Adaptation to high light irradiances enhances the photosynthetic Cu2+ resistance in Cu2+ tolerant and non-tolerant populations of the brown macroalgae Fucus serratus.
The relationship between light acclimation and Cu(2+) tolerance was studied in two populations of Fucus serratus known to be naturally non-tolerant and tolerant to Cu(2+). Acclimation to high irradiances increased the photosynthetic tolerance to Cu(2+). The xanthophyll cycle was apparently not involved in protecting the photosynthetic apparatus against Cu(2+) toxicity, as results showed that Cu(2+) did not induce dynamic photoinhibition. The higher photosynthetic Cu(2+) resistance of high light algae did not result in increased growth. The excess energy acquired by high light-adapted algae appeared to be utilized in Cu(2+) defense mechanisms in the Cu(2+) non-tolerant population. The polyphenol content of the algae was reciprocal to the Cu(T) content, suggesting that polyphenol may be the primary Cu(2+) defense of non-tolerant low light algae, acting through secretion and extracellular chelating of Cu(2+), while the compounds do not seem to be involved in the primary Cu(2+) tolerance mechanism in Cu(2+) tolerant algae.
Nielsen
Hanne Dalsgaard
HD
School of Life Sciences, Napier University, 10 Colinton Road, Edinburgh EH10 5DT, United Kingdom.
Nielsen
Søren Laurentius
SL
D002413:Cations, Divalent / Q000494:pharmacology / Q000633:toxicity; D002614:Chelating Agents / Q000737:chemistry / Q000494:pharmacology; D002734:Chlorophyll / Q000378:metabolism; D003300:Copper / Q000494:pharmacology* / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology; D044645:Fucus / Q000187:drug effects* / Q000254:growth & development / Q000528:radiation effects*; D008027:Light; D018384:Oxidative Stress / Q000187:drug effects / Q000528:radiation effects; D010636:Phenols / Q000737:chemistry / Q000494:pharmacology; D010788:Photosynthesis / Q000528:radiation effects*; D059808:Polyphenols; D014874:Water Pollutants, Chemical / Q000494:pharmacology* / Q000633:toxicity; D024341:Xanthophylls / Q000378:metabolism
D002413:Cations, Divalent; D002614:Chelating Agents; D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D014874:Water Pollutants, Chemical; D024341:Xanthophylls; D002734:Chlorophyll; D003300:Copper