Fructanolytic and saccharolytic enzymes of Treponema zioleckii strain kT

Enzymes in the newly described rumen bacterium, Treponema zioleckii strain kT, capable of digesting Timothy grass fructan, inulin, and sucrose were identified and characterized. Two specific endolevanases and one non-specific β-fructofuranosidase were found in a cell-free extract. The molecular weight of the endolevanases were estimated to be 60 and 36 kDa, whereas that of β-fructofuranosidase, 87 kDa. The former of the specific enzymes was associated with the outer membrane, while the latter and the non-specific β-fructofuranosidase, with the periplasm or cytosol. The Km and Vmax for Timothy grass fructan degradation by endolevanase were 0.27% and 15.75 μM fructose equivalents × mg protein−1 × min−1, those for sucrose and inulin digestion by β-fructofuranosidase were 1.35 × 10−3 M and 1.73 μM hexoses × mg protein−1 × min−1 and 1.77% and 1.83 μM hexoses × mg protein−1 × min−1, respectively.