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Updated: Jul 5, 2026
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Isolation, Propagation, and Identification of Bacterial Species with Hydrocarbon Metabolizing Properties from Aquatic Habitats
Published on: December 7, 2021
Characterization of Lactococcus lactis subsp. lactis isolated from surface waters
1Czech Collection of Microorganisms, Department of Experimental Biology, Faculty of Science, Masaryk University, 602 00, Brno, Czechia. mpavel@sci.muni.cz
Folia Microbiologica
|May 16, 2008
Summary
Nine Lactococcus lactis subsp. lactis strains were misidentified as enterococci in surface water samples. These bacteria can mimic enterococci on selective media and in biochemical tests, highlighting the need for accurate identification methods.
Area of Science:
- Microbiology
- Environmental Science
- Food Safety
Background:
- Enterococci are common indicators of fecal contamination in surface waters.
- Selective media and biochemical tests are typically used for enterococcal identification.
- Misidentification of bacteria can lead to inaccurate environmental assessments.
Purpose of the Study:
- To identify presumptive enterococci isolated from surface waters.
- To investigate the occurrence and identification characteristics of Lactococcus lactis subsp. lactis in aquatic environments.
- To evaluate molecular methods for differentiating Lactococcus lactis subsp. lactis from Enterococcus species.
Main Methods:
- Isolation of presumptive enterococci on Slanetz-Bartley and/or kanamycin-esculin-azide agar.
- Repetitive sequence-based PCR (rep-PCR) fingerprinting using the (GTG)5 primer.
- Biotyping and automated ribotyping with EcoRI (RiboPrinter microbial characterization system).
Main Results:
- Nine isolated strains were identified as Lactococcus lactis subsp. lactis, not Enterococcus species.
- Lactococcus lactis subsp. lactis strains exhibited characteristics that mimicked enterococci on selective media and in biochemical tests.
- (GTG)5 rep-PCR fingerprinting reliably identified these strains and differentiated them from enterococci.
Conclusions:
- Lactococcus lactis subsp. lactis can be found in surface waters and may be misidentified as enterococci.
- Accurate identification requires methods beyond standard selective media and biochemical tests.
- (GTG)5 rep-PCR is a rapid and reliable method for identifying Lactococcus lactis subsp. lactis, while ribotyping aids in intrasubspecies analysis.
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