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Spermine is a potent modulator of proton transport through LHCII

Tsiavos, Theodoros

Spermine is a potent modulator of proton transport through LHCII created by Theodoros Tsiavos, Nikolaos E. Ioannidis, Achilleas Tsortos, Electra Gizeli and Kiriakos Kotzabasis - Journal of Plant Physiology Volume 177 .

The effect of spermine on proton transport across large unilamellar liposomes containing incorporated complexes of the PSII antenna has been studied with the application of a pH-sensitive dye entrapped inside the vesicles. Both monomeric LHCbs and trimeric LHCII increased the permeability of proteoliposomes to protons when in a partly aggregated state within the lipid membrane. We have previously shown that a spermine-induced conformational change in LHCII results in its aggregation and ultimately in the enhancement of excitation energy as heat (qE). In this paper, spermine-induced aggregation of LHCII was found to facilitate proton transport across the proteoliposomes, indicating that a second protective mechanism (other than qE) might exist and might be regulated in vivo by polyamines when photosynthesis is saturated in excess light.

0176-1617


Aggregation
Light harvesting complex II
Liposomes

QK711.2 JOU