Catalysis of the reaction: L-aspartate + fumarate = alpha-iminosuccinate + succinate.
Source:PMID:20149100
Comment
This is based on the finding that L-aspartate oxidase (NadB) of E. coli preferentially uses fumarate as the electron acceptor and does so under anaerobic conditions. The same enzyme uses oxygen as the electron acceptor under aerobic conditions. The EC conflates the two reactions in EC:1.4.3.16 (as they are catalyzed by the same enzyme).