Breaking Lac [a remedy for lactose intolerance]

Abstract

Lactose intolerance is a digestive condition associated with the inability to fully digest lactose (a sugar found in milk products), and affects ~ 5 billion people worldwide. The symptoms include bloating, stomach cramps, diarrhea and nausea. In this project, we propose to use a synthetic biology approach to achieve 2 major aims: (1) design and construct an Escherichia coli probiotic strain (Lac Breaker) to tackle the lactose intolerance problem which involves high expression of the beta-galactosidase enzyme (driven by expression vector A) and its release from the E. coli cell by autolysis (using a lysis gene cassette on vector B); and (2) evaluate different "lysis gene cassette" constructs as an effective means to extract high value-added recombinant proteins in biotechnology. This is an improvement of the iGEM project of the 2008 Caltech team (Curing Lactose Intolerance) with greater emphasis on the design, construction and evaluation of various "lysis gene cassettes".