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The structural and NMR spectroscopic studies of the [Zn.sup.2} binding sites of human and rat [beta]-amyloid (1-28) fragments in water/sodium dodecyl sulfate micelles is demonstrated.

Neurological disorders of cognitive abnormalities, collectively known as neurodegenerative diseases imply the presence of excess misfiled proteins causing neuronal damage such as Alzheimer's and prion diseases, and Parkinson's diseases and amyotrophic lateral sclerosis. In all these disorders, copper-containing proteins that are normally soluble convert into insoluble aggregates by impaired copper homeostasis that can form intractable and frequently toxic deposits in brain, skeletal and muscular tissue, in the heart and the liver.

A study is conducted with the aim of further delineating the structure and stability of Cu(super II) complexes with monomeric, dimeric, and trimeric hexarepeats of chicken prion. It is shown that copper ions are very effectively bound by hexarepeat fragments of chicken prion, although not as effectively as found in the case of mammalian protein.

The synthetic peptide encompassing residues 106-126 of the human prion protein was considered for its binding properties toward copper(II), manganese(II) and zinc(II) at pH 5.7. The metal-peptide association was described by the paramagnetic effects of Cu(II) and Mn(II) upon 1D and 2D spectra, while Zn (II) was found to yield negligible effects upon any NMR parameter.

Research has been conducted on the lincomycin-copper(II) complex. The results of the (super)1 H and (super)13 C NMR studies of this complex which allow the structure and dynamics delineation of the complexes in water solutions are presented.

The structure and copper-binding mode of three peptides derived from the tandem repeat region of 'similar to prion protein' (StPrP-2) from the Japanese pufferfish Takifugu rubripes are investigated to examine if they bind Cu(II) as effectively as the mammalian prion protein. It is observed that the histidine imidazoles provide the anchoring site for copper with further amide nitrogen involvement depending on the peptide sequence and on pH, and the copper binding affinity increases from the shortest peptide to the longest one, corresponding to tandem repeats.