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08:42
Visual and Microscopic Evaluation of Streptomyces Developmental Mutants
Published on: September 12, 2018
THE DIFFERENTIATION OF STREPTOCOCCI BY MEANS OF FERMENTATIVE TESTS.
1Pathological Laboratory, Mt. Sinai Hospital, New York.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Streptococci exhibit varied acid production from carbohydrates. Optimal growth media are crucial for accurate chemical testing and classification of these bacteria.
Area of Science:
- Microbiology
- Bacteriology
Background:
- Previous classifications of streptococci relied on habitat and chemical tests, but lacked consistency.
- The suitability of growth media significantly impacts the observed fermentative properties of microorganisms.
Purpose of the Study:
- To investigate the fermentative properties of streptococci using optimal growth media.
- To evaluate the reliability of chemical tests for classifying streptococci.
Main Methods:
- Culturing 33 pathogenic streptococcal strains on a variety of carbohydrates (dextrose, levulose, galactose, maltose, saccharose, lactose, inulin, dextrin, mannite).
- Utilizing a specifically developed, favorable growth medium to enhance organism growth and fermentation reactions.
Main Results:
- Streptococci demonstrated considerable variation in their ability to produce acid from different carbohydrates.
- Six distinct groups of streptococci were identified based on their fermentation patterns across the tested carbohydrates.
- A significant discrepancy was noted compared to previous studies, particularly regarding inulin and lactose fermentation.
Conclusions:
- Accurate chemical testing for streptococcal classification requires the use of optimal growth media.
- The observed variability suggests that a more extensive range of carbohydrates and strains may be necessary for a definitive classification of streptococci.
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