A novel approach to chemical microarray using ketone-modified macromolecular scaffolds: application in micro cell-adhesion assay.

This paper describes a novel strategy for the preparation of chemical microarrays using macro-molecular scaffolds. The macromolecular scaffolds are first functionalized with ketone groups and compounds of interest containing an aminooxy group are conjugated onto the ketone-modified scaffolds through a chemoselective oxime ligation. The conjugate mixtures are then spotted directly onto a plastic or glass surface to form compound microarrays.

Xenobiotic-induced loss of tolerance in rabbits to the mitochondrial autoantigen of primary biliary cirrhosis is reversible.

Previous work has demonstrated that immunization of rabbits with the xenobiotic 6-bromohexanoate coupled to BSA breaks tolerance and induces autoantibodies to mitochondria in rabbits. Such immunized rabbits develop high-titer Abs to pyruvate dehydrogenase complex (PDC)-E2, the major autoantigen of primary biliary cirrhosis. In efforts to map the fine specificity of these autoantibodies, rabbits were immunized biweekly with 6-bromohexanoate-BSA and screened for reactivity using a unique xenobiotic-peptide-agarose microarray platform with an emphasis on identifying potential structures that mimic the molecular image formed by the association of lipoic acid with the immunodominant PDC-E2 peptide.

Protein and Chemical Microarrays-Powerful Tools for Proteomics.

In the last few years, protein and chemical microarrays have emerged as two important tools in the field of proteomics. Specific proteins, antibodies, small molecule compounds, peptides, and carbohydrates can now be immobilized on solid surfaces to form high-density microarrays. Depending on their chemical nature, immobilization of these molecules on solid support is accomplished by in situ synthesis, nonspecific adsorption, specific binding, nonspecific chemical ligation, or chemoselective ligation.

N-to-C solid-phase peptide and peptide trifluoromethylketone synthesis using amino acid tert-butyl esters.

Solid-phase peptide synthesis in the N-to-C direction, opposite to the classical C-to-N direction of peptide synthesis, provides the synthetically versatile C-terminal carboxyl group for further modification into C-terminally modified peptide mimetics. These are of general interest as potential bioactive agents, particularly as protease inhibitors. Elaboration of peptide mimetics on the solid-phase would facilitate synthesis of peptide mimetic combinatorial libraries.