Cicer arietinum GRP1 and GRP2 are rich in glycine interposed with histidine and tyrosine. In order to study whether or not these proteins bind Cu 2+ , circular dichroism (CD) and nuclear magnetic resonance (NMR) were measured for three synthetic peptides corresponding to sections of the protein's sequences including 1, N 1 Y 2 G 3 H 4 G 5 G 6 G 7 N 8 Y 9 G 10 N 11 , where all peptides were chemically blocked with an acetyl group at the N-terminus and an -NH 2 group at the C-terminus. The visible CD spectra for 1 showed a positive peak near 590 nm not at pH 6.0 but pH 7.4 in the presence of copper ions. The Cu 2+ binding induced a drastic change in the far-UV CD spectra, showing the occurrence of large conformation changes. In the 2D TOCSY NMR spectra at pH 7.4, the addition of small amounts of CuSO 4 caused a significant broadening of proton resonances of not only His4 but also Gly5, Asn8 and Asn11. CD titration experiment suggested that NYGHGGGNYGN including one repeat unit comprises the fundamental Cu 2+ binding unit.