Molecular cloning and expression of Chlamydia trachomatis major outer membrane protein antigens in Escherichia coli

Abstract

DNA obtained from Chlamydia trachomatis (serovar L2) was partially digested with DNase I and inserted into the β-galactosidase gene of bacteriophage λ gt11. Seven recombinants were selected that produced immunoreactive fusion proteins which were detected with anti-C. trachomatis rabbit serum. One recombinant, designated λ gt11/L2/33, reacted with various monoclonal antibodies that recognize species-, subspecies-, and type-specific determinants on the chlamydial major outer membrane protein (MOMP). Immunoblot analysis of a λ gt11/L2/33 lysogen revealed a fusion protein that expressed a ~15,000-dalton carboxyl-terminal peptide of the chlamydial MOMP. This moiety of the MOMP possesses epitopes responsible for each of the unique reactivities demonstrated by anti-MOMP monoclonal antibodies. The λ gt11/L2/33 recombinant contained a 1.1-kilobase DNA insert which hybridized to DNA isolated from each of the 15 C. trachomatis serovars.