Open AccessThe CAMP effect of Actinobacillus pleuropneumoniae is caused by Apx toxins
Author(s) -
Jansen Ruud,
Briaire Jan,
Kamp Elbarte M.,
Gielkens Arno L.J.,
Smits Mari A.
Publication year - 1995
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1995.tb07407.x
Subject(s) - actinobacillus pleuropneumoniae , microbiology and biotechnology , biology , toxin , escherichia coli , actinobacillus , bacteria , gene , biochemistry , serotype , genetics
Actinobacillus pleuropneumoniae shows synergistic haemolysis when cocultured with Staphylococcus aureus on blood agar plates. This CAMP effect has been attributed to a discrete CAMP factor, but also to the A. pleuropneumoniae ‐RTX‐toxins I, II, and III. We examined the CAMP effect of recombinant Escherichia coli strains that secreted each of these toxins, and of A. pleuropneumoniae mutant strains that were devoid of one or more these toxins. We found that the E. coli strains were CAMP positive, whereas the A. pleuropneumoniae strain devoid of functional toxin genes was CAMP negative. This demonstrated that the CAMP effect of A. pleuropneumoniae is caused by the toxins and that no CAMP factor per se exists.