title: A preliminary investigation of the Nostoc punctiforme proteome.
abstract: Nostoc punctiforme ATCC 29133 is a filamentous terrestrial cyanobacterium (prokaryote) that expresses several different phenotypes in response to environmental cues. When grown in nitrogen-deficient media the most abundant proteins in addition to phycobiliproteins were superoxide dismutase, ATP synthase, and peptidyl-prolyl cis-trans isomerases. A methylated peptide from an akinete marker protein was also identified, suggesting that methylation could potentially play a regulatory role through signaling. C-phycocyanin alpha-chain was methylated at the C-terminal end of the protein and tandem mass spectrometric data also identified peptides that were deamidated. Since a significant number of putative polyketide/non-ribosomal peptide synthase genes are present in the annotated genome, an analysis of a methanolic extract of whole cells was also performed, and a series of nostopeptolides were identified.
authors.affiliation: Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Hunsucker
authors.forename: Karsten
authors.initials: K
authors.lastname: Klage
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Slaughter
authors.forename: Malcolm
authors.initials: M
authors.lastname: Potts
authors.forename: Richard F
authors.initials: RF
authors.lastname: Helm
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000032:analysis* / Q000737:chemistry; D000458:Cyanobacteria / Q000737:chemistry*; D030562:Databases, Protein; D015180:Electrophoresis, Gel, Two-Dimensional; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D010456:Peptides, Cyclic / Q000737:chemistry; D020543:Proteome / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods
chemical_list: D001426:Bacterial Proteins; D010446:Peptide Fragments; D010456:Peptides, Cyclic; D020543:Proteome