title: Trypsin purification using magnetic particles of azocasein-iron composite.
abstract: This work presents an inexpensive, simple and fast procedure to purify trypsin based on affinity binding with ferromagnetic particles of azocasein composite (mAzo). Crude extract was obtained from intestines of fish Nile tilapia (Oreochromis niloticus) homogenized in buffer (01g tissue/ml). This extract was exposed to 100mg of mAzo and washed to remove unbound proteins by magnetic field. Trypsin was leached off under high ionic strength (3M NaCl). Preparation was achieved containing specific activity about 60 times higher than that of the crude extract. SDS-PAGE showed that the purified protein had molecular weight (24kDa) in concordance with the literature for the Nile tilapia trypsin. The mAzo composite can be reused and applied to purify trypsin from other sources.
authors.affiliation: Laboratório de Imunopatologia Keizo Asami (LIKA) and Departamento de Bioquímica, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil.
authors.forename: Maria Helena Menezes Estevam
authors.initials: MH
authors.lastname: Alves
authors.affiliation: Laboratório de Imunopatologia Keizo Asami (LIKA) and Departamento de Bioquímica, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil.
authors.forename: Gabriela Ayres
authors.initials: GA
authors.lastname: Nascimento
authors.affiliation: Laboratório de Imunopatologia Keizo Asami (LIKA) and Departamento de Bioquímica, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil.
authors.forename: Mariana Paola
authors.initials: MP
authors.lastname: Cabrera
authors.affiliation: Centre of Biological Engineering, University of Minho, Braga, Portugal.
authors.forename: Sara Isabel da Cruz
authors.initials: SI
authors.lastname: Silvério
authors.affiliation: Centre of Biological Engineering, University of Minho, Braga, Portugal.
authors.forename: Clarisse
authors.initials: C
authors.lastname: Nobre
authors.affiliation: Centre of Biological Engineering, University of Minho, Braga, Portugal.
authors.forename: José António
authors.initials: JA
authors.lastname: Teixeira
authors.affiliation: Laboratório de Imunopatologia Keizo Asami (LIKA) and Departamento de Bioquímica, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil. Electronic address: lbcj.br@gmail.com.
authors.forename: Luiz Bezerra
authors.initials: LB
authors.lastname: de Carvalho
mesh_terms: D000818:Animals; D002364:Caseins / Q000737:chemistry*; D005591:Chemical Fractionation; D023681:Cichlids / Q000378:metabolism*; D029941:Fish Proteins / Q000737:chemistry / Q000302:isolation & purification; D007422:Intestines / Q000201:enzymology*; D007501:Iron / Q000737:chemistry; D058185:Magnetite Nanoparticles / Q000737:chemistry; D008970:Molecular Weight; D014357:Trypsin / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D002364:Caseins; D029941:Fish Proteins; D058185:Magnetite Nanoparticles; C026018:azocasein; D007501:Iron; D014357:Trypsin
keywords: Azocasein iron oxides; Enzyme purification; Fish viscera; Proteases