Figure 4

Urease activity of mutants. Results of urease assays with wild type, mutants and complemented mutant as noted at bottom. Urease activity is expressed on the Y-axis as μmoles of urea hydrolyzed per minute. Results are the mean of 3 independent assays and error bars denote standard deviation. Urease activity was undetectable in ureC mutant and ure operon mutant.