For determination of optimal pH at room temperature 100 mM Tris HCl buffer at a range of 6 10 was applied, whereas the range 4 6 was measured in 10 mM acetic acid/acetate buffer.
50 mM acetate buffer for pH range 4 6, 50 mM phosphate buffer for pH range 6 7, and 50 mM Tris HCl buffer for pH range 7 10 at 55 °C for 1 h.
For pH optimum determination, 50 mM citric acid was used for pH range of 4-6, 50 mM phosphate buffer for pH range of 6-8 and 50 mM Tris buffer for pH range of 8-9.
For pH stability assays, the purified enzymes were diluted (1 : 2 v/v) in 0.05 M glycine-HCl buffer from pH 1.6 to 2.5 and McIlvaine buffer for pH range from 3.0 to 7.0.
Graded buffer quality, as quantified by threading dislocation density (TDD) measurements, was investigated for a range of different graded buffer designs and growth parameters.
They were simplified and best solved using spline collocation to predict product distributions for a range of operating and initial conditions e.g. initial pH values and buffer concentrations.
RNase H2, aliquots of the enzyme were incubated at 95°C in Mg Cleavage Buffer for times ranging from 0 to 90 minutes before performing a cleavage activity assay.
In order to minimize plate-to-plate variation, each plate contained three replicates of sugar standards in buffer for the linear range of the DNS assay (0, 0.5, 1.0, 1.5, 2.0 and 3.0 mg/mL glucose or 0, 0.5, 1.0, 1.5, 2.0 and 2.5 mg/mL xylose).
