Brazzein (Brz) is a member of sweet-tasting protein containing four disulfide bonds. It was
reported as a compact and heat-resistant protein. Here, we have used site-directed
mutagenesis and replaced a surface-exposed alanine with aspartic acid (A19D mutant),
lysine (A19K mutant) and glycine (A19G mutant). Activity comparisons of wild-type (WT) and
mutants using taste panel test procedure showed that A19G variant has the same activity as
WT protein. However, introduction of a positive charge in A19K mutant led to significant …