As the two strands of the double helix are separated, the positive supercoiling interferes with the further unwinding of DNA. Which of the following enzyme makes a break in a strand of DNA to release the supercoiling and facilitate the replication to occur?

#Question id: 14317

#Section 5: Bioprocess Engineering and Process Biotechnology

system for manufacture of single-cell protein is Methylophilus methylotrophus. This organism is produced aerobically from methanol with ammonia as nitrogen source. The molecular formula for the biomass is CH _1.680_0.36N_0.22; these cells contain 6% ash. What is the maximum possible biomass yield from methanol?

#Question id: 14318

#Section 5: Bioprocess Engineering and Process Biotechnology

system for manufacture of single-cell protein is Methylophilus methylotrophus. This organism is produced aerobically from methanol with ammonia as nitrogen source. The molecular formula for the biomass is CH _1.680_0.36N_0.22; these cells contain 6% ash. If the actual yield of biomass from methanol is 42% the thermodynamic maximum, what is the oxygen demand?

#Question id: 14319

#Section 5: Bioprocess Engineering and Process Biotechnology

Both Saccharomyces cerevisiae yeast and Zymomonas mobilis bacteria produce ethanol from glucose under anaerobic conditions without external electron acceptors. The biomass yield from glucose is 0.11 g g^-1 for yeast and 0.05 g g^-I for Z. mobilis. In both cases the nitrogen source is NH₃. Both cell compositions are represented by the formula CH_1.80_0.5N_0.2. What is the yield of ethanol from glucose by Saccharomyces cerevisiae yeast?

#Question id: 14321

#Section 5: Bioprocess Engineering and Process Biotechnology

Both Saccharomyces cerevisiae yeast and Zymomonas mobilis bacteria produce ethanol from glucose under anaerobic conditions without external electron acceptors. The biomass yield from glucose is 0.11 g g-1 for yeast and 0.05 g g-I for Z. mobilis. In both cases the nitrogen source is NH 3. Both cell compositions are represented by the formula CH 1.800.5N0.2. Compare actual yield with theoretical maximum for Zymomonas mobilis bacteria ?

#Question id: 14322

#Section 5: Bioprocess Engineering and Process Biotechnology

Production of recombinant protein by a geneticallyengineered strain of Escherichia coli is proportional to cell growth. Ammonia is used as nitrogen source for aerobic respiration of glucose. The recombinant protein has an overall formula CH_I.550_0.31N_0.25. The yield ofbiomass from glucose is measured at 0.48 g g^-1; the yield of recombinant protein from glucose is about 20% that for cells. How much ammonia is required per gmol glucose?