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04:41
Measuring Lactase Enzymatic Activity in the Teaching Lab
Published on: August 6, 2018
STUDIES ON BACTERIAL ENZYMES : VII. LACTASE AND LIPASE OF THE COLON BACILLUS
L Lowenstein1, W L Fleming, J M Neill
1Department of Bacteriology and Immunology, Vanderbilt University Medical School, Nashville.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Colon bacilli contain heat-labile enzymes, lactase and lipase, that function outside the cell. This study shows lactase activity is the initial step in lactose fermentation by these bacteria.
Area of Science:
- Microbiology
- Enzymology
Background:
- Colon bacilli are microorganisms known to inhabit the digestive tract.
- Enzymatic activity within bacteria plays a crucial role in metabolic processes.
Purpose of the Study:
- To investigate the enzymatic activity of colon bacilli, specifically lactase and lipase.
- To determine the role of these enzymes in lactose fermentation.
Main Methods:
- Physical disintegration of colon bacilli to isolate intracellular substances.
- Preparation of sterile filtered solutions containing these substances.
- Demonstration of lactase activity and detection of hexose products.
Main Results:
- Endocellular heat-labile lactase and lipase enzymes were found to be active in isolated solutions.
- The action of lactase was demonstrated, with hexose products detected.
- Experimental evidence confirmed lactose hydrolysis as the initial step in fermentation.
Conclusions:
- Colon bacilli possess functional intracellular lactase and lipase enzymes.
- Lactose hydrolysis by lactase is the primary and initial step in lactose fermentation by colon bacilli.
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