The objectives of this research are twofold, First, we plan to continue wit the development of the chemistry of solid phase peptide synthesis. This wil include the design and preparation of some new polymer supports and studies on their physical and chemical properties. The rates of mass transfer or reagents into the polymer beads and the kinetics of peptide-forming reactions will be examined. The use of mass spectrometry to detect trace amounts of byproducts will be further developed and chemical and physical methods to eliminate these low-level side reactions will be examined. Second, we plan to apply these synthetic techniques to the study of peptide and small proteins of biological interest. Total and partial syntheses of such compounds and of selected analogs are designed to answer questions about mechanisms and modes of action that are difficult to answer by studie on the naturally occurring peptides and proteins themselves. The target molecules will include the antibacterial peptides cecropin and sarcotoxin and their pro- and preproforms, and the hypervariable domains of immunoglobulins. We also plan to define the substrate requirements of the bata-hydroxylase for aspartyl and asparaginyl plasma proteins.