Dynamic changes in the proteome of Synechocystis 6803 in response to CO(2) limitation revealed by quantitative proteomics.
Cyanobacteria developed efficient carbon concentrating mechanisms which significantly improve the photosynthetic performance and survival of cells under limiting CO(2) conditions. Dynamic changes of the Synechocystis proteome to CO(2) limitation were investigated using shotgun LC-MS/MS approach with isobaric tag for relative and absolute quantification (iTRAQ) technique. Synechocystis cells grown at high (3%) CO(2) were shifted to air-level CO(2) followed by protein extraction after 6, 24, and 72 h. About 19% of the cyanobacterial proteome was identified and the expression changes were quantified for 17% of theoretical ORFs. For 76 proteins, up- or down-regulation was found to be significant (more than 1.5 or less than 0.7). Major changes were observed in proteins participating in inorganic carbon uptake, CO(2) fixation, nitrogen transport and assimilation, as well as in the protection of the photosynthetic machinery from excess of light. Further, a number of hypothetical proteins with unknown functions were discovered. In general, the cells appear to acclimate to low CO(2) without a significant stress since the stress-related molecular chaperones were down-regulated and only a minor decline was detected for proteins of phycobilisomes, photosynthetic complexes, and translation machinery. The results of iTRAQ experiment were validated by the Western blot analysis for selected proteins.
Battchikova
Natalia
N
Department of Biochemistry and Food Chemistry, Molecular Plant Biology, University of Turku, Finland. natbat@utu.fi
Vainonen
Julia P
JP
Vorontsova
Natalia
N
Keranen
Mika
M
Carmel
Dalton
D
Aro
Eva-Mari
EM
D001426:Bacterial Proteins / Q000032:analysis / Q000187:drug effects; D002244:Carbon / Q000378:metabolism; D002245:Carbon Dioxide / Q000494:pharmacology*; D000458:Cyanobacteria / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D007700:Kinetics; D020543:Proteome / Q000032:analysis* / Q000187:drug effects; D040901:Proteomics / Q000379:methods*; D046939:Synechocystis / Q000378:metabolism* / Q000502:physiology; D053719:Tandem Mass Spectrometry
D001426:Bacterial Proteins; D020543:Proteome; D002245:Carbon Dioxide; D002244:Carbon