The bacteria genus, Clostridium, includes many species that are naturally capable of degrading cellulose and producing valuable chemicals and fuel alcohols. Unfortunately the genetic engineering tools for developing improved strains are limited for all clostridia. This project will develop novel approaches for enhancing chromosomal integration in all clostridia species. With an enhanced recombination system for clostridia, it would become possible to quickly knock out and knock in genes, allowing new strains with superior production capabilities to be quickly engineered. Phase I will demonstrate the feasibility of improving site-specific chromosomal integration via recombinant over-expression of native and heterologous proteins involved in homologous recombination. Phase I will focus on the over-expression of individual proteins, and Phase II will build upon those results by studying the over-expression of combinations of proteins. Commercial Applications and other Benefits as described by the awardee The technology should significantly accelerate strain development in solventogenic and other clostridia species, leading to the microbial conversion of renewable carbohydrates to chemicals and fuels. Such a development would aid our nations goals of developing sustainable and greener technologies for the production of chemicals and transportation fuels