Evidence That Two ATP-Dependent (Lon) Proteases in Borrelia burgdorferi Serve Different Functions
Figure 6
Chaperone-like activity of rLon-1S714A, as determined by prevention of the aggregation of reduced insulin B-chain.
(A) Effect of rLon-1S714A on aggregation of reduced insulin B-chain in the absence of ATP (upper panel), in the presence of 4 mM ATP (middle panel), and in the presence of 10 mM ATP (lower panel). (B) Effect of wild-type rLon-1 and rLon-1S714A on reduced insulin as analyzed by Tris-tricine SDS-PAGE, followed by Coomassie blue staining. For the digestion, approximately 25 µg of rLon-1 and rLon-1S714A were incubated at 37°C for two hours with 150 µg of insulin, in the presence of 4 mM ATP. Each gel lane received 10 µl of the digestion mixture. Asterisk shows position of either rLon-1 or rLon-1S714A. Experiments shown are representative of two experiments in which similar results were obtained.