Molecular Biotechnology. Bernard R. Glick

that have been used to increase proper folding and secretion of recombinant proteins from yeast cells.

      16. Discuss the salient features of a P. pastoris high-expression integrating vector system. How has P. pastoris been “humanized”?

      17. What are baculoviruses?

      18. Describe a strategy that can be used to insert a target gene into the baculovirus genome for expression in insect cells.

      19. Describe the main features of an extrachromosomal mammalian-cell expression vector.

      20. Why are yields of recombinant proteins produced by mammalian cells in large bioreactors generally low? How can yields be improved?

      21. What is chromatin, and how does it affect gene expression? Describe some of the strategies that have been developed to increase expression levels of a target gene that is integrated into a chromosome of a eukaryotic host cell.

      22. You have produced a recombinant enzyme for an industrial application but have found that the protein is unstable at moderately high temperatures. Describe how you would increase the stability of the enzyme. Assume that you have determined the DNA sequence of the gene encoding the enzyme and the structure of the enzyme.

      23. How can unusual amino acids be incorporated into proteins, thereby producing an altered form of the target protein?

      24. You have produced a recombinant enzyme for an industrial application but have found that the catalytic activity is low. Describe how you would increase the activity of the enzyme if the DNA sequence of the gene was known but the structure of the enzyme was not determined.

      25. Outline two ways in which DNA shuffling may be used to generate hybrid genes.

      26. How would you engineer streptokinase so that it was less sensitive to proteolytic digestion?

      27. How can the gene(s) encoding a Fab fragment of a monoclonal antibody be modified so that the specificity of the antibody is altered?