Figure 4.

Acetylesterase activity of AlgF and the putative acetylation complex. Enzyme activity was measured by hydrolysis of acetate from the pseudosubstrate ACC. Release of the 7-hydroxycoumarin-3-carboxylic acid fluorescent product was measured (λ_ex = 386 nm and λ_em = 446 nm). Values represent three technical replicates for three biological replicates. Red lines represent the mean. The reactions were performed with the addition of 2 mM ACC to 5 μM of each protein. Buffer contained 50 mM sodium Hepes pH 7.6 and 75 mM NaCl at 25 °C. ManA₁₀ denotes the addition of 1 mg/ml chemically synthesized polymannuronate decasaccharide. Statistical significance was determined using a one-way ANOVA test.