title: De novo sequence analysis of N-terminal sulfonated peptides after in-gel guanidination.
abstract: In this protocol, we describe an approach in which two-dimensional electrophoresis (2DE)-separated proteins are guanidinated in-gel prior to enzymatic cleavage. In contrast to previously described techniques, this procedure allows the extracted tryptic peptides to be N-terminally sulfonated without any further sample purification. The protocol was applied on a proteomic study of 2DE-separated proteins from Halorhodospira halophila, an extremophilic eubacterium with an unsequenced genome at the moment of analysis.
authors.affiliation: Laboratory of Protein Biochemistry and Protein Engineering, Department of Biochemistry, Physiology and Microbiology, Ghent University, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium.
authors.forename: Kjell
authors.initials: K
authors.lastname: Sergeant
authors.forename: Jozef Van
authors.initials: JV
authors.lastname: Beeumen
authors.forename: Bart
authors.initials: B
authors.lastname: Samyn
mesh_terms: D000465:Algorithms; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D019791:Guanidine / Q000737:chemistry*; D020607:Halorhodospira halophila / Q000737:chemistry; D010455:Peptides / Q000032:analysis*; D020539:Sequence Analysis, Protein / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013451:Sulfonic Acids / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D010455:Peptides; D013451:Sulfonic Acids; D019791:Guanidine