Related Experiment Videos
beta-Lactamase production by intestinal spirochaetes.
D S Tompkins1, M R Millar, J Heritage
1Department of Microbiology, University of Leeds, UK.
Journal of General Microbiology
|March 1, 1987
Summary
Four of nineteen human intestinal spirochaete strains produced beta-lactamase, an enzyme active against penicillins. This non-inducible, membrane-bound enzyme was not transferable and not plasmid-mediated.
Area of Science:
- Microbiology
- Bacterial genetics
Background:
- Intestinal spirochaetes are a group of bacteria inhabiting the human gut.
- Beta-lactamase enzymes confer resistance to beta-lactam antibiotics, including penicillins.
- Understanding antibiotic resistance mechanisms in gut bacteria is crucial for public health.
Purpose of the Study:
- To investigate the prevalence and characteristics of beta-lactamase production in human intestinal spirochaetes.
- To determine the nature of the beta-lactamase enzyme and its genetic basis.
Main Methods:
- Isolation and identification of intestinal spirochaete strains from human subjects.
- Detection and characterization of beta-lactamase activity.
- Enzyme inhibition assays using clavulanic acid.
- Subcellular localization studies (membrane-bound).
- Plasmid analysis and investigation of transferability.
Main Results:
- Beta-lactamase production was detected in 4 out of 19 human intestinal spirochaete isolates.
- The enzyme exhibited preferential activity against penicillins and was inhibited by clavulanic acid.
- The beta-lactamase was found to be membrane-bound and non-inducible.
- No plasmids were detected in the beta-lactamase-producing strains.
- The beta-lactamase production trait was not transferable to non-producing strains.
Conclusions:
- A subset of human intestinal spirochaetes possesses intrinsic beta-lactamase activity.
- The beta-lactamase is a chromosomally encoded, membrane-associated enzyme.
- The absence of plasmids suggests a non-transferable mechanism of resistance in these isolates.