The recently discovered translocation and assembly module (TAM) is a membrane protein complex found in Gram-negative bacteria that plays an important role in the assembly of key virulence proteins called autotransporters. The TAM spans the periplasmic space and is composed of two integral membrane proteins, TamA and TamB, which reside in the outer- and inner-membranes respectively. TamA belongs to the conserved Omp85 protein superfamily with members found in plants, protists, animals and bacteria. To reduce the incidence of bacterial pathogens developing resistance to antimicrobials, it is thought that by targeting bacterial components essential for virulence and not viability, may reduce selective pressure for resistant organisms. Inhibiting the function of TAM may prove a useful strategy for the defence against bacterial pathogens. We have determined the structure of the N-terminal domain of TamA by NMR, revealing a classical POTRA domain structure. Biochemical analysis demonstrates that POTRA 1 of TamA is essential for its interaction with TamB. Deletion of the last 7 residues of TamB (L1253-F1259) did not affect TAM complex formation however, it was found to be non-functional through Ag43 cell sedimentation experiments. Bioinformatic analysis revealed that the C-terminal of TamB resembles a b-signature motif found at the c-terminus of most outer membrane b-barrel proteins, including autotransporters. These insights into how the TAM complex is stabilised and functions will aid in the future design of antimicrobial therapeutics.