This domain is found at the N-terminus of tetrahydrodipicolinate N-succinyltransferase (DapH) which catalyses the acylation of L-2-amino-6-oxopimelate to 2-N-succinyl-6-oxopimelate in the meso-diaminopimelate/lysine biosynthetic pathway of bacteria, blue-green algae, and plants [1]. The N-terminal domain as defined here contains three alpha-helices and two twisted hairpin loops [2].

1: Acyl group specificity at the active site of tetrahydridipicolinate N-succinyltransferase. Beaman TW, Vogel KW, Drueckhammer DG, Blanchard JS, Roderick SL; Protein Sci 2002;11:974-979. PMID:11910040

2: Three-dimensional structure of tetrahydrodipicolinate N-succinyltransferase. Beaman TW, Binder DA, Blanchard JS, Roderick SL; Biochemistry 1997;36:489-494. PMID:9012664