Polymerases involved in microbial fructan (levan, inulin, and fructo-oligosaccharide) production are known as microbial fructosyltransferases (levansucrases). Levan could be used in the culinary, pharmaceutical, medical, cosmetics, and textile industries. Microbial fructosyltransferase proteins are classified into seven phylogenetically related clusters that share the catalytic domain of the glycoside hydrolases 68...