/CLiBE.asp
40Traditional medicine research tools developed
- 1. Traditional medicine information database
- 2. Herbal ingredient and content database
- 3. Natural product effect and consumption
- info system
- 4. Traditional medicine recipe prediction and
- validation system
- 5. Herbal target identification system
41- E-mail bknanjwade_at_yahoo.co.in