Separation and identification of soybean leaf proteins by two-dimensional gel electrophoresis and mass spectrometry.
To establish a proteomic reference map for soybean leaves, we separated and identified leaf proteins using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS). Tryptic digests of 260 spots were subjected to peptide mass fingerprinting (PMF) by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS. Fifty-three of these protein spots were identified by searching NCBInr and SwissProt databases using the Mascot search engine. Sixty-seven spots that were not identified by MALDI-TOF-MS analysis were analyzed with liquid chromatography tandem mass spectrometry (LC-MS/MS), and 66 of these spots were identified by searching against the NCBInr, SwissProt and expressed sequence tag (EST) databases. We have identified a total of 71 unique proteins. The majority of the identified leaf proteins are involved in energy metabolism. The results indicate that 2D-PAGE, combined with MALDI-TOF-MS and LC-MS/MS, is a sensitive and powerful technique for separation and identification of soybean leaf proteins. A summary of the identified proteins and their putative functions is discussed.
Xu
Chenping
C
Department of Natural Resource Sciences and Landscape Architecture, University of Maryland, College Park, MD 20742, USA.
Garrett
Wesley M
WM
Sullivan
Joseph
J
Caperna
Thomas J
TJ
Natarajan
Savithiry
S
D000595:Amino Acid Sequence; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D018515:Plant Leaves / Q000737:chemistry*; D030262:Soybean Proteins / Q000032:analysis* / Q000737:chemistry* / Q000302:isolation & purification; D013025:Glycine max / Q000737:chemistry*
D030262:Soybean Proteins