STRUCTURAL-ANALYSIS AND COMPARISON OF THE C-TERMINAL TRANSPORT SIGNAL DOMAINS OF HEMOLYSIN-A AND LEUKOTOXIN-A

NMR spectroscopy was used to study the structure of the C-terminal signal sequences of the bacterial toxins, hemolysin A(HlyA) and leukotoxin A (LktA), The two signals share little sequence homology; however, both can direct toxin transport,vith equal efficiency, We report here that in a membrane mimetic environment both peptides form two short non-interacting alpha-helices separated by a short loop, This higher order structure may be a common feature of C-terminal signals and may be required for interaction with the membrane associated transporter complex.