Expression of antigens from chromosomal and linear plasmid DNA of Borrelia coriaceae

Three recombinant plasmids containing DNA from Borrelia coriaceae, the putative agent of epizootic bovine abortion, expressed antigens in Escherichia coli that reacted with antibodies specific for B. coriaceae. Two of the recombinants each expressed a single high-molecular-weight antigen. The third recombinant expressed three smaller antigens. The DNA inserts were sized and mapped. Hybridization of the cloned inserts to pulsed-field electrophoresis samples of B. coriaceae whole-cell DNA revealed the origin of two of the inserts to be located in linear plasmids. One of these, expressing three antigens, was located in a 210-kilobase linear plasmid. A second recombinant expressed a single antigen but hybridized to at least three distinct linear plasmids. The third clone also expressed a single antigen but was demonstrated to be chromosomal in origin.