Figure 4From: Expression of urease by Haemophilus influenzaeduring human respiratory tract infection and role in survival in an acid environmentUrease 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.Back to article page