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IS LIVING PROTOPLASM PERMEABLE TO IONS?
1Laboratory of Plant Physiology, Cambridge, and The Rockefeller Institute for Medical Research.
The Journal of General Physiology
|October 30, 2009
Summary
Hydrogen sulfide (H2S) primarily enters the Valonia macrophysa cell sap as undissociated molecules under normal conditions. This suggests a specific transport mechanism for H2S entry into plant cells.
Area of Science:
- Plant Physiology
- Biochemistry
- Cell Biology
Background:
- Hydrogen sulfide (H2S) is a signaling molecule in plants.
- Understanding H2S transport across cell membranes is crucial for elucidating its physiological roles.
- Valonia macrophysa, a large marine alga, provides a model system for studying cellular transport.
Purpose of the Study:
- To investigate the mechanism of hydrogen sulfide (H2S) entry into the cell sap of Valonia macrophysa.
- To determine the form in which H2S crosses the cell membrane.
Main Methods:
- Experiments were conducted under normal physiological conditions.
- The study focused on the cellular uptake of H2S in Valonia macrophysa.
Main Results:
- Little to no H2S was observed to enter the cell sap of Valonia macrophysa.
- The primary form of H2S entry, when it occurred, was as undissociated molecules.
Conclusions:
- The cell membrane of Valonia macrophysa exhibits limited permeability to dissociated forms of H2S.
- H2S transport into this algal cell is likely mediated by undissociated H2S molecules, implying specific membrane interactions or transport pathways.
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