title: Quantitative shotgun proteomics of enriched heterocysts from Nostoc sp. PCC 7120 using 8-plex isobaric peptide tags.
abstract: The filamentous cyanobacterium Nostoc sp. strain PCC 7120 is capable of fixing atmospheric nitrogen. The labile nature of the core process requires the terminal differentiation of vegetative cells to form heterocysts, specialized cells with altered cellular and metabolic infrastructure to mediate the N2-fixing process. We present an investigation targeting the cellular proteomic expression of the heterocysts compared to vegetative cells of a population cultured under N2-fixing conditions. New 8-plex iTRAQ reagents were used on enriched replicate heterocyst and vegetative cells, and replicate N2-fixing and non-N2-fixing filaments to achieve accurate measurements. With this approach, we successfully identified 506 proteins, where 402 had confident quantifications. Observations provided by purified heterocyst analysis enabled the elucidation of the dominant metabolic processes between the respective cell types, while emphasis on the filaments enabled an overall comparison. The level of analysis provided by this investigation presents various tools and knowledge that are important for future development of cyanobacterial biohydrogen production.
authors.affiliation: Biological & Environmental Systems Group, Department of Chemical and Process Engineering, The University of Sheffield, Sheffield S13JD, UK.
authors.forename: Saw Yen
authors.initials: SY
authors.lastname: Ow
authors.forename: Tanai
authors.initials: T
authors.lastname: Cardona
authors.forename: Arnaud
authors.initials: A
authors.lastname: Taton
authors.forename: Ann
authors.initials: A
authors.lastname: Magnuson
authors.forename: Peter
authors.initials: P
authors.lastname: Lindblad
authors.forename: Karin
authors.initials: K
authors.lastname: Stensjö
authors.forename: Phillip C
authors.initials: PC
authors.lastname: Wright
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis* / Q000378:metabolism; D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000032:analysis / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002852:Chromatography, Ion Exchange / Q000379:methods; D002853:Chromatography, Liquid; D045222:Electron Transport Chain Complex Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D009586:Nitrogen Fixation; D046937:Nostoc / Q000166:cytology / Q000378:metabolism*; D010427:Pentose Phosphate Pathway / Q000502:physiology; D020543:Proteome / Q000032:analysis* / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods; D014157:Transcription Factors / Q000032:analysis / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D018797:Cell Cycle Proteins; D045222:Electron Transport Chain Complex Proteins; D020543:Proteome; D014157:Transcription Factors