title: Cloning and expression of the Legionella micdadei "common antigen" in Escherichia coli.
abstract: To study individual Legionella antigens, a Legionella micdadei genomic library in Escherichia coli SC181 was established. Partially Sau3A digested L. micdadei DNA fragments (15-25 kilobase pairs (kb] were cloned into the tetracycline resistance gene of the cosmid vector pHC79. Four thousand ampicillin resistant recombinants were obtained; seven hundred were screened for expression of Legionella antigens in Western blot analysis with a polyspecific E. coli-absorbed anti-L. micdadei rabbit antibody. One of the positive clones expressed a 60 kilodalton (K) antigen, which reacted strongly with a monospecific rabbit antiserum raised against L. micdadei "common antigen" (CA), and an additional 13 K L. micdadei protein. The region encoding these two proteins from the 17 kb recombinant plasmid (pBA 2) was subcloned in pBGS18+. The DNA sequence of the CA encoding region in the 2.7 kb subcloned fragment will provide important information with respect to genetic vs. antigenic relatedness among Legionellae and other Gram-negative species, as well as to CA structure and possible function.
authors.affiliation: Department of Clinical Microbiology, Rigshospitalet, Statens Seruminstitut, Copenhagen, Denmark.
authors.forename: J M
authors.initials: JM
authors.lastname: Bangsborg
authors.forename: M T
authors.initials: MT
authors.lastname: Collins
authors.forename: N
authors.initials: N
authors.lastname: Høiby
authors.forename: P
authors.initials: P
authors.lastname: Hindersson
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology*; D001426:Bacterial Proteins / Q000235:genetics* / Q000276:immunology; D003001:Cloning, Molecular; D004926:Escherichia coli; D007123:Immunoelectrophoresis, Two-Dimensional; D007875:Legionella / Q000235:genetics* / Q000276:immunology; D008970:Molecular Weight; D015183:Restriction Mapping
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins