IMMOBILIZATION OF LEVANSUCRASE ON CALCIUM-PHOSPHATE GEL STRONGLY INCREASES ITS POLYMERASE-ACTIVITY

The catalytic properties of levansucrase bound to hydroxyapatite were studied as a possible model for enzyme behaviour when associated in vi vo to matrices such as the cell wall of bacteria or tooth surfaces. Th e activity of the immobilised enzyme was mainly directed towards its p olymerase activity. The yield of levan reached 85%. The k(cat) of the enzyme for sucrose transformation was increased and the K(m) for this substrate was unmodified. These properties allow the design of a syste m for the large-scale production of high-molecular-weight branched-cha in levan in vitro in high yield.