MPharm Master of Pharmacy Pharmaceutical Microbiology and Biotechnology 2 — Questions and Answers
Question 1: Which expression system is most commonly used for the production of recombinant therapeutic proteins requiring complex post-translational modifications like glycosylation?
- E. coli bacterial expression
- Yeast (Saccharomyces cerevisiae)
- Chinese Hamster Ovary (CHO) cell culture (Correct answer)
- Baculovirus insect cell system
Correct answer: Chinese Hamster Ovary (CHO) cell culture
CHO cells produce human-like glycosylation patterns essential for the safety, efficacy, and pharmacokinetics of therapeutic glycoproteins like monoclonal antibodies.
Question 2: What is the purpose of a 2-micron (2 µm) filter used in a downstream biopharmaceutical purification process?
- Sterile filtration of the final product
- Removal of whole cells and cell debris (Correct answer)
- Virus removal from protein solutions
- Endotoxin removal via charge interaction
Correct answer: Removal of whole cells and cell debris
Coarser depth and membrane filters in the 1–5 µm range are used in initial bioprocessing steps to remove whole cells and large debris before chromatography.
Question 3: Which chromatography technique is the primary purification step for monoclonal antibody (mAb) manufacturing?
- Ion exchange chromatography
- Protein A affinity chromatography (Correct answer)
- Hydrophobic interaction chromatography
- Gel filtration chromatography
Correct answer: Protein A affinity chromatography
Protein A affinity chromatography selectively captures IgG antibodies via the Fc region with high specificity and yield, achieving >95% purity in a single step.
Question 4: In pharmaceutical biotechnology, what is the role of biosimilars?
- Exact chemical copies of small-molecule generic drugs
- Biological products highly similar to an already-approved reference biologic with no clinically meaningful differences (Correct answer)
- Improved versions of originator biologics with new mechanisms of action
- Plant-derived alternatives to synthetic biologics
Correct answer: Biological products highly similar to an already-approved reference biologic with no clinically meaningful differences
Biosimilars are biological products approved via an abbreviated pathway demonstrating they are highly similar to a reference product with no clinically meaningful differences in safety, purity, and potency.
Question 5: What is the purpose of the Mycoplasma testing requirement for cell-culture-derived biopharmaceuticals per FDA guidelines?
- Mycoplasma testing verifies host cell DNA removal
- Mycoplasma are wall-less bacteria that can contaminate bioreactors and would pass standard bacterial sterility filters, making detection mandatory (Correct answer)
- The test measures mycoplasma toxin levels
- Mycoplasma testing is required only for viral vector products
Correct answer: Mycoplasma are wall-less bacteria that can contaminate bioreactors and would pass standard bacterial sterility filters, making detection mandatory
Mycoplasmas lack cell walls and pass through 0.22 µm sterilizing filters, making them a significant contamination risk in mammalian cell culture requiring dedicated testing.
Question 6: Which analytical technique is used to confirm the primary sequence and post-translational modifications of a recombinant therapeutic protein?
- UV-Vis spectrophotometry
- Peptide mapping with LC-MS/MS (Correct answer)
- Karl Fischer titration
- Dynamic light scattering
Correct answer: Peptide mapping with LC-MS/MS
Peptide mapping combined with LC-MS/MS digests the protein into fragments and identifies their sequences and modifications, confirming protein identity and structural integrity.
MPharm Master of Pharmacy Pharmaceutical Microbiology and Biotechnology 2
Which expression system is most commonly used for the production of recombinant therapeutic proteins requiring complex post-translational modifications like glycosylation?