title: Liquid-chromatographic and mass-spectrometric identification of lens proteins using microwave-assisted digestion with trypsin-immobilized magnetic nanoparticles.
abstract: We used a newly developed method combining trypsin-immobilized magnetic nanoparticles (TIMNs) and microwave-assisted protein digestion to study the proteins of human lens tissue. The digested proteins were identified by liquid chromatography and mass spectrometry. The lens proteins were digested under optimized conditions (digestion time 1 min, microwave power 400 W, trypsin-to-protein ratio 1:5) determined using bovine serum albumin as the standard protein, before liquid-chromatographic and mass-spectrometric analysis. Twenty-six proteins were identified with the new digestion method compared with 11 proteins identified with traditional in-solution digestion (12h). gamma-Crystallin, beta-crystallin, and superoxide dismutase 1 proteins, identified with the microwave-assisted method but not the traditional method, are related to cataract development according to some studies. The TIMNs were easily separated from the digestion products. This new digestion method could prove extremely useful for large-scale proteomic analyses.
authors.affiliation: Department of Ophthalmology, Eye & ENT Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, PR China.
authors.forename: Aizhu
authors.initials: A
authors.lastname: Miao
authors.forename: Ying
authors.initials: Y
authors.lastname: Dai
authors.forename: Yinghong
authors.initials: Y
authors.lastname: Ji
authors.forename: Yongxiang
authors.initials: Y
authors.lastname: Jiang
authors.forename: Yi
authors.initials: Y
authors.lastname: Lu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods*; D003459:Crystallins / Q000032:analysis* / Q000737:chemistry / Q000235:genetics; D004800:Enzymes, Immobilized / Q000737:chemistry; D006801:Humans; D008280:Magnetics; D013058:Mass Spectrometry / Q000379:methods*; D051379:Mice; D018345:Mice, Knockout; D008872:Microwaves; D008969:Molecular Sequence Data; D053758:Nanoparticles / Q000737:chemistry*; D040901:Proteomics / Q000379:methods*; D014357:Trypsin / Q000737:chemistry
chemical_list: D003459:Crystallins; D004800:Enzymes, Immobilized; D014357:Trypsin