"Eesti Teadusfondi uurimistoetus" projekt ETF9453
ETF9453 "Energiatasemete struktuur ja valkude dünaamika looduslikes valgustkoguvates kompleksides (1.01.2012−31.12.2015)", Jörg Pieper, Tartu Ülikool, Loodus- ja tehnoloogiateaduskond, Tartu Ülikooli Füüsika Instituut.
ETF9453
Energiatasemete struktuur ja valkude dünaamika looduslikes valgustkoguvates kompleksides
Energy level structure and protein dynamics in a natural light-harvesting complex
1.01.2012
31.12.2015
Eesti Teadusfondi uurimistoetus
ValdkondAlamvaldkondCERCS erialaFrascati Manual’i erialaProtsent
4. Loodusteadused ja tehnika4.10. FüüsikaP180 Metroloogia, instrumentatsioon1.2. Füüsikateadused (astronoomia ja kosmoseteadus, füüsika ja teised seotud teadused)100,0
PerioodSumma
01.01.2012−31.12.20129 912,00 EUR
01.01.2013−31.12.20139 912,00 EUR
01.01.2014−31.12.20149 912,00 EUR
01.01.2015−31.12.20159 912,00 EUR
39 648,00 EUR

Valkude dünaamikat ja pigmendi-proteiini vastasmõju fotosünteetilistes kompleksides kavandatakse uurida uuenduslikul meetodil, kombineerides selektiivset optilist spektroskoopiat ja kvaasi- ning mitteelastset neutronhajumist. Energiatasemete struktuuri ja eksiton-foonon vastasmõju ettevalmistatud antennivalkudes uuritakse madalatel temperatuuridel, kasutades hästi tuntud spektraalsälkamise ja fluorestsentsi meetodeid. Kvaasi- ja mitteelastse neutronhajumise lisamine optilisele spektroskoopiale annab palju detailsema ja kvantitatiivsema arusaamise valkude vibroonsest ja konformatsioonilisest dünaamikast kõrgematel, ka füsioloogilistel temperatuuridel. Lisaks elektron-interaktsioonide käsitlemisele on kavandatavatel uuringutel potentsiaal selgitada välja, kuidas valguline keskkond kohandab pigmentide spektroskoopilisi omadusi efektiivse valguse kogumise, energia ülekande ja valguskindluse suunas. Peale selle, oodatavad tulemused võimaldaksid sügavamalt aru saada antennide funktsionaalsusest kõrgematel, sealhulgas füsioloogilistel temperatuuridel.
Proteins can be considered as molecular (nano-)machines, whose structures are designed to efficiently perform their biological function. In photosynthesis, antenna protein complexes serve in efficient harvesting of solar energy and ultrafast excitation energy transfer. However, despite of the availability of high-resolution X-ray structures and remarkable advances in theoretical simulations, our insight into excitation energy transfer processes is still limited due to the complexity of native antennae. The major antenna complex of green plants is the light-harvesting complex of Photosystem II (LHC II). In the case of LHC II it is apparent that currently different structural assignments of low-energy states are reported in the literature. In addition, the temperature dependence of excited state positions cannot be understood in terms of presently existing theoretical models. A sudden red-shift of the lowest energy state with increasing temperature above 120 K appears to indicate an influence of conformational protein dynamics on the excited state position. Therefore, the objective of this project is to combine the potentials of site-selective optical spectroscopy and quasielastic neutron scattering to directly investigate effects of conformational protein dynamics and of pigment-pigment interactions in antennae at low-, but also at elevated temperatures. In addition, the use of advanced sample preparations is necessary to circumvent the inherent heterogeneity of LHC II with the presence of several isoforms and a large number of pigment molecules. Therefore, hole-burning and site-selection experiments will be carried out for LHC II samples of different complexity: a) individual isoforms, b) mutants lacking certain pigments, and c) LHC II embedded into lipid bilayers. The focus in mutant studies is on complexes lacking those pigments proposed to carry the lowest energy state. In parallel, effects of pigment-pigment and pigment-protein interaction will be studied in simple model systems containing only one or two pigment molecules. These studies will lead to a detailed characterization of the electronic energy level structure and electron-phonon coupling in model systems and in LHC II at low temperature, where advanced theoretical models are available. Furthermore, quasielastic neutron scattering experiments provide access to the vibrational density of states and to conformational protein dynamics at higher and even physiological temperatures.

Vastutav täitja (1)

IsikKraadTöökoht ja ametCVOsalemise periood
Jörg PieperdoktorikraadTartu Ülikool, Loodus- ja tehnoloogiateaduskond, Tartu Ülikooli Füüsika Instituut, bioloogilise füüsika professor (1,00)EST / ENG01.01.2012−31.12.2015

Põhitäitjad (5)

IsikKraadTöökoht ja ametCVOsalemise periood
Petrica ArteneTöökoht puudubEST / ENG01.01.2014−30.06.2014
Arvi FreibergdoktorikraadEST / ENG01.01.2012−31.12.2015
Maksym GolubdoktorikraadTartu Ülikool, Loodus- ja tehnoloogiateaduskond, Tartu Ülikooli Füüsika Instituut, biofüüsika nooremteadur (1,00)EST / ENG01.01.2015−31.08.2015
Galyna GryliukTöökoht puudubEST / ENG01.02.2013−30.06.2013
Kamarniso IsmailovaTöökoht puudub01.02.2012−30.06.2013
Publikatsioonid
Publikatsioonid
Nagy, Gergely; Pieper, Jörg; Krumova, Sashka; Kovács, Laszlo; Trapp, Marcus; Garab, Gyözö; Peters, Judith (2012). Dynamic properties of photosystem II membranes at physiological temperatures characterized by elastic incoherent neutron scattering. Increased flexibility associated with the inactivation of the oxygen evolving complex. Photosynthesis Research, 111, 113−124.10.1007/s11120-011-9701-x.
Pieper, Jörg; Trapp, Marcus; Skomorokhov, Andrei; Natkaniec, Ireneusz; Peters, Judith; Renger, Gernot (2012). Temperature-dependent vibrational and conformational dynamics of photosystem II membrane fragments from spinach investigated by elastic and inelastic neutron scattering. Biochimica et Biophysica Acta-Bioenergetics, 1817 (8), 1213−1219.10.1016/j.bbabio.2012.03.020.
Feng, Ximao; Kell, Adam; Pieper, Jörg; Jankowiak, Ryszard (2013). Modeling of Optical Spectra of the Light-Harvesting CP29 Antenna Complex of Photosystem II-Part II. The Journal of Physical Chemistry B, 117 (22), 6593−6602.10.1021/jp4004278.
Gryliuk, G.; Rätsep, M.; Hildebrandt, S.; Irrgang, K.-D.; Eckert, H.-J.; Pieper, Jörg (2014). Excitation energy transfer and electron-vibrational coupling in phycobiliproteins of the cyanobacterium Acaryochloris marina investigated by site-selective spectroscopy. Biochimica et Biophysica Acta-Bioenergetics, 1837 (9), 1490−1499.10.1016/j.bbabio.2014.02.010.
Feng, Ximao; Pan, Xiaowei; Li, Mei; Pieper, Jörg; Chang, Wenrui; Jankowiak, Ryszard (2013). Spectroscopic Study of the Light-Harvesting CP29 Antenna Complex of Photosystem II-Part I. The Journal of Physical Chemistry B, 117 (22), 6585−6592.10.1021/jp4004328.
Rusevich, L.; Garcia Sakai, V.; Franzetti, B.; Johnson, M.; Natali, F.; Pellegrini, E.; Peters, J.; Pieper, J.; Weik, M.; Zaccai, G. (2013). Perspectives in biological physics: The nDDB project for a neutron Dynamics Data Bank for biological macromolecules. European Physical Journal E, 36 (7), 80.10.1140/epje/i2013-13080-5.
Golub, Maksym; Irrgang, Klaus-Dieter; Rusevich, Leonid; Pieper, Jörg (2015). Vibrational Dynamics of Plant Light-Harvesting Complex LHC II Investigated by Quasi- and Inelastic Neutron Scattering. 83. 02004.10.1051/epjconf/20158302004.
Pieper, Jörg (2015). The Functional Role of Protein Dynamics in Photosynthetic Reaction Centers Investigated by Elastic and Quasielastic Neutron Scattering. EPJ Web of Conferences, 83, 02013.10.1051/epjconf/20158302013.
Rusevich, Leonid; Embs, Jan; Bektas, Inga; Paulsen, Harald; Renger, Gernot; Pieper, Jörg (2015). Protein and solvent dynamics of the water-soluble chlorophyll-binding protein (WSCP). EPJ Web of Conferences, 83, 02016.10.1051/epjconf/20158302016.
Vrandecic, Kamarniso; Rätsep, Margus; Wilk, Laura; Rusevich, Leonid; Golub, Maksym; Reppert, Mike; Irrgang, Klaus; Kühlbrandt, Werner; Pieper, Jörg (2015). Protein Dynamics Tunes Excited State Positions in Light-Harvesting Complex II. The Journal of Physical Chemistry B, 119 (10), 3920−3930.10.1021/jp5112873.
Pieper, Jörg; Freiberg, Arvi (2014). Electron-phonon and exciton-phonon coupling in light harvesting. Insights from line-narrowing spectroscopies. In: Golbeck, John; van der Est, Art (Ed.). The Biophysics of Photosynthesis (45−78).. Springer.10.1007/978-1-4939-1148-6.
Pieper, Jörg (2015). Protein Dynamics Tunes Excited State Positions in Light-Harvesting Complex II. The Journal of Physical Chemistry B, x−x.10.1021/jp5112873.
Pieper, Jörg (2015). Protein and solvent dynamics of the water-soluble chlorophyll-binding protein (WSCP). EPJ Web of Conferences, 83, 02016.10.1051/epjconf/20158302016.
Pieper, Jörg (2015). Vibrational Dynamics of Plant Light-Harvesting Complex LHC II Investigated by Quasi- and Inelastic Neutron Scattering. 83. 02004.10.1051/epjconf/20158302004.