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Title: Ceruloplasmin revisited: structural and functional roles of various metal cation-binding sites

Abstract

The three-dimensional molecular structure of human serum ceruloplasmin has been reinvestigated using X-ray synchrotron data collected at 100 K from a crystal frozen to liquid-nitrogen temperature. The three-dimensional molecular structure of human serum ceruloplasmin has been reinvestigated using X-ray synchrotron data collected at 100 K from a crystal frozen to liquid-nitrogen temperature. The resulting model, with an increase in resolution from 3.1 to 2.8 Å, gives an overall improvement of the molecular structure, in particular the side chains. In addition, it enables the clear definition of previously unidentified Ca{sup 2+}-binding and Na{sup +}-binding sites. The Ca{sup 2+} cation is located in domain 1 in a configuration very similar to that found in the activated bovine factor Va. The Na{sup +} sites appear to play a structural role in providing rigidity to the three protuberances on the top surface of the molecule. These features probably help to steer substrates towards the mononuclear copper sites prior to their oxidation and to restrict the size of the approaching substrate. The trinuclear copper centre appears to differ from the room-temperature structure in that a dioxygen moiety is bound in a similar way to that found in the endospore coat protein CotA from Bacillus subtilis.

Authors:
 [1];  [2];  [3];  [1];  [4]
  1. Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Apartado 127, 2781-901 Oeiras (Portugal)
  2. Laboratory of Animal Cell Technology, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras (Portugal)
  3. Centre for Biomolecular Sciences, University of St Andrews, North Haugh, St Andrews KY16 9ST, Scotland (United Kingdom)
  4. (United Kingdom)
Publication Date:
OSTI Identifier:
22348017
Resource Type:
Journal Article
Resource Relation:
Journal Name: Acta Crystallographica. Section D: Biological Crystallography; Journal Volume: 63; Journal Issue: Pt 2; Other Information: PMCID: PMC2483498; PUBLISHER-ID: hv5074; PMID: 17242517; OAI: oai:pubmedcentral.nih.gov:2483498; Copyright (c) International Union of Crystallography 2007; This is an open-access article distributed under the terms described at http://journals.iucr.org/services/termsofuse.html.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
Denmark
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CATIONS; CATTLE; CHAINS; CONFIGURATION; COPPER; CRYSTALS; LIQUIDS; MOLECULES; NITROGEN; OXIDATION; OXYGEN; RESOLUTION; SUBSTRATES; SURFACES

Citation Formats

Bento, Isabel, Peixoto, Cristina, Zaitsev, Vjacheslav N., Lindley, Peter F., E-mail: lindley.p@googlemail.com, and Department of Crystallography, Birkbeck College, University of London, Malet Street, London WC1E 7HX. Ceruloplasmin revisited: structural and functional roles of various metal cation-binding sites. Denmark: N. p., 2007. Web. doi:10.1107/S090744490604947X.
Bento, Isabel, Peixoto, Cristina, Zaitsev, Vjacheslav N., Lindley, Peter F., E-mail: lindley.p@googlemail.com, & Department of Crystallography, Birkbeck College, University of London, Malet Street, London WC1E 7HX. Ceruloplasmin revisited: structural and functional roles of various metal cation-binding sites. Denmark. doi:10.1107/S090744490604947X.
Bento, Isabel, Peixoto, Cristina, Zaitsev, Vjacheslav N., Lindley, Peter F., E-mail: lindley.p@googlemail.com, and Department of Crystallography, Birkbeck College, University of London, Malet Street, London WC1E 7HX. Thu . "Ceruloplasmin revisited: structural and functional roles of various metal cation-binding sites". Denmark. doi:10.1107/S090744490604947X.
@article{osti_22348017,
title = {Ceruloplasmin revisited: structural and functional roles of various metal cation-binding sites},
author = {Bento, Isabel and Peixoto, Cristina and Zaitsev, Vjacheslav N. and Lindley, Peter F., E-mail: lindley.p@googlemail.com and Department of Crystallography, Birkbeck College, University of London, Malet Street, London WC1E 7HX},
abstractNote = {The three-dimensional molecular structure of human serum ceruloplasmin has been reinvestigated using X-ray synchrotron data collected at 100 K from a crystal frozen to liquid-nitrogen temperature. The three-dimensional molecular structure of human serum ceruloplasmin has been reinvestigated using X-ray synchrotron data collected at 100 K from a crystal frozen to liquid-nitrogen temperature. The resulting model, with an increase in resolution from 3.1 to 2.8 Å, gives an overall improvement of the molecular structure, in particular the side chains. In addition, it enables the clear definition of previously unidentified Ca{sup 2+}-binding and Na{sup +}-binding sites. The Ca{sup 2+} cation is located in domain 1 in a configuration very similar to that found in the activated bovine factor Va. The Na{sup +} sites appear to play a structural role in providing rigidity to the three protuberances on the top surface of the molecule. These features probably help to steer substrates towards the mononuclear copper sites prior to their oxidation and to restrict the size of the approaching substrate. The trinuclear copper centre appears to differ from the room-temperature structure in that a dioxygen moiety is bound in a similar way to that found in the endospore coat protein CotA from Bacillus subtilis.},
doi = {10.1107/S090744490604947X},
journal = {Acta Crystallographica. Section D: Biological Crystallography},
number = Pt 2,
volume = 63,
place = {Denmark},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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