Amino acids and peptides. XXVI. Synthesis of Agaricus bisporus metallothionein and related peptides and examination of their heavy metal-binding properties.

A pentacosapeptide corresponding to the entire amino acid sequence of Agaricus bisporus metallothionein (MT) and related cysteine-containing peptides were prepared by the conventional solution method and their heavy metal-binding properties were examined. The Cu2(+)- or Cu(+)-binding activities of various peptides were not greatly dependent on the peptide structure, so far as examined, although the pentacosapeptide, A. bisporus MT, exhibited slightly higher binding activity than the other peptides. On the contrary, the Cd2(+)-binding activities of these peptides were fairly structure-dependent.