Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/79865
Type: Artigo de periódico
Title: Role of polymer-protein interaction on partitioning pattern of bovine pancreatic trypsinogen and alpha-chymotrypsinogen in polyethyleneglycol/sodium tartrate aqueous two-phase systems
Author: Malpiedi, LP
Pico, GA
Loh, W
Nerli, BB
Abstract: The partitioning pattern of bovine trypsinogen (TRPz) and alpha-chymotrypsinogen (ChTRPz) was investigated in a low impact aqueous two-phase system formed by polyethyleneglycol (PEG) and sodium tartrate (NaTart) pH 5.00. ChTRPz exhibited higher partition coefficients than TRPz did in all the assayed systems. The decrease in PEG molecular weight and the increase in tie line length were observed to displace the partitioning equilibrium of both proteins to the top phase, while phase volume ratios in the range 0.5-1.5 showed not to affect protein partitioning behaviour. Systems formed by PEG of molecular weight 600 with composition corresponding to a high tie line length (PEG 12.93%, w/w and NaTart 21.20%, w/w) are able to recover most of both zymogens in the polymer-enriched phase. A crucial role of PEG-protein interaction in the partitioning mechanism was evidenced by isothermal calorimetric titrations. The major content of highly exposed tryptophan rests, present in ChTRPz molecule, could be considered to be determinant of its higher partition coefficient due to a selective charge transfer interaction with PEG molecule. A satisfactory correlation between partition coefficient and protein surface hydrophobicity was observed in systems formed with PEGs of molecular weight above 4000, this finding being relevant in the design of an extraction process employing aqueous two-phase systems. (C) 2010 Elsevier B.V. All rights reserved.
Subject: Trypsinogen
Alpha-chymotrypsinogen
Isothermal titration calorimetry
Aqueous two-phase systems
Protein average surface hydrophobicity
Country: Holanda
Editor: Elsevier Science Bv
Rights: fechado
Identifier DOI: 10.1016/j.jchromb.2010.05.021
Date Issue: 2010
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
WOS000279509300016.pdf362.7 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.