Characterization of a new lysine decarboxylase from Aliivibrio salmonicida for cadaverine production at alkaline pH

In this study, a new LDC from Aliivibrio salmonicida (AsLdc) was discovered, expressed, and characterized. Compared to the LDCs from Escherichia coli, LdcC and CadA, the latter was frequently used for cadaverine production, the purified AsLdc showed much higher activities at alkaline pH 7.0–8.5, for instance, 205.1U/mg at pH 7.5 with 10μg/mL enzyme, in comparison to 68.3 and 51.5U/mg for CadA and LdcC, respectively. The activities of AsLdc and CadA correlated well with the proportions of decamers at the pH range of 5.0 to 8.5. AsLdc with a melting temperature of 79°C was more thermostable than CadA (73.6°C). When used for whole-cell biotransformation of L-lysine to cadaverine at pH 7.5, AsLdc completed the transformation within 7h while the CadA did only 82.8%. These results indicate the high potential of the new AsLdc for the industrial production of cadaverine. Graphical abstract
Source: Journal of Molecular Catalysis B: Enzymatic - Category: Biochemistry Source Type: research