title: Towards functional proteomics of membrane protein complexes in Synechocystis sp. PCC 6803.
abstract: The composition and dynamics of membrane protein complexes were studied in the cyanobacterium Synechocystis sp. PCC 6803 by two-dimensional blue native/SDS-PAGE followed by matrix-assisted laser-desorption ionization time of flight mass spectrometry. Approximately 20 distinct membrane protein complexes could be resolved from photoautotrophically grown wild-type cells. Besides the protein complexes involved in linear photosynthetic electron flow and ATP synthesis (photosystem [PS] I, PSII, cytochrome b6f, and ATP synthase), four distinct complexes containing type I NAD(P)H dehydrogenase (NDH-1) subunits were identified, as well as several novel, still uncharacterized protein complexes. The dynamics of the protein complexes was studied by culturing the wild type and several mutant strains under various growth modes (photoautotrophic, mixotrophic, or photoheterotrophic) or in the presence of different concentrations of CO2, iron, or salt. The most distinct modulation observed in PSs occurred in iron-depleted conditions, which induced an accumulation of CP43' protein associated with PSI trimers. The NDH-1 complexes, on the other hand, responded readily to changes in the CO2 concentration and the growth mode of the cells and represented an extremely dynamic group of membrane protein complexes. Our results give the first direct evidence, to our knowledge, that the NdhF3, NdhD3, and CupA proteins assemble together to form a small low CO2-induced protein complex and further demonstrate the presence of a fourth subunit, Sll1735, in this complex. The two bigger NDH-1 complexes contained a different set of NDH-1 polypeptides and are likely to function in respiratory and cyclic electron transfer. Pulse labeling experiments demonstrated the requirement of PSII activity for de novo synthesis of the NDH-1 complexes.
authors.affiliation: Plant Physiology and Molecular Biology, Department of Biology, University of Turku, FIN-20014 Turku, Finland.
authors.forename: Mirkka
authors.initials: M
authors.lastname: Herranen
authors.forename: Natalia
authors.initials: N
authors.lastname: Battchikova
authors.forename: Pengpeng
authors.initials: P
authors.lastname: Zhang
authors.forename: Alexander
authors.initials: A
authors.lastname: Graf
authors.forename: Sari
authors.initials: S
authors.lastname: Sirpiö
authors.forename: Virpi
authors.initials: V
authors.lastname: Paakkarinen
authors.forename: Eva-Mari
authors.initials: EM
authors.lastname: Aro
mesh_terms: D000255:Adenosine Triphosphate / Q000096:biosynthesis; D001426:Bacterial Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism; D000458:Cyanobacteria / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D004579:Electron Transport; D015180:Electrophoresis, Gel, Two-Dimensional; D005798:Genes, Bacterial; D007501:Iron / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D009252:NADPH Dehydrogenase / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D010788:Photosynthesis; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D040901:Proteomics; D012965:Sodium Chloride / Q000494:pharmacology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; D045322:Photosynthetic Reaction Center Complex Proteins; D002245:Carbon Dioxide; D012965:Sodium Chloride; D000255:Adenosine Triphosphate; D007501:Iron; D009252:NADPH Dehydrogenase