Table 1 Specific activity and reaction specificity of B. subtilis WT LS and selected mutants
Reaction specificity(%): sucrose (120 g/L) | Reaction specificity (%): sucrose (120 g/L)/xylose (120 g/L) | ||||||
|---|---|---|---|---|---|---|---|
Enzyme | Specific activity (U/mg protein) | Hydrolysis | Trans-fructosylation | Hydrolysis | Trans-fructosylation to sucrose | Trans-fructosylation to xylose | Product synthesized from sucrose (120 g/L) |
WT LS | 160.5 (± 6.0) | 52. | 547.5 | 21.3 | 18.1 | 60.6 | Levan with molecular weight bimodal distribution |
R360K | 171.2 (± 7.0) | 88.3 | 11.7 | 37.0 | 5.3 | 57.7 | Oligosaccharides and low amounts of high molecular weight levan |
Y429N | 1.5 (± 0.9) | 97.3 | 2.7 | 49.3 | 9.6 | 41.1 | Oligosaccharides |
Invertase | 878.3 (± 6.8) | 98.6 | 1.4 | 0.0 | 0.0 | 0.0 | - |