Pharmaceutical Biotechnology Flashcards
What is pharmaceutical biotechnology?
A field that uses micro- and macro-organisms and genetically engineered cells to create pharmaceuticals
What are primarily application of techniques of biotechnology?
discovery research
product development
List difference applications of biotechnology in pharmacy
Antibiotic production
Antibody production
Transgenic animals
Gene therapy and Gene silencing
Vaccines
Personalized medicine
What is the pharmacists role in biotechnology?
product evaluation and selection
pt education and counselling
provision of drug information
assistance in patient monitoring
drug control and preparation
Go through the central dogma
DNA - transcription –> RNA — translation–> protein
What are housekeeping genes?
they are responsible for the routine metabolic functions common to all cells
What is recombinant DNA?
form of artificial DNA that is created by combining two sequences from different sources
What is recombinant DNA technology?
tech which allows proteins to be produced via artificial means
engineer gene for more protein productivity
produce desired protein in vitro for therapeutic use
What is the most used recombinant cells used to mass produce proteins?
E. coli
List advantages of engineering prokaryotes
cultivation of prokaryotes is easy
gene manipulation is easy as plasmid DNA is easy to isolate and manipulate
List the steps in DNA cloning
- Isolation of gene of interest
- Isolation of plasmid DNA (Cloning vector)
- Manipulation of DNA sequence
a. Cutting- Restriction enzymes
b. Joining- DNA ligase - Transformation of bacteria
- Selection of “correct” bacteria
- Replication of the cells carrying rDNA molecules to get a genetically identical cells or clone.
What are the three essential features for cloning vector?
1) Origin of replication
2) Dominant selectable marker
3) Restriction sites
What is extrachromosomal self-replicating DNA molecules?
plasmids
Define restriction endonucleases
primarily bacterial enzymes that cut foreign DNA into fragments by recognizing specific nucleotide base pairs.
Define DNA ligase
have the unique ability to link or “paste” together DNA fragments that have been produced by exposure to restriction endonucleases.
List methods of transformation
Heat shock
CaCl2 Transformation
Lipofectin® and similar molecules
Electroporation
Microinjection
To make the recombinant plasmid permeable to DNA molecules, which of the chemicals is added?
a) MgCl2
b) CaCl2
c) NaCl
d) HCl
B) CaCl2
Generally a plasmid vector contains how many elements?a) 1b) 2c) 3d) 4
C) 3
Which of the following enzyme is required for end to end joining of DNA?a) DNA ligaseb) Restriction endonucleasec) RNA polymerased) DNA polymerase
A) DNA ligase
Which of the following enzyme is responsible for making a DNA copy from RNA?a) Reverse transcriptaseb) DNA polymerasec) RNA polId) RNA polII
A) reverse transcriptase
Can two DNAs cut with different restriction enzymes join together to form a recombinant plasmid?
Yes, if they are cut at the same place they will match
Compare small molecule drugs and biological drugs
Based on Size
small
low molecular weight
large
high molecular weight
Compare small molecule drugs and biological drugs
Based on structure
simple, well defined, independent of manufacturing process
complex defined by the exact manufacturing process
Compare small molecule drugs and biological drugs
Based on modification
well defined
many options
Compare small molecule drugs and biological drugs
Based on manufacturing
produced by chemical synthesis
predictable chemical process
identical copy can be made
produced in living cell culture
difficult to control from starting material to final API
impossible to ensure identical copy
Compare small molecule drugs and biological drugs
Based on characteristics
easy to characterise completely
cannot be characterised completely the molecular composition and heterogeneity
Compare small molecule drugs and biological drugs
Based on stability
stable
unstable, sensitive to external conditions
Compare small molecule drugs and biological drugs
Based on immunogenicity
mostly non-immunogenic
immunogenic
What was the first example of biotech products?
insulin
List the phase of growth curve of bacteria
LAG Phase:
Number of bacteria does not change with time in lag phase.
LOG Phase:
Number of bacteria increases exponentially in log phase.
STATIONARY Phase:
There is no net change in number of bacteria with time in stationary phase. Bacteria divide but also die at same rate.
DEATH Phase:
Number of bacteria decreases with time
What is Rifamycin B?
a substance produced by bacteria
it both inhibit transcription by binding prokaryotic but not eukaryotic RNA polymerases
What does the structural model of rifampicin indicate?
that rifampicin sterically blocks the path of RNA elongation when the transcript becomes two or three nucleotides long
Why can’t bacteria always be used to make all drugs?
bacteria do not show some post translational modifcation
What is different about the expression system in bacteria?
they are not capable of producing glycoproteins because they lack the capacity to glycoylate
List some post tranlational modifications
phosporylation
glycosylation
ubiquitination
nitrosylation
methylation
acetylation
lipidation
list some areas where cell culture technology is currently playing a major role
model systems for basic cell biology
toxicity testing
cancer research
making drugs
What are the 2 classes of cultures of animal cells?
primary cells
cell lines
What is primary culture?
when cells are surgically removed from an organism and placed in a culture to grow, divide and live
most have a finite lifespan
Explain Hayflick’s Phenomenon
cell will continue to grow and divide normally for a limited number of passages
the number of passages decrease when cells are harvested from older individuals
What is a cell line?
if the cells in a cell strain undergo a process that makes them “immortal”
What are some processes used to make cells immortal?
chemical or gamma
viral infections with antigen
Define suspension cell culture
derived from cells which can divide and
survive without being attached to a substrate,
e.g. cells of haemopoietic lineage.
* Can be maintained in culture vessels that are
not tissue-culture treated.
* Requires agitation for adequate gas exchange.
* Easier to passage
Explain Adherent cell culture
- Must adhere to a surface to survive
- Form monolayers e.g. cells derived from
different tissues (breast, liver) - Growth is limited by surface area
- Will cease proliferating once they become
confluent (completely cover the surface of cell
culture vessel) - Cells are dissociated enzymatically or
mechanically from surface
What is the purpose of culture vessels?
provide a contamination barrier to protect the cultures from the external environment while maintaining the proper internal environment
What does the cells vessels do for anchorage-dependent cells?
provide a suitable and consistent surface for cell attachment
List the types of culture vessels
cell culture dishes
multiwell plates
flaska
What is the main reasons for surface coatings?
it is to give something for the cell line to attach to
make the palate more hydrophilic
What are some effects of biological contamination?
They compete for nutrients with host cells
* Secret acidic or alkaline by-products that cease the
growth of the host cells
* They also produce H2O2 which is directly toxic to
cells
What is one way that is used to prevent contaminates by different microorganisms?
Why is this not always recommended?
adding different antibiotics
it may help develop resistant microorganisms
What are the two most common cell types used for biotherepeutic proteins?
CHO (hamster)
murine (mouse)
Why are CHO cells used?
PTMs are similar to humans (glycostylation)
reduced susceptibility to certain viral infections
grow in suspension cultures
serum free chemically defined media
allows gene amplification
high productivity
highly tolerant to changes in pH, Oxygen levels, pressure and temperature
How to get protein out?
plants –> seeds
cow –> Milk
Chicken –> eggs
Define transgenesis
process of introducing foreign or exogenous DNA into an animal’s genome
Why transgenesis?
Improve genetic features of domesticated Animals
*Provide animal models for study of human diseases
*Pharming using farm animals for production of human
pharmaceuticals
*Study gene regulation and development of animals
Transgenic animals as bioreactors
Whole animals can serve as bioreactors to produce proteins
* Gene for a desired protein (Drug) is introduced via transgenics to the target cell
* By using cloning techniques, cell is raised to become an adult animal
* Produce milk or eggs that are rich in the desired prot
Explain retrovirus mediated transgenesis
infecting mouse embryos with retroviruses before the embryos are implanted
size of transgene is limited
Explain pronuclear microinjection
introduces the transgene DNA at the earliest possible stage of development of the zygote
DNA is injected directly into nucleus of egg or sperm
Why express rProtein in Milk?
Easy to purify - few other proteins in milk
* Doesn’t harm transgenic animal- no change in physiology
* rProtein is authentically modified post-translationally
* Large quantities
* Renewable source
What is Atryn?
it is an anti blood clotting protein derived from goats on this farm (antithrombin)
it is produced from the mammary glands of transgenic goats and harvested from their milk
it is the first drug made from genetically engineered animals approved by FDA