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. 1983 Mar;71(3):673–676. doi: 10.1104/pp.71.3.673

A New Mechanism for Adaptation to Changes in Light Intensity and Quality in the Red Alga Porphyra perforata1

III. Fluorescence Transients in the Presence of 3-(3,4-Dichlorophenyl)-1,1-dimethylurea

Kazuhiko Satoh 1,2,2, David C Fork 1,2
PMCID: PMC1066097  PMID: 16662886

Abstract

In the red alga Porphyra perforata, the level of chlorophyll fluorescence in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) decreased during illumination of the thallus. The results showed that: (a) this decay was related to the photooxidative activity of photosystem I; (b) Q, the primary electron acceptor of photosystem II, became oxidized during the decay of the fluorescence; (c) reagents which inhibit the back reaction of photosystem II inhibited the decay.

From these results, it is suggested that, when conditions in the chloroplasts of this red alga become too oxidative, excess light energy can be converted to heat as a result of an accelerated back reaction of photosystem II. This may be one of the mechanisms by which this alga can cope with the high salt and high light conditions that can occur in its natural habitat.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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