title: The adhesin related 30-kDa protein of Mycoplasma pneumoniae exhibits size and antigen variability.
abstract: Mycoplasma pneumoniae is a pathogenic bacterium colonizing epithelial cells of the human respirator tract. Using an erythrocyte binding assay we isolated a cytadsorption negative mutant designated M7 which has lost 12 of a total of 13 repetitive sequences of a proline rich C-terminal region of the adhesin related 30-kDa protein. The truncated adhesin related protein of 22 kDa showed reduced antigenicity compared to the corresponding wild-type protein. Moreover, the mutant M7 proved incapable of adhering to erythrocytes and to a human colon carcinoma cell line indicating that the repetitive C-terminal region of the 30-kDa protein is essential for effective cytadherence. The adhesin related 30-kDa protein as well as the truncated forms of the corresponding protein were accessible to carboxypeptidase Y which clearly shows surface exposure of the C-terminus of this protein.
authors.affiliation: Zentrum für Molekulare Biologie Heidelberg, Universität Heidelberg, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Layh-Schmitt
authors.forename: R
authors.initials: R
authors.lastname: Himmelreich
authors.forename: U
authors.initials: U
authors.lastname: Leibfried
mesh_terms: D018829:Adhesins, Bacterial / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D002268:Carboxypeptidases / Q000494:pharmacology; D043402:Cathepsin A; D015151:Immunoblotting; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009154:Mutation; D013329:Structure-Activity Relationship
chemical_list: D018829:Adhesins, Bacterial; C035471:adhesin, Mycoplasma pneumoniae; D002268:Carboxypeptidases; D043402:Cathepsin A