Small Differences in Gene Sequences Impact Invertase Activity and Specificity toward Fructans with Different Chain Lengths.

invertase is encoded by a family of closely related genes. To identify and understand the molecular basis for differences in substrate specificity, we examined 29 alleles from industrialstrains and cloned alleles with small sequence differences into an invertase-negative strain. Our study showed that an F102Y substitution in Suc-enzymes lowers yeast invertase activity toward fructo-oligosaccharides (FOS) by 36% and the specificity factor by 43%.