- Insertion mutation of the form I cbbL gene encoding ribulose bisphosphate carboxylase/oxygenase (RuBisCO) in Thiobacillus neapolitanus results in expression of form II RuBisCO, loss of carboxysomes, and an increased CO2 requirement for growth. Baker, S.H., Jin, S., Aldrich, H.C., Howard, G.T., Shively, J.M. J. Bacteriol. (1998)