FIG. 6.
Urease specific activities in S. salivarius 57.I and the UreMQO-deficient strain growing in BHI-KPB, BHI, and BHI-HCl containing 0 to 100 μM NiCl2. The specific activities are expressed as nanomoles of urea hydrolyzed per minute per milligram of protein. The values shown are averages from multiple reaction sets from three independent samples. For each value reported, separate reaction sets with various times and cell quantities, which fell within the linear ranges of the standard curve, were used. All reactions were performed in triplicate. N.D., not detectable.