Assembly of the peptidoglycan later of bacterial cell walls is a validated target for anti-bacterial agents: the late transpeptidation and transglycosylation steps are inhibited by the penicillin and the vancomycin groups of antibiotics respectively. There is considerable interest in the development of novel inhibitors of peptidoglycan biosynthetic enzymes, but to date few new lead compounds have been generated against earlier steps in the pathway. We will use Small Angle Neutron scattering to determine the low resolution structure of three proteins, MurM, FemA, and FemX from S pneumoniae and S aureus that catalyse the the transfer of glycine from activated tRNA intermediates to peptidoglycan pre-cursors. These preliminary experiments will also lay the ground work for future experiments to determine tRNA-protein complex structures via contrast variation SANS.