Sample: Concentrated Streptococcus thermophilus cells
In this instance, the user was looking to assess enzymatic activity. You may substitute another buffer which is appropriate for your application.
Protein content was measured within the total cell extract by Bradford assay. Enzyme activities (β-galactosidase and lactate dehydrogenase) were measured spectrophotometrically.
β-galactosidase (a) and lactate dehydrogenase (b) activities of S. thermophilus wild-type cells (white bars) and A19(Δppc;ΔcarB) mutant cells (grey bars) grown in enriched CO2 or N2 atmosphere.