Figure 7.

Growth and gas vesicle production of H. salinarum NRC-1 and the tbpD non-native expression mutant strains. (A) A comparison of growth curves for wild-type H. salinarum NRC-1 and the nonnative tbpD expression strain. Optical density measured at 600 nm (OD₆₀₀) is reported for two replicate flask growth cultures for each strain. Severe growth retardation is evident in the nonnative tbpD expression strain. (B) Growth versus gas vesicle production in wild-type cells and the nonnative tbpD expression mutant is shown as measured by OD₆₀₀ and median pixel intensity for the cellular population, respectively. An increase in gas vesicle production is noted in wild-type cells that is absent in the tbpD mutant.