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Updated: Aug 7, 2026
10:22
Reconstitution of a Kv Channel into Lipid Membranes for Structural and Functional Studies
Published on: July 13, 2013
Summary
Enzymatic action, like trypsin
Area of Science:
- Biochemistry
- Enzymology
- Surface Chemistry
Background:
- Enzymatic reactions often require direct contact between enzyme and substrate.
- Previous hypotheses on enzyme action across membranes have been debated.
- Understanding enzyme-substrate interactions is crucial in biological and chemical processes.
Purpose of the Study:
- To investigate whether trypsin can exhibit enzymatic activity without crossing a membrane.
- To re-evaluate the mechanism of enzyme action at a distance.
- To explore the potential for immobilizing biomolecules across membranes.
Main Methods:
- Adsorbing bovine serum albumin (BSA) onto a nickel-plated slide.
- Protecting the BSA layer with a 120 Å thick Formvar membrane.
- Treating the system with a dilute trypsin solution and observing the reaction.
Main Results:
- Tryptic action was observed on the BSA layer.
- Experimental evidence confirmed that trypsin molecules did not penetrate the Formvar membrane.
- This supports the hypothesis of enzyme action without direct contact.
Conclusions:
- Enzymes can exert catalytic effects across semi-permeable membranes.
- The 'forced diffusion' hypothesis is supported, suggesting enzymes can act at a distance.
- This principle may be applicable to immobilizing other biomolecules, such as antibodies and antigens, across membranes.
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