Abstract
Microplusin is a copper and iron chelating peptide, present in the cattle tick Riphicephalus (Boophilus) microplus. It has a globular structure, arranged in five ±-helices and is rich in histidine and cysteine amino acids residues. The histidines H-1, H-2 and H-74 were among the possible amino acids involved in forming the binding site for copper. In addition to its chelating ability, mic…