Two types of phytases (histidine acid phytase and β-propeller phytase) in Serratia sp. TN49 from the gut of Batocera horsfieldi (coleoptera) larvae.

Microbial phytases play a major role in the mineralization of organic phosphorous, especially in symbiotic plants and animals. In this study, we identified two types of phytases in Serratia sp. TN49 that was harbored in the gut of Batocera horsfieldi (Coleoptera) larvae. The two phytases, an acidic histidine acid phosphatase (PhyH49) and an alkaline β-propeller phytase (PhyB49), shared low identities with known phytases (61% at most). PhyH49 and PhyB49 produced in Escherichia coli exhibited maximal activities at pH 5.0 (60°C) and pH 7.5-8.0 (45°C), respectively, and are complementary in phytate degradation over the pH range 2.0-9.0. Serratia sp. TN49 harboring both PhyH49 and PhyB49 might make it more adaptive to environment change, corresponding to the evolution trend of microorganism.