title: Evaluation of sample preparation protocols for proteomic analysis of sunflower leaves.
abstract: Six protocols for extraction of proteins from sunflower (Helianthus annuus L.) leaves were evaluated for their abilities in both removing interferents and attaining the best resolution in two-dimensional gel electrophoresis. "Classical" phenol extraction followed by precipitation with ammonium acetate in methanol displayed the most efficient protocol, which allowed the detection of 244 protein spots with ca. 485mug of protein in gel electrophoresis. Tandem mass spectrometry was performed to identify proteins in 61 spots, and cross species identification was used for this task. Proteins from twenty two spots were identified, and 12 of these proteins are up to now not included into the ExPASy sunflower protein databank.
authors.affiliation: Group of Spectrometry, Sample Preparation and Mechanization (GEPAM), Institute of Chemistry, PO Box 6154, University of Campinas, UNICAMP, 13084-862, Campinas, SP, Brazil.
authors.forename: Marcelo Anselmo Oseas
authors.initials: MA
authors.lastname: da Silva
authors.forename: Jerusa Simone
authors.initials: JS
authors.lastname: Garcia
authors.forename: Gustavo Henrique Martins Ferreira
authors.initials: GH
authors.lastname: de Souza
authors.forename: Marcos Nogueira
authors.initials: MN
authors.lastname: Eberlin
authors.forename: Fábio César
authors.initials: FC
authors.lastname: Gozzo
authors.forename: Marco Aurélio Zezzi
authors.initials: MA
authors.lastname: Arruda
mesh_terms: D000595:Amino Acid Sequence; D030562:Databases, Protein; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D004591:Electrophoresis, Polyacrylamide Gel; D006368:Helianthus / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D010940:Plant Proteins / Q000032:analysis / Q000737:chemistry; D020543:Proteome / Q000032:analysis*; D040901:Proteomics / Q000379:methods*; D053719:Tandem Mass Spectrometry
chemical_list: D010940:Plant Proteins; D020543:Proteome