... folding pathway: structure-based analysis of staphylococcal nuclease. Proteins: Structure, Function and Genetics 27, 171–183.15 Flanagan JM, Kataoka M, Fujisawa T & EngelmanDM (1993) Mutations ... Salmon testesDNA and some analytical grade chemicals such as EDTA,Tris ⁄ HCl, CaCl2, NaCl and mineral oil were obtained fromSigma (St Louis, MO, USA). Salmon testes DNA for theenzyme activity ... the wild- type protein and mutants E142O and K13 3A. Thermal analysis of protein unfoldingThe DSC curves of the wild- type protein and themutants K13 3A, E142O, W14 0A and W140O areshown in Fig. 3,...