fumarate + L-arginine => 2-(N(omega)-L-arginino)succinate
fumarate + l-arginine => 2-(n(omega)-l-arginino)succinate
fumarate + L-arginine => 2-(N(omega)-L-arginino)succinate
fumarate + l-arginine => 2-(n(omega)-l-arginino)succinate