Gene cloning and expression of a 3-ketovalidoxylamine C-N-lyase from Flavobacterium saccharophilum IFO 13984

In this study, we report the first functional cloning and heterogeneous expression of 3-ketovalidoxylamine C-N lyase (E.C. 4.3.3.1) from Flavobacterium saccharophilum IFO 13984. This gene is 1,098 bp in length and encodes a peptide of 366 amino acids. The recombinant C-N lyase was successfully overexpressed in E. coli, and its functional activity, degradation of 3-ketovalidoxylamine A, was confirmed by HPLC analysis. The sequence and phylogenetic analysis showed that the C-N lyase has no similarity with other amine lyases (E.C. 4.3.3) but has similarity with the conserved domain present in SusD and RagB. Thus, the C-N lyase may have a similar binding domain for sugar moieties with SusD/RagB. This genetic information may lead to improvements in C-N lyase function for industrial applications.