Changes in the LHCI aggregation state during iron repletion in the unicellular red alga Rhodella violacea.
Red algae are well suited to study the effects of iron deficiency on light-harvesting complex for photosystem I (LHCI), since they are totally devoid of light-harvesting complex for photosystem II (LHCII). Iron starvation results in a reduction of the pigment content, an increase of the fluorescence yield and a new emission band at 705 nm in the 77 K fluorescence emission spectra. These changes reflect the accumulation of uncoupled, aggregated LHCI in iron-depleted cells. Reconnection of LHCI to de novo synthesized reaction center I (RCI) is the first event, which takes place after iron addition. The changes in the aggregation state of LHCI are likely to occur also in brown and green algae.
Doan
Jean Michel
JM
Organismes Photosynthétiques et Environnement, UMR 8543 CNRS, Département de Biologie, ENS 46 rue d'Ulm, 75230 cedex 05, Paris, France
Schoefs
Benoít
B
Ruban
Alexander V
AV
Etienne
Anne Lise
AL
D007501:Iron / Q000378:metabolism*; D046911:Macromolecular Substances; D010788:Photosynthesis; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry* / Q000378:metabolism*; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D000461:Rhodophyta / Q000737:chemistry* / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
D046911:Macromolecular Substances; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D007501:Iron