Advantages of cloning in yeast (S. cerevisiae) — Which statement(s) describe recognized benefits of using yeast as a eukaryotic host?
Correct Answer: All of the above
Introduction / Context:Yeast bridges bacterial ease and eukaryotic processing, making it a prime platform for biotechnology. It supports industrial-scale production, eukaryotic protein maturation, and large-fragment cloning, all of which are crucial in modern genomics and biopharma.
Given Data / Assumptions:
- S. cerevisiae and related yeasts are GRAS (generally recognized as safe) organisms in many applications.
- Secretory pathways in yeast can glycosylate and fold proteins.
- Yeast artificial chromosomes (YACs) can carry megabase-sized inserts.
Concept / Approach:Match each benefit to known yeast capabilities. Yeast can overexpress proteins using strong promoters, carry out N-linked glycosylation, and maintain large genomic inserts with YAC technology. Hence the inclusive option is correct.
Step-by-Step Solution:
Confirm protein overproduction with inducible/constitutive promoters (e.g., GAL1, PGK1, ADH1).Acknowledge secretory signal peptides enabling glycosylation and export.Recognize YACs for large DNA cloning compared with plasmids/cosmids.Verification / Alternative check:Industrial enzyme and vaccine subunit production in yeast validates options a and b; genome projects historically used YACs for physical mapping (option c).
Why Other Options Are Wrong:
- e: Incorrect because multiple advantages are real and documented.
Common Pitfalls:Assuming yeast glycosylation is identical to mammalian; patterns differ but still provide key eukaryotic modifications.
Final Answer:All of the above