Modeling of variant copies of subunit D1 in the structure of photosystem II from Thermosynechococcus elongatus.

@article{citeulike:2677195, abstract = {Abstract In the cyanobacterium Thermosynechococcus elongatus BP-1, living in hot springs, the light environment directly regulates expression of genes that encode key components of the photosynthetic multi-subunit protein-pigment complex photosystem II (PSII). Light is not only essential as energy source to power photosynthesis, but leads to formation of aggressive radicals which induce severe damage of protein subunits and organic cofactors. Photosynthetic organisms developed several protection mechanisms against this photo-damage, one being the differential expression of genes coding for the reaction center subunit D1 in PSII. Testing the expression of the three different genes (psbAI, psbAII, psbAIII) coding for D1 in T. elongatus under culture conditions used for preparing the material used in crystallization of PSII showed that under these conditions only subunit PsbA1 is present. However, exposure to high-light intensity induced partial replacement of PsbA1 with PsbA3. Modeling of the variant amino acids of the three different D1 copies in the 3.0 A resolution crystal structure of PSII revealed that most of them are in direct vicinity to redox-active cofactors of the electron transfer chain. Possible structural and mechanistic consequences for electron transfer are discussed.}, author = {Loll, Bernhard and Broser, Matthias and K\'{o}s, Peter B B. and Kern, Jan and Biesiadka, Jacek and Vass, Imre and Saenger, Wolfram and Zouni, Athina }, citeulike-article-id = {2677195}, doi = {10.1515/BC.2008.058}, issn = {1431-6730}, journal = {Biological chemistry}, keywords = {psba, psii}, month = {March}, posted-at = {2008-04-16 10:39:59}, priority = {2}, title = {Modeling of variant copies of subunit D1 in the structure of photosystem II from Thermosynechococcus elongatus.}, url = {http://dx.doi.org/10.1515/BC.2008.058}, year = {2008} }

TY - JOUR ID - citeulike:2677195 L3 - citeulike-article-id:2677195 TI - Modeling of variant copies of subunit D1 in the structure of photosystem II from Thermosynechococcus elongatus. JF - Biological chemistry SN - 1431-6730 N2 - Abstract In the cyanobacterium Thermosynechococcus elongatus BP-1, living in hot springs, the light environment directly regulates expression of genes that encode key components of the photosynthetic multi-subunit protein-pigment complex photosystem II (PSII). Light is not only essential as energy source to power photosynthesis, but leads to formation of aggressive radicals which induce severe damage of protein subunits and organic cofactors. Photosynthetic organisms developed several protection mechanisms against this photo-damage, one being the differential expression of genes coding for the reaction center subunit D1 in PSII. Testing the expression of the three different genes (psbAI, psbAII, psbAIII) coding for D1 in T. elongatus under culture conditions used for preparing the material used in crystallization of PSII showed that under these conditions only subunit PsbA1 is present. However, exposure to high-light intensity induced partial replacement of PsbA1 with PsbA3. Modeling of the variant amino acids of the three different D1 copies in the 3.0 A resolution crystal structure of PSII revealed that most of them are in direct vicinity to redox-active cofactors of the electron transfer chain. Possible structural and mechanistic consequences for electron transfer are discussed. KW - psba KW - psii AU - Loll, Bernhard AU - Broser, Matthias AU - Kós, Peter B AU - Kern, Jan AU - Biesiadka, Jacek AU - Vass, Imre AU - Saenger, Wolfram AU - Zouni, Athina PY - 2008/03/06/ UR - http://dx.doi.org/10.1515/BC.2008.058 ER -