Abstract
The following studies describe the construction of a plasmid vector, using E. coli as a host, designed to shuttle a carotenoid biosynthesis gene cluster between E. coli and L. casei, and evaluate the structural stability of the plasmid and carotenoid biosynthesis after shuttling. A Lactobacillus replicon and an erythromycin resistance marker was prepared from plasmid pLP503, a shuttle vector for Lactobacillus and E coli. This insert was ligated into linearized PCAR 1 6, a plasmid vector which contains a portion of the carotenoid biosynthesis pathway isolated from Erwinia uredovora, and expresses 0-carotene synthesis in E. coli. The recombinant shuttle vector (PCSVKI) resulting from this ligation was transformed into E. coli resulting in orange colonies; acquisition was analyzed and verified by agarose gel electrophoresis. Plasmid PCSVK I was then electroporated into L. casei and acquisition was analyzed and verified by gel electrophoresis. Plasmid PCSVKI prepared from L. casei was retransformed into E coli, again resulting in orange colonies due to synthesis of 0-carotene. Results indicate that plasmid PCSVKI maintains its structural stability and its ability to express 0-carotene synthesis in E. coli while functioning as a shuttle vector between E coli and L. casei.
White, Kevin E (1996). Development of a carotenoid shuttle vector for Lactobacillus. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1996 -THESIS -W534.