Hydrogen sulfide: environmental factor or signalling molecule?
Hydrogen sulfide (H₂S) has traditionally been thought of as a phytotoxin, having deleterious effects on the plant growth and survival. It is now recognized that plants have enzymes which generate H₂S, cysteine desulfhydrase, and remove it, O-acetylserine lyase. Therefore, it has been suggested that H₂S is considered as a signalling molecule, alongside small reactive compounds such as hydrogen peroxide (H₂O₂) and nitric oxide (NO). Exposure of plants to low of H₂S, for example from H₂S donors, is revealing that many physiological effects are seen. H₂S seems to have effects on stomatal apertures. Intracellular effects include increases in glutathione levels, alterations of enzyme activities and influences on NO and H₂O₂ metabolism. Work in animals has shown that H₂S may have direct effects on thiol modifications of cysteine groups, work that will no doubt inform future studies in plants. It appears therefore, that instead of thinking of H₂S as a phytotoxin, it needs to be considered as a signalling molecule that interacts with reactive oxygen species and NO metabolism, as well as having direct effects on the activity of proteins. The future may see H₂S being used to modulate plant physiology in the field or to protect crops from postharvest spoilage.
Department of Agroecology, University of J. J. Strossmayer, Osijek 31000, Croatia.
Miroslav
M
Lisjak
Tihana
T
Teklic
Ian D
ID
Wilson
Matthew
M
Whiteman
John T
JT
Hancock
D004777:Environment; D006862:Hydrogen Sulfide / Q000378:metabolism* / Q000494:pharmacology; D059828:Plant Cells / Q000187:drug effects / Q000378:metabolism; D054046:Plant Stomata / Q000187:drug effects / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects; D013312:Stress, Physiological / Q000187:drug effects
D006862:Hydrogen Sulfide
GYY4137; NaSH; hydrogen peroxide; nitric oxide