TABLE 1.
NAE hydrolysis activity of mutant proteins expressed in E. coli
Proteins affinity purified from E. coli were reacted with 14C radiolabeled NAE12:0, NAE16:0, or NAE18:0. Specific activities were calculated based on radioactivity of the products formed. Values are shown as mean ± S.D. of triplicate measurements. For each NAE substrate, enzyme activities relative to wild-type AtFAAH without mutation (100%; WT) are indicated under “relative activity.”
| Enzymes | Specific activity |
Relative activity |
||||
|---|---|---|---|---|---|---|
| NAE12:0 | NAE16:0 | NAE18:2 | NAE12:0 | NAE16:0 | NAE18:2 | |
| μmol h−1mg−1 | % | |||||
| WT | 117 ± 8 | 134 ± 10 | 139 ± 8 | 100 | 100 | 100 |
| K205A | 0.06 ± 0.01 | 0.07 ± 0.02 | 0.10 ± 0.02 | 0.05 | 0.05 | 0.07 |
| S281A/ | 0.08 ± 0.01 | 0.08 ± 0.01 | 0.09 ± 0.01 | 0.07 | 0.06 | 0.06 |
| S282A | ||||||
| S305A | 0.09 ± 0.02 | 0.11 ± 0.02 | 0.15 ± 0.01 | 0.08 | 0.08 | 0.11 |
| R307A | 0.16 ± 0.03 | 0.21 ± 0.03 | 0.34 ± 0.05 | 0.14 | 0.16 | 0.24 |
| S360A | 119 ± 7 | 145 ± 12 | 152 ± 11 | 102 | 108 | 109 |