title: Analytical approach to the metallomic of Nile tilapia (Oreochromis niloticus) liver tissue by SRXRF and FAAS after 2D-PAGE separation: Preliminary results.
abstract: An investigation was made into calcium, iron and zinc in protein spots in samples of Nile tilapia (Oreochromis niloticus) liver tissue obtained after protein separation by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and subsequent qualitative and quantitative evaluation by synchrotron radiation X-ray fluorescence (SRXRF) and Flame Atomic Absorption Spectrometry (FAAS). An analysis of the fluorescence spectra indicated the presence of calcium, iron and zinc in 12, 6 and 8 liver protein spots, respectively. The metal ions found were distributed mainly in proteins with a molar mass of less than 40.00 kDa and more than 12.00 kDa, with pI in the range of 4.70-9.40. The only exception was a spot presenting protein with a molar mass of 10.10 kDa. In addition to calcium, iron and zinc, sulfur and phosphorus - which are non-metals that may be part of the protein structure, were also detected. After microwave-assisted acid mineralization of the proteins spots, a FAAS estimation of the concentration of calcium, iron and zinc ions bound to these proteins indicated a range of 1.08-5.80 mg g(-1), 2.02-8.03 mg g(-1) and 1.60-8.55 mg g(-1), respectively.
authors.affiliation: Faculdade de Medicina Veterinária e Zootecnia/UNESP, Programa de Pós-Graduação em Zootecnia, C. Postal 31, 15385-000 Botucatu, SP, Brazil.
authors.forename: Paula M
authors.initials: PM
authors.lastname: Lima
authors.forename: Renato de C F
authors.initials: Rde C
authors.lastname: Neves
authors.forename: Felipe A
authors.initials: FA
authors.lastname: dos Santos
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Pérez
authors.forename: Marcelo O A
authors.initials: MO
authors.lastname: da Silva
authors.forename: Marco A Z
authors.initials: MA
authors.lastname: Arruda
authors.forename: Gustavo R
authors.initials: GR
authors.lastname: de Castro
authors.forename: Pedro M
authors.initials: PM
authors.lastname: Padilha
mesh_terms: D000818:Animals; D002118:Calcium; D023681:Cichlids / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D007501:Iron; D008099:Liver / Q000737:chemistry*; D008667:Metalloproteins / Q000032:analysis*; D008670:Metals / Q000032:analysis*; D013052:Spectrometry, X-Ray Emission / Q000379:methods; D013054:Spectrophotometry, Atomic / Q000379:methods; D015032:Zinc
chemical_list: D008667:Metalloproteins; D008670:Metals; D007501:Iron; D015032:Zinc; D002118:Calcium