The modification of proteins with fatty acids is a prevalent theme among retro-viral proteins and eukaryotic proteins involved in signal transduction. N-myristoylation of the gag polyprotein is required by many retro-viruses for proliferation, and a number of retro-viral oncoproteins require fatty acid modifications transform cells. Thus, the ability to regulate protein fatty acid acylation would be a valuable tool in the study of signal transduction and the life cycle of retro-viruses. We intend to apply catalytic antibody technology to the post-translational acylation of proteins. Immunization of mice with a single small phosphono-peptido- hapten should result in the generation of actyltransferases specific to a desired peptide sequence predetermined by the hapen. Such abzymes could be used to block natural fatty acylation effectively interrupting signal transduction or interfering with the life-cycle of retro-viruses. Our first goal in this area will be to determine if abzymes elicited against a single tripeptido-phosphonamidate can distinguish the haptenic sequence from other tripeptides in a kinetically useful manner. These experiments will be done using a combinatorial solid phase library of tripeptides, in conjunction with a novel library screening strategy. Once sufficiently selective catalysis have been generated and isolated, we will initiate experiments aimed at acylating the N-terminus of the non-myristoylated form of the MARCKS. These experiments constitute the initial work in a broader project the ultimate goal of which is to apply catalytic antibody technology to the site specific post-translational modification of proteins.