In principle, the NOG can also be coupled with the carbon-fixing Calvin-Benson-Bassham (CBB) cycle to achieve more efficient carbon conservation efficiency. To produce acetate directly from CO2, you engineered a phosphoketolase (PK) gene and an acetate kinase gene into a cyanobacterial strain to couple the CBB cycle with the NOG pathway.

(a) Assuming all CO2 will be used for acetate production, how many molecules of acetate can be produced from 6 molecules of CO2 in either the CBB-EMP pathway or the CBB-NOG pathway?

(b) You implemented the CBB-NOG design in wet lab research. However, instead of acetate production, you observed that cells ceased to grow under the light in the engineered cyanobacterial strain with PK overexpressed. Please explain possible reasons that could have caused this phenotype.

(c) What strategy do you propose to potentially solve the above problem so cells can grow under the light and produce acetate using the CBB-NOG pathway?