Biochemical characterization of a sphingomonad isolate from the ascocarp of white truffle (Tuber magnatum Pico)

Available information on bacteria that influence the economically important white truffle (Tuber magnatum Pico) life cycle is scarce. From the ascocarp of white truffle we isolated a strain TMG 022C, capable for growth in nitrogendepleted conditions and assimilation of mannitol and trehalose. According to 16S rDNA sequence phylogeny, the strain was closely related to Sphingobium amiense. The strain had the ability to perform ammonification, reduce nitrate and solubilize Ca3(PO4)2, produce chitinase, lipase, phospholipase and β-glucanase, but not cellulase, pectinase, protease and siderophores. The results suggest that Sphingobium sp. TMG 022C could have an influence on the Tuber magnatum life cycle through improved mycelium nutrition and ascocarp decomposition