title: Cloning and expression of a species-specific early immunogenic 36-kilodalton protein of Mycoplasma hyopneumoniae in Escherichia coli.
abstract: Mycoplasma hyopneumoniae, the etiologic agent of porcine enzootic pneumonia, synthesizes a 36-kDa protein which is an early and strong immunogenic factor in experimentally and naturally infected swine. The gene encoding this protein was cloned by screening a gene library of M. hyopneumoniae DNA with rabbit hyperimmune serum made against whole M. hyopneumoniae cells and convalescent-phase swine serum. Analysis of the recombinant protein expressed in Escherichia coli by immunoblot techniques showed that the protein is expressed in E. coli in its full length and does not cross-react with proteins from M. flocculare or M. hyorhinis. Genetic analysis showed that the gene was expressed from the lac promoter of the vector and seems to be translationally initiated from its own ribosome binding site. Subcloning in a transcriptional fusion vector to optimize expression resulted in production of the 36-kDa protein in E. coli at levels up to 30% of total protein.
authors.affiliation: Institute for Veterinary Bacteriology, University of Berne, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Strasser
authors.forename: J
authors.initials: J
authors.lastname: Frey
authors.forename: G
authors.initials: G
authors.lastname: Bestetti
authors.forename: M
authors.initials: M
authors.lastname: Kobisch
authors.forename: J
authors.initials: J
authors.lastname: Nicolet
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000032:analysis / Q000235:genetics* / Q000276:immunology; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics*; D005798:Genes, Bacterial; D009174:Mycoplasma / Q000032:analysis / Q000235:genetics*; D011401:Promoter Regions, Genetic; D011817:Rabbits; D013045:Species Specificity; D013552:Swine
chemical_list: D001426:Bacterial Proteins