heat-denaturation of tryptophan synthase alpha-subunit from e. coli and two mutant proteins ( glu 49 leads to gln or ser ; called gln 49 or ser 49 , respectively ) has been studied by the scanning microcalorimetric method at various ph , in an attempt to elucidate the role of individual amino acid residues in the conformational stability of a protein .
C0017797
gln
C0002520
amino acid