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[Physiological properties of enterococci after long-term storage].
Mikrobiolohichnyi Zhurnal (Kiev, Ukraine : 1993)
|January 15, 2009
Summary
Long-term storage of enterococcal strains caused discrepancies in physiological property testing. Lyophilized enterococci showed altered fermentation results for key carbohydrates like glycerol and sucrose.
Area of Science:
- Microbiology
- Bacteriology
- Molecular Biology
Context:
- Enterococcal strains were isolated from the gastrointestinal tract of long-livers between 1978-1981.
- These strains underwent long-term storage in a lyophilized state.
Purpose:
- To investigate discrepancies in physiological properties of enterococcal strains after long-term lyophilized storage.
- To compare the accuracy of conventional tube tests and API-systems for assessing enterococcal carbohydrate fermentation.
Summary:
- Significant discrepancies were observed in physiological properties, particularly carbohydrate fermentation, of enterococcal strains after long-term lyophilized storage.
- Conventional tube tests yielded different results post-storage for glycerol, sucrose, mannitol, sorbitol, and raffinose fermentation.
- API-systems also showed discrepancies when compared to conventional tube tests, most notably in glycerol, mannitol, and sorbitol fermentation.
Impact:
- Highlights the instability of certain enterococcal physiological properties over time, impacting accurate identification.
- Underscores the need for careful validation of microbial identification methods, especially for long-term stored cultures.
- Suggests potential challenges in using historical microbial strain data for current research without re-evaluation.
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