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Neutron diffraction studies on rubredoxin from Pyrococcus furiosus.

Robert Bau
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Abstract

Single-crystal neutron diffraction data up to a resolution of 1.5 A have been collected at room temperature on two forms of rubredoxin using the BIX-3 diffractometer at the JRR-3 reactor of the Japan Atomic Energy Research Institute (JAERI). Rubredoxin is a small iron-sulfur redox protein with 53 amino acid residues, and the source of this particular protein is the hyperthermophile Pyrococcus furiosus, a microorganism that normally lives at temperatures near that of boiling water. Data were collected on crystals of the wild-type protein and on a mutant in which three of the residues have been replaced. In this paper we will be describing several sets of results arising from these high-resolution neutron structure determinations: (a) the H/D exchange pattern of the N-H bonds of the main backbone, which give information about which regions of the molecule are more exposed to solvent; (b) the orientations of some of the O-D bonds in the protein, information which is often not obtainable from X-ray results; (c) the structure and appearance of water molecules in the protein crystals; and (d) some structural features which may help rationalize the remarkable thermal stability of the wild-type protein from this intriguing microorganism

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Binding SitesDeuteriumHydrogen BondingModels, MolecularMolecular WeightNeutron DiffractionProtein BindingProtein ConformationProtein DenaturationProtein Structure, SecondaryPyrococcus furiosusRubredoxinsTemperatureWaterJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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Robert Bau. 2003-11-28. Neutron diffraction studies on rubredoxin from Pyrococcus furiosus.. https://doi.org/10.1107/s0909049503024178

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