title: Hydrophobin-coated plates as matrix-assisted laser desorption/ionization sample support for peptide/protein analysis.
abstract: Fungal hydrophobins are amphipathic self-assembling proteins. Vmh2 hydrophobin, prepared from mycelial cultures of the basidiomycete fungus Pleurotus ostreatus, spontaneously forms a stable and homogeneous layer on solid surfaces and is able to strongly absorb proteins even in their active forms. In this work, we have exploited the Vmh2 self-assembled layer as a novel coating of a matrix-assisted laser desorption/ionization (MALDI) steel sample-loading plate. Mixtures of standard proteins, as well as tryptic peptides, in the nanomolar-femtomolar range were analyzed in the presence of salts and denaturants. As evidence on a real complex sample, crude human serum was also analyzed and spectra over a wide mass range were acquired. A comparison of this novel coating method with both standard desalting techniques and recently reported on-plate desalting methods was also performed. The results demonstrate that Vmh2 coating of MALDI plates allows for a very simple and effective desalting method suitable for development of lab-on-a-plate platforms focused on proteomic applications.
authors.affiliation: Department of Chemical Sciences, University of Naples "Federico II", 80126 Naples, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Longobardi
authors.affiliation: Department of Chemical Sciences, University of Naples "Federico II", 80126 Naples, Italy.
authors.forename: Alfredo Maria
authors.initials: AM
authors.lastname: Gravagnuolo
authors.affiliation: Unit of Naples-Institute for Microelectronics and Microsystems, National Council of Research, 80131 Naples, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Rea
authors.affiliation: Unit of Naples-Institute for Microelectronics and Microsystems, National Council of Research, 80131 Naples, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: De Stefano
authors.affiliation: Department of Chemical Sciences, University of Naples "Federico II", 80126 Naples, Italy.
authors.forename: Gennaro
authors.initials: G
authors.lastname: Marino
authors.affiliation: Department of Chemical Sciences, University of Naples "Federico II", 80126 Naples, Italy. Electronic address: giardina@unina.it.
authors.forename: Paola
authors.initials: P
authors.lastname: Giardina
mesh_terms: D001798:Blood Proteins / Q000032:analysis*; D005656:Fungal Proteins / Q000737:chemistry*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D055767:Immobilized Proteins / Q000737:chemistry*; D010455:Peptides / Q000032:analysis*; D020076:Pleurotus / Q000737:chemistry*; D012492:Salts / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D001798:Blood Proteins; D005656:Fungal Proteins; D055767:Immobilized Proteins; D010455:Peptides; D012492:Salts
keywords: Fungal proteins; Lab-on-a-plate; Self-assembly; Thin films