The thermostability of photosystem II photochemistry is related to maintenance of thylakoid membranes organization

0456342 - ÚVGZ 2016 RIV CZ eng C - Konferenční příspěvek (zahraniční konf.)
Karlický, Václav - Kurasová, I. - Špunda, Vladimír
The thermostability of photosystem II photochemistry is related to maintenance of thylakoid membranes organization.
Global Change: A Complex Challenge : Conference Proceedings. Brno: Global Change Research Centre, The Czech Academy of Sciences, v. v. i., 2015 - (Urban, O.; Šprtová, M.; Klem, K.), s. 142-145. ISBN 978-80-87902-10-3.
[Global Change: A Complex Challenge /4th/. Brno (CZ), 23.03.2015-24.03.2015]
Grant CEP: GA MŠMT(CZ) LO1415; GA MŠMT(CZ) ED1.1.00/02.0073; GA ČR GA13-28093S
Institucionální podpora: RVO:67179843
Klíčová slova: membrane * photosystem * photochemistry
Kód oboru RIV: EH - Ekologie - společenstva

For higher plant photosynthetic reactions, responses to the temperature changes are important, particularly if we consider global warming and the increasing frequency of extreme temperature fluctuations. High temperature stress decreases photosynthetic assimilation through the inactivation of photosystem II (PSII), the most heat-sensitive component of the oxygen-evolving complex. We have recently found higher thermostability of spruce PSII photochemistry compared to such control plants as Arabidopsis species and barley. In this work, we have therefore attempted to describe the causes of this effect on the level of the organization of pigment–protein complexes (PPCs) in spruce thylakoid membranes using circular dichroism (CD) spectroscopy. We have confirmed higher maximum efficiency of PSII photochemistry (FV/FM) for spruce needles in comparison to barley leaves. Temperature-dependent CD spectra have also demonstrated higher (by about 6°C) PSII thermostability of chiral macro-organization of PPCs in spruce thylakoid membranes compared to those in barley. However, thermal disruption of PPCs did not reveal significant differences. Our results demonstrate that the stability of PSII macro-organization in different plant species correlates with the thermostability of PSII photochemistry in intact needles/leaves and so effective PSII photochemistry is related to the maintenance of PSII macro-organization under high temperature stress.
Trvalý link: http://hdl.handle.net/11104/0256900