Direct cadaverine production from cellobiose using β-glucosidase displaying Escherichia coli

摘要

In this study, we demonstrate the one-step production of cadaverine (1,5-diaminopentane) from cellobiose using an Escherichia coli strain displaying β-glucosidase (BGL) on its cell surface. L-lysine decarboxylase (CadA) derived from E. coli and BGL from Thermobifida fusca YX (Tfu0937) fused to the anchor protein Blc from E. coli were co-expressed using E. coli as a host. The expression of CadA was confirmed by Western blotting and BGL activity on the cell surface was evaluated using pNPG as a substrate. Growth on cellobiose as the sole carbon source was also achieved. The OD600 value of the BGL and CadA co-expressing strain was 8.0 after 48h cultivation, which is higher than that obtained by growth on glucose (5.4 after 48h cultivation). The engineered strain produced cadaverine from cellobiose more effectively than from glucose: 6.1mM after 48h from 28 g/L of consumed cellobiose, vs. 3.3 mM from 20 g/L of consumed glucose.