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OXIDASE REACTION OF VARIOUS GROUPS OF BACTERIA
1Laboratories of The Rockefeller Institute for Medical Research.
The Journal of Experimental Medicine
|October 30, 2009
Summary
This study introduces a new method for detecting bacterial oxidase activity using p-aminoleucomalachite green. Pneumococci and certain streptococci strains show significant oxidase activity, with optimal conditions identified for bacterial oxidase detection.
Area of Science:
- Microbiology
- Biochemistry
Background:
- Bacterial oxidase activity is crucial for microbial metabolism and identification.
- Existing methods for detecting oxidase activity can be complex or lack sensitivity.
Purpose of the Study:
- To develop a simple and effective technique for studying bacterial oxidase action.
- To investigate the oxidase activity of pneumococci and other bacterial species using a novel substrate.
Main Methods:
- A simple oxidation reaction using p-aminoleucomalachite green as a substrate.
- Culturing bacterial species, including pneumococci and streptococci, on various media, including animal sera and broths.
- Assessing oxidase activity based on the degree of p-aminoleucomalachite green oxidation.
Main Results:
- Pneumococci exhibit oxidase activity when grown on animal sera under aerobic conditions, with varying suitability across different animal sera.
- Optimal conditions for pneumococcal oxidase production include slight hemoglobin, dextrose, acidic pH, and heated fresh serum.
- Among 23 species tested, only pneumococci, Streptococcus viridans, and Streptococcus haemolyticus showed significant oxidase activity.
- Hemolytic streptococci from human and bovine sources displayed similar oxidase activity, with strains from milk/cheese showing the least.
Conclusions:
- The p-aminoleucomalachite green oxidation assay is a simple and effective method for detecting bacterial oxidase activity.
- Pneumococci and specific streptococci strains possess notable oxidase activity, differentiating them from other tested bacteria.
- The study provides insights into the optimal conditions for bacterial oxidase production and detection, aiding in microbial identification and characterization.
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