Genetic approach to the construction of a controllable phage display platform for use in optimized therapeutic development

Abstract

Bacteriophage Lambda (λ) has played an historical role as an essential tool in our current understanding of molecular genetics. It’s major capsid protein gpD occurs on each capid at 405 to 420 copies per phage in homotrimeric form and functions to stabilize the head and likely to compact the genomic DNA. Th e interesting conformation of this protein allows for its exploitation through the genetic fusion of peptides or proteins to either the amino or carboxy terminal end, while retaining phage assembly and viability. We endeavoured to design and construct a highly controllable head decoration system governed by two genetic conditional regulation systems; temperature sensitive repressor expression and bacterial conditional amber mutation suppression. We have sequenced an historical amber mutant of D identifying the position of the stop codon, and employing this mutant in combination with our cellular and plasmid constructs, we will endeavour to measure the decoration of the capsid by a D::gfp fusion under varying conditions. Th is controllable system has the ability to establish a variable number of fusions per phage based on genetic and physical environment without compromising viability.This approach has important implications in the design of new therapeutics in which steric hindrance and avidity are important concerns. To this end we have applied this process innovation and are in the process of testing, toward the development and optimization of new Alzheimer’s Disease therapeutic vaccines, S. aureus, M. tuberculosis and P. acnes antibacterials.