Water-in-Oil Micro-Emulsion Enhances the Secondary Structure of a Protein by Confinement
Contribuinte(s) |
UNIVERSIDADE DE SÃO PAULO |
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Data(s) |
21/10/2013
21/10/2013
2012
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Resumo |
A scheme is presented in which an organic solvent environment in combination with surfactants is used to confine a natively unfolded protein inside an inverse microemulsion droplet. This type of confinement allows a study that provides unique insight into the dynamic structure of an unfolded, flexible protein which is still solvated and thus under near-physiological conditions. In a model system, the protein osteopontin (OPN) is used. It is a highly phosphorylated glycoprotein that is expressed in a wide range of cells and tissues for which limited structural analysis exists due to the high degree of flexibility and large number of post-translational modifications. OPN is implicated in tissue functions, such as inflammation and mineralisation. It also has a key function in tumour metastasis and progression. Circular dichroism measurements show that confinement enhances the secondary structural features of the protein. Small-angle X-ray scattering and dynamic light scattering show that OPN changes from being a flexible protein in aqueous solution to adopting a less flexible and more compact structure inside the microemulsion droplets. This novel approach for confining proteins while they are still hydrated may aid in studying the structure of a wide range of natively unfolded proteins. Danish National Advanced Technology Foundation through the ProSURF platform (Protein-Based Functionalisation of Surfaces) Danish National Advanced Technology Foundation through the ProSURF platform (ProteinBased Functionalisation of Surfaces) iNANO center from the Danish Research Councils iNANO center from the Danish Research Councils Villum Kahn Rasmussen Foundation Villum Kahn Rasmussen Foundation Lundbeck Foundation Lundbeck Foundation Carlsberg Foundation Carlsberg Foundation |
Identificador |
CHEMPHYSCHEM, WEINHEIM, v. 13, n. 13, supl. 1, Part 2, pp. 3179-3184, SEP 17, 2012 1439-4235 http://www.producao.usp.br/handle/BDPI/35191 10.1002/cphc.201200295 |
Idioma(s) |
eng |
Publicador |
WILEY-V C H VERLAG GMBH WEINHEIM |
Relação |
CHEMPHYSCHEM |
Direitos |
restrictedAccess Copyright WILEY-V C H VERLAG GMBH |
Palavras-Chave | #CIRCULAR DICHROISM #LIGHT SCATTERING #MICROEMULSIONS #PROTEIN STRUCTURES #X-RAY DIFFRACTION #X-RAY-SCATTERING #HYDRODYNAMIC PROPERTIES #ORGANIC-SOLVENTS #SPECTROSCOPY #OSTEOPONTIN #BIOLOGY #BEAMLINES #MICELLES #POLYMERS #CHEMISTRY, PHYSICAL #PHYSICS, ATOMIC, MOLECULAR & CHEMICAL |
Tipo |
article original article publishedVersion |