Tailoring fructooligosaccharides composition with engineered Zymomonas mobilis ZM4

Abstract

Zymomonas mobilis ZM4 is an attractive host for the development of microbial cell factories to synthesize high-value compounds, including prebiotics. In this study, a straightforward process to produce fructooligosaccharides (FOS) from sucrose was established. To control the relative FOS composition, recombinant Z. mobilis strains secreting a native levansucrase (encoded by sacB) or a mutated -fructofuranosidase (Ffase-Leu196) from Schwanniomyces occidentalis were constructed. Both strains were able to produce a FOS mixture with high concentration of 6-kestose. The best results were obtained with Z. mobilis ZM4 pB1-sacB that was able to produce 73.4±1.6 g L1 of FOS, with a productivity of 1.53±0.03 g L1 h1 and a yield of 0.31±0.03 gFOS gsucrose1. This is the first report on the FOS production using a mutant Z. mobilis ZM4 strain in a one-step process.