Transcript Drug discovery

Biotechnology
in Medicine
Chapter 12
Learning Outcomes
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Discuss the scope and role of medical biotechnology in the
healthcare industry
Explain the function of drugs and discuss how they may be
created using combinatorial chemicals
Describe the various high-throughput screening processes for
potential drug activity
Explain the methods for synthesizing peptides and
oligonucleotides and discuss the uses of each
Detail the multiple uses of antibodies in medical biotechnology
and discuss the immune response that results from vaccinations
12.1 Drug Discovery
Medical biotechnology includes R&D in the following areas:
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Causes of diseases and disorders
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Drugs, pharmaceuticals, and medicines derived from nature
or through genetic engineering and/or combinatorial
chemistry
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Disease prevention, vaccines, and gene therapy
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Diagnostics for medical applications
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Prosthetics or instruments for replacement or improvement of
tissues and organs
Drug Development
Drugs are chemicals that alter the effects of proteins or other molecules
associated with a disease-causing mechanism
A drug is usually specific for a particular disease process
Sources of Potential Drugs
The drug discovery process may involve finding chemical compounds that
show activity against one or more molecules associated with a disease.
The process is lengthy and often tedious.
Vocabulary
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Medicine – something that prevents or treats disease or alleviates the symptoms of disease
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Medical biotechnology – all the areas of research, development, and manufacturing of
items that prevent or treat disease or alleviate the symptoms of disease
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Drug – chemical that alters the effects of proteins or other molecules associated with a
disease-causing mechanism
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Drug discovery – the process of identifying molecules to treat a disease
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Organic synthesis – the synthesis of drug molecules in a laboratory from simpler, preexisting molecules
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Screening – the assessment of hundreds, thousands, or even millions of molecules or
samples
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Pathogenesis – the origin and development of a disease
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Combinatorial chemistry – the synthesis of larger organic molecules from smaller ones
12.1 Review Questions
1.
What kinds of organisms cause diseases?
2.
Where are drugs typically discovered?
3.
How is aspirin an example of combinatorial chemistry?
12.2 Creating Pharmaceuticals through Combinatorial Chemistry
Natural compounds must sometimes be modified to be more useful or effective.
Techniques for Creating New Drugs
Combinatorial chemistry is the process of creating new and varied organic
compounds by linking chemical building blocks.
Screening Compounds
Some drug screening must take place in animal or human cells.
Most can be screened on sophisticated instruments.
Vocabulary
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Parallel synthesis – making large numbers of batches of similar compounds at the same
time
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Library – a collection of compounds, such as DNA molecules, RNA molecules, and proteins
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Biochip – a special type of microarray that holds thousands of samples on a chip the size of
a postage stamp
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Microarray – a small glass slide or silicon chip with thousands of samples on it that can be
used to assess the presence of a DNA sequence related to the expression of certain proteins
12.2 Review Questions
1.
What is the value of combinatorial chemistry?
2.
How are chemical compound libraries related to high-throughput
screening?
3.
What is the value of microarray technology?
12.3 Creating Pharmaceuticals through
Peptide and DNA Synthesis
A peptide can be used in an attempt to identify regulator molecules.
A peptide may be used as a vaccine antigen to initiate an antibody
response.
Peptides are often synthesized for use in the purification of other proteins.
Oligonucleotide Synthesis
Scientists have learned to make small pieces of DNA, called
oligonucleotides.
Vocabulary
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Peptides – short amino acid chains that are not folded into a functional protein
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Peptide synthesizer – an instrument that is used to make peptides, up to a maximum of a
few dozen amino acids in length
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Oligonucleotides – segments of nucleic acid that are 50 nucleotides or less in length
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DNA synthesizer – an instrument that produces short sections of DNA, up to a few
hundred base pairs in length
12.3 Review Questions
1.
What are three uses of peptides in medicinal biotechnology?
2.
How does a peptide synthesizer make peptides?
3.
How does a DNA synthesizer make oligonucleotides?
4.
Of what value are oligonucleotides?
12.4 Creating Pharmaceuticals by
Protein/Antibody Engineering
Large proteins can be synthesized through genetic engineering.
Antibodies are the most complicated of all proteins.
Using Antibodies to Purify Proteins
Antibodies are often needed in large quantities.
Using Antibodies to
Recognize Molecules
Antibodies may be used to recognize molecules in medical research
applications.
Using Antibodies and
Antigens in Vaccines
Antibody-antigen reactions are important in disease
prevention.
Vocabulary
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Slow cytometry – a process by which cells are sorted by an instrument, a cytometer,
that recognizes fluorescent antibodies attached to surface proteins on certain cells
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Vaccine – an agent that stimulates the immune system to provide protection against a
particular antigen or disease
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B-cells – specialized cells of the immune system that are used to generate and release
antibodies
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Memory cell – a specialized type of B-cell that remains in the body for long periods of
time with the ability to make antibodies to a specific antigen
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Immunity – protection against any foreign disease-causing agent
12.4 Review Questions
1.
How are antibodies used in flow cytometry?
2.
How does a vaccine increase the number of antibodies in a person?
3.
How does a vaccine provide immunity?
Questions and Comments?