... led to the prediction that certain aminoacid(s) in the flexible segment stabilize the rest of the structure, in particular the key amino acid(s) locatedclose to this flexible segment. The tryptophan ... random coil. We can therefore postulatethat, when the segment beyond W140 was removed, the secondary structure of the protein disintegrated. Using the peak at 222 nm of the wild-type protein ... protein unfolding The DSC curves of the wild-type protein and the mutants K133A, E142O, W140A and W140O areshown in Fig. 3, with their thermodynamic parameterssummarized in Table 1. The calorimetric...