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UNIVERSITY OF EAST ANGLIA
School of Pharmacy
Main Series UG Examination 2012-13
PHARMACEUTICAL MICROBIOLOGY
PHAB2HH1
Time allowed: 2 hours
Part ONE.
Answer ALL questions. For each question, there is ONE correct answer. Use the
answer sheet provided for ALL your answers.
Part TWO.
Answer THREE of the FOUR questions. Write each answer in a SEPARATE answer
book.
The mark allocation for the paper is:
 Part ONE carries 40% of the total mark
 Part TWO carries 60% of the total mark
Graph paper for Q 34 will be provided.
This paper consists of 12 pages in total.
Notes are not permitted in this examination.
Do not take this question paper out of the examinations room.
Do not turn over until you are told to do so by the Invigilator.
(PHAB2HH1)
Copyright of the University of East Anglia
Module Contact: Dr Sheng Qi, PHA
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PART ONE
1.
Which of the following statements is TRUE?
The host for the causative agent of toxoplasmosis is the:
A)
B)
C)
D)
E)
Cat
Dog
Bird
Horse
Cow
2.
Which of the following statements about endogenous retroviruses is FALSE?
A)
E)
Endogenous retroviruses are derived from ancient infections of germ cells in
humans, mammals and other vertebrates
Human endogenous retroviruses comprise around 5-8% of the human
genome
They are passed on to the next generation in the form of proviruses
Endogenous retroviruses have been linked with some autoimmune disease
like multiple sclerosis
Endogenous retroviruses are the causative agent of chickenpox
3.
Which of the following statements about prions is FALSE?
A)
B)
C)
D)
E)
Prions cause transmissible spongiform encephalopathies
Prions can be transmitted via tissue transplants
Prions do cause inflammation in the brain of infected patients
Prions consist solely of protein
Prions have a long incubation period before the onset of disease
4.
Which of the following statements about fungi is FALSE?
A)
B)
C)
D)
E)
Fungi are composed of filaments called hyphae
Fungi have cell walls composed of chitin
Fungi have a unique method for lysine synthesis
The cell membrane of fungi contains ergosterol
Fungi have flagella to move towards food sources
5.
Which of the following statements about viruses is TRUE?
A)
B)
C)
D)
E)
All viruses contain DNA as their genetic material
All viruses have a cytopathic effect on infected cells
Some viruses can integrate into the human genome after infection
Some viruses can replicate outside a host cell
All viruses have an envelope
B)
C)
D)
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6.
Which of the following statements about pyrogens is FALSE?
A)
B)
C)
D)
E)
Endotoxins are a type of pyrogens
Pyrogens will elicit a rise in body temperature when injected into a mammal
The physiological effect of pyrogens depends on the route of administration
The LAL test is a very sensitive test to detect pyrogens
Pyrogens can be removed from liquids by boiling the solution for 15 minutes
7.
Which of the following statements about Staphylococcus aureus is TRUE?
A)
B)
C)
D)
E)
They are Gram negative bacteria
They are important for the production of yoghurt
They can cause food-poisoning
They live on skin and nasal membranes
They can cause dental plaque
8.
Which of the following statements about Chlamydia trachomatis is FALSE?
A)
B)
C)
D)
E)
Chlamydia trachomatis is a leading cause of blindness
Chlamydia trachomatis are unable to produce enough ATP to survive outside
of a host cell
A Chlamydia trachomatis infection often shows no symptoms
Chlamydia trachomatis is classified as a sexually transmitted disease
Chlamydia trachomatis lacks a cell wall
9.
Which of the following statements about Gram positive bacteria is TRUE?
A)
B)
C)
D)
E)
They have a periplasmic space which contains enzymes that can hydrolyse
penicillin
They contain lipopolysaccharides in their outer membrane
They will show a red colouring after a Gram stain
They are no susceptible to lysozyme
They have a thick peptidoglycan layer
10.
Which of the following statements about bacterial metabolism is TRUE?
A)
B)
C)
D)
E)
Chemotroph bacteria use chemical reactions to cover their energy needs
Auxotroph bacteria need only one organic substance as nutrients
Lithotroph bacteria use an organic compound as their hydrogen donor
Autotroph bacteria use an organic compound as their carbon source
Heterotroph bacteria use an inorganic compound as their hydrogen donor
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11.
Which of the following statements about obligate anaerobe bacteria is TRUE?
A)
B)
C)
D)
E)
They will only grow in the presence of oxygen
They do not tolerate any oxygen
They tolerate oxygen, but do not need it
They produce oxygen
They have a symbiotic relationship with algae
12.
Which of the following statements about transformation is TRUE?
A)
B)
Transformation is the injection of DNA into bacteria via bacteriophages
During transformation, bacteria pick up fragments of DNA from the
environment
Transformation is the exchange of DNA between two bacteria via a sex pilus
During transformation, bacteria start to produce viral particles
Transformation occurs only in bacteria when they have run out of nutrients
C)
D)
E)
13.
Which of the following is NOT an appropriate agent for use as a disinfectant in
aseptic production units?
A)
B)
C)
D)
E)
Ethyl alcohol
Methyl alcohol
Sodium dichlorisocyanurate
Chlorine gas
Hydrogen peroxide
14.
Which of the following would be an appropriate agent for the eradication of a
bacterial spore contamination within an aseptic production unit?
A)
B)
C)
D)
E)
Ethanol
Chlorhexidine
Peracetic acid
Triclosan
Chlorhexidine
15.
Which of the following properties should be considered when choosing a
preservative for an eye drop formulation?
A)
B)
C)
D)
E)
Sporicidal activity
Antibacterial activity at low pH
Volatility
Aqueous solubility
Activity against Pseudomonas aeruginosa
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16.
After performing a Gram stain you identify round shaped prokaryotic cells that
stain violet in colour. From this you can conclude which of the following?
A)
B)
C)
D)
E)
The bacterial cells are Gram positive rods
The bacterial cells are Gram positive cocci
The bacterial cells are Gram negative rods
The bacterial cells are Gram negative cocci
The cells are Gram positive filamentous bacteria
17.
Which of the following tests that can be used in the monitoring of clean room
environments assesses the viability of microorganisms?
A)
B)
C)
D)
E)
The Gram stain
The spore stain
Settle plate sampling
The DOP challenge test
Airflow velocity test
18.
Which of the following terms refers to a specific procedure used to prevent
unwanted microorganisms from contaminating a drug preparation?
A)
B)
C)
D)
E)
Disinfectant technique
Sterilising technique
Sanitising technique
Aseptic technique
Autoclave technique
19.
Which of the following statements concerning the advantage of isolators over
laminar air flow cabinets is FALSE?
A)
B)
C)
D)
E)
Non sterile clothing can be used by operators in isolators
The transfer hatch in an isolator can include a time interlock
Negative pressure isolators provide near perfect operator protection
Isolators must be sited in a minimum grade B environment
An isolator provides a total barrier to the external environment
20.
Which one of the following statements concerning the disadvantage of
isolators over laminar airflow cabinets is FALSE?
A)
B)
C)
D)
E)
They are uncomfortable – poor ergonomics for operators
They are more difficult to clean
It is more difficult to get equipment in & out of isolators
They are more expensive than conventional laminar air flow cabinets
The operators in an isolator need to work up close to the HEPA filter
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21.
Which of the following statement is FALSE?
A clean room (e.g. for an isolator-based aseptic activity) has the following
design features:
A)
B)
C)
D)
E)
No cracks and crevices
Easily cleaned smooth surfaces
A HEPA air supply
Access via a Grey / White changing room
Negative pressure room air
22.
Which of the following statements is FALSE?
Clean room hatches (linking a clean room to a support room):
A)
B)
C)
D)
E)
Must be flush fitting on the clean side
Must have doors which interlock so that both sides cannot be opened
simultaneously
Must be completely air tight
Must be easy to clean
Should preferably have glass doors
23.
Which of the following statements about sterilised medicines is FALSE?
A)
B)
C)
D)
E)
The medicine must be packaged in a sealed container
The medicine may be sterilised by filtration
The medicine can be sterilised using heat
The medicine is sterilised in its final sealed container
The medicine must not contain micro-organisms prior to sterilisation
24.
Which of the following is not a pharmacopoeal grade of water?
A)
B)
C)
D)
E)
Purified water in containers
Water for injections in bulk
Sterile water for injections
Potable water
Water BET
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25.
Which of the following statements is TRUE concerning the F0 concept?
A)
B)
Escherichia coli is used as a standard when discussing the F0 concept
The BP states that a sterilisation process must have a F0 value of not less
than 6
The F0 concept ignores the heating-up and cooling-down parts of the
sterilisation cycle
The F0 value is the time it takes at 115C to completely eradicate bacteria
from a product
The F0 concept allows prediction of the time required at a specific temperature
to produce a specific reduction in bioburden
C)
D)
E)
26.
Which one of the following statements is FALSE concerning the Z value of a
sterilisation process?
A)
Z is defined as the "the change in temperature required to cause a 10-fold
change in the D value"
Z values are different for different micro-organisms
Z values tend to be around 1 to 3C in the temperature range 100 to 130C
Z values can be used to predict the effect of different sterilisation
temperatures on the rate of kill of micro-organisms
Z values must be used in conjunction with D values
B)
C)
D)
E)
27.
Which one of the following is NOT an advantage of using ionizing radiation as
a method of sterilisation?
A)
Ionizing radiation is a powerful technique for inactivating various types of
micro-organisms
Ionizing radiation is effective against a large number of different types of
bacteria, yeasts, moulds and some viruses
Ionizing radiation can be used for thermo-labile samples
Ionizing radiation is a terminal technique
Ionizing radiation removes the non-viable microbial material and pathogens
from the sample
B)
C)
D)
E)
28.
Which one of the following types of medicinal products can be sterilised using
dry heat sterilisation?
A)
B)
C)
D)
E)
Injections containing thermally liable drug
Disposable syringes
Metal instruments
Wound irrigations
Eye ointments
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29.
Which of the following statements is FALSE concerning validation in
pharmaceutical manufacturing?
A)
It is necessary to prove that any procedure, process or system leads to the
expected result
It is very important for computerised systems
It can determine the level of sterility assurance for an aseptic fill process
It is an alternative to routine quality control
It is equally applicable to hospital pharmacy manufacturing as for industrial
scale
B)
C)
D)
E)
30.
Which of the following statements concerning filtration sterilisation is FALSE?
A)
B)
C)
D)
E)
Filtration sterilisation is a terminal sterilisation method
Depth filter is absolutely retentive
Screen filters are commonly made of cellulose acetate
Filtration method often cannot remove virus
Filtration can be used to sterilise thermolablie products
END OF PART ONE
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PART TWO
31.
Answer ALL parts: (a), (b) (c) and (d).
a)
The growth of a bacterial culture is described by the following formula:
G= t/(3.3xlog10(b/B))
where:
G = generation time (time for the cells to divide)
t = time interval in hours or minutes
B = number of bacteria at the beginning of a time interval
b = number of bacteria at the end of the time interval
What is the generation time in minutes of a bacterial population that increases
from 8 cells to 20,000 cells in 16 hours of growth? Show all your workings.
[30%]
b)
Use the formula above and calculate how many bacteria will be there after 12
hours, if 3 bacteria grow with a generation time of 23 minutes. Show all your
workings.
[30%]
c)
In the laboratory, you are given a vial containing a bacterial suspension. The
total volume of this suspension is 20 mL. Your task is to find out how many
bacteria are in this 20 mL suspension. Therefore you plate 0.4 mL of a 10-6
dilution of this suspension on a suitable nutrient plate and incubate overnight
at a suitable temperature. The next day you count 53 colonies on the nutrient
plate. How many bacteria were present in the 20 mL of your stock suspension
initially?
[20%]
d)
With the aid of an appropriate diagram show a typical growth curve for
Bacillus anthracis. Include in your diagrams details about what will happen if
nutrients run out in the solution.
[20%]
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32. Answer ALL parts: (a), (b) and (c).
Malaria is a tropical disease which accounts for 1-3 million deaths per year.
a)
Describe which pathogens cause malaria and with the aid of an appropriate
diagram explain the differences in the disease symptoms they cause.
[25%]
b)
With the aid of an appropriate diagram explain in detail how the parasite
proliferates and how it infects mankind.
[50%]
c)
Evolutionary pressure on our genome means that some mutation are the
cause of disease but at the same time they can be beneficent in preventing
infections with parasites. Describe TWO (2) such mutations and how they
affect the people when they are present in the genome.
[25%]
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33.
Answer BOTH parts: (a) and (b).
a) Define the term “pharmaceutical preservative”. Describe and discuss the
properties of an ideal pharmaceutical preservative.
[50%]
b) Describe the British Pharmacopoeial test for the “Efficacy of Antimicrobial
Preservation”.
[50%]
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34.
Answer ALL parts: (a), (b), (c) and (d).
A new intramuscular injection formulation of Drug X is sterilised using autoclave at
121°C for killing Soccibalia toralia spores. The viable count of Soccibalia toralia
spores measured at specified time intervals are shown in the table below.
Time after start of
process (minutes)
1
3
5
7
Number of viable micro-organisms
(cfu / mL)
3.63 x 106
4.02 x 104
5.26 x 102
3.12 x 100
a)
Explain the terms ‘sterility’ and ‘SAL’.
[10%]
b)
Describe the advantages and disadvantages of steam sterilisation, e.g.
autoclave.
[20%]
c)
It is known that the Z value of the Soccibalia toralia spores is 5°C. Use an
appropriate graphical method (graph paper is supplied) to calculate the
viable count in the same product after 18 minutes of sterilisation, if it was
processed at 116°C.
[40%]
d)
Calculate how long it would take to reduce the bioburden of Soccibalia
toralia spores in this formulation from 107 to 101 cfu/mL using a sterilisation
process at 126°C.
[30%]
END OF PAPER
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