title: Cloning and characterization of a hemolysin gene from Actinobacillus (Haemophilus) pleuropneumoniae.
abstract: Neutralizing antisera to the leukotoxin secreted by Pasteurella haemolytica neutralized the hemolysin of Actinobacillus pleuropneumoniae and recognized a 110-kD antigen in cell-free culture supernatants from this organism. A series of nine overlapping recombinant phage clones carrying the gene for this 110-kD antigen were identified using affinity-purified anti-hemolysin antibody and a DNA probe containing sequences from the P. haemolytica lktCA genes. Eight of the nine clones expressed a 110-kD protein recognized by both anti-leukotoxin and anti-hemolysin antisera. The remaining clone expressed a truncated 80-kD antigen which was also recognized by both antisera. Sequence analysis of a region of the cloned DNA revealed two open reading frames encoding proteins with predicted masses of 18.5 and 102.5 kD. These genes, which we designate appC and appA, respectively, are similar in sequence to the hlyCA genes of Escherichia coli and the lktCA genes of P. haemolytica. Hemolytic activity could be detected in lysates of E. coli harboring plasmids containing the appCa genes.
authors.affiliation: Department of Biochemistry and Biophysics, College of Agriculture and Life Sciences, Texas A&M University, College Station 77843.
authors.forename: Y F
authors.initials: YF
authors.lastname: Chang
authors.forename: R
authors.initials: R
authors.lastname: Young
authors.forename: D K
authors.initials: DK
authors.lastname: Struck
mesh_terms: D000188:Actinobacillus / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D006459:Hemolysin Factors / Q000235:genetics; D006460:Hemolysin Proteins / Q000235:genetics*; D006461:Hemolysis / Q000235:genetics; D008969:Molecular Sequence Data; D010325:Pasteurella / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D014170:Transformation, Genetic
chemical_list: D006460:Hemolysin Proteins