title: Diurnal rhythms result in significant changes in the cellular protein complement in the cyanobacterium Cyanothece 51142.
abstract: Cyanothece sp. ATCC 51142 is a diazotrophic cyanobacterium notable for its ability to perform oxygenic photosynthesis and dinitrogen fixation in the same single cell. Previous transcriptional analysis revealed that the existence of these incompatible cellular processes largely depends on tightly synchronized expression programs involving ∼30% of genes in the genome. To expand upon current knowledge, we have utilized sensitive proteomic approaches to examine the impact of diurnal rhythms on the protein complement in Cyanothece 51142. We found that 250 proteins accounting for ∼5% of the predicted ORFs from the Cyanothece 51142 genome and 20% of proteins detected under alternating light/dark conditions exhibited periodic oscillations in their abundances. Our results suggest that altered enzyme activities at different phases during the diurnal cycle can be attributed to changes in the abundance of related proteins and key compounds. The integration of global proteomics and transcriptomic data further revealed that post-transcriptional events are important for temporal regulation of processes such as photosynthesis in Cyanothece 51142. This analysis is the first comprehensive report on global quantitative proteomics in a unicellular diazotrophic cyanobacterium and uncovers novel findings about diurnal rhythms.
authors.affiliation: Department of Biology, Washington University, St Louis, Missouri, United States of America.
authors.forename: Jana
authors.initials: J
authors.lastname: Stöckel
authors.forename: Jon M
authors.initials: JM
authors.lastname: Jacobs
authors.forename: Thanura R
authors.initials: TR
authors.lastname: Elvitigala
authors.forename: Michelle
authors.initials: M
authors.lastname: Liberton
authors.forename: Eric A
authors.initials: EA
authors.lastname: Welsh
authors.forename: Ashoka D
authors.initials: AD
authors.lastname: Polpitiya
authors.forename: Marina A
authors.initials: MA
authors.lastname: Gritsenko
authors.forename: Carrie D
authors.initials: CD
authors.lastname: Nicora
authors.forename: David W
authors.initials: DW
authors.lastname: Koppenaal
authors.forename: Richard D
authors.initials: RD
authors.lastname: Smith
authors.forename: Himadri B
authors.initials: HB
authors.lastname: Pakrasi
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002940:Circadian Rhythm / Q000235:genetics / Q000502:physiology*; D016000:Cluster Analysis; D000458:Cyanobacteria / Q000235:genetics / Q000378:metabolism; D046889:Cyanothece / Q000235:genetics* / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D016680:Genome, Bacterial; D008027:Light; D055442:Metabolome; D009586:Nitrogen Fixation / Q000502:physiology; D017440:Photoperiod; D010788:Photosynthesis / Q000235:genetics / Q000502:physiology; D014176:Protein Biosynthesis / Q000235:genetics / Q000502:physiology*; D020543:Proteome / Q000032:analysis / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D020543:Proteome