Wild-type at all temperatures (30, 37, and 42 ) (Fig. 1 and supplemental Fig. S2). These results indicate that stability of 32 in vivo does not always reflect its direct susceptibility to proteases and that the high stability of I54A 32 in vivo is attributed to some intracellular state of 32. Stable 32 Mutants Show Reduced Affinity for DnaJ--The above results showed that other factors in addition