Open AccessExpression of β‐lactamase in Coxiella burnetii transformants
Author(s) -
Suhan Michelle L,
Thompson Herbert A
Publication year - 2000
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.1574-6968.2000.tb09031.x
Subject(s) - coxiella burnetii , plasmid , amp resistance , ampicillin , biology , beta lactamase , microbiology and biotechnology , electroporation , gene , escherichia coli , genetics , antibiotics
Coxiella burnetii can be transformed to ampicillin resistance by electroporation with plasmids encoding β‐lactamase. However, non‐plasmid emergence of resistance to ampicillin also develops. To validate the usefulness of the bla gene marker for selection and detection, transformed C. burnetii were examined for β‐lactamase expression by use of immunoblotting after SDS‐PAGE. The 29‐kDa mature form of the β‐lactamase protein was detected in C. burnetii lysates. Quantitation of these immunoblot signals showed that C. burnetii surprisingly expressed low levels of β‐lactamase. The results validate the use of plasmid‐encoded ampicillin resistance as a means for selecting C. burnetii transformants; they also suggest that levels of ampicillin used for selection pressure should be empirically determined and that detection of β‐lactamase by antibody blotting done to confirm transformants.