Recombinant bacterial phytases to reduce environmental phosphate pollution

摘要

The interest in phytate-degrading enzymes has steadily increased in the last 10 years. Possible applications of phytases have been suggested in animal nutrition to increase mineral bioavailability and to decrease phosphate pollution in areas of intensive lifestock management and in human nutrition to increase mineral bioavailability and to provide humans with physiologically active phytate degradation products as well as in stimulating plant growth. Several bacterial phytases have been purified and extensively characterized. They exhibit differences in optimal hydrolysis conditions, pH as well as temperature stability, substrate specificity and the dephosphorylation pathway of phytate. The different properties of these enzymes may lead to different applications. For a biotechnological application, bacterial phytases have to be produced in high yield and purity by a relatively inexpensive system. Therefore, the corresponding genes have been isolated and over-expressed in different host organisms.