Neutron crystallographic study on rubredoxin from Pyrococcus furiosus by BIX-3, a single-crystal diffractometer for biomacromolecules

Document Type

Article

Publication Date

2004

Abstract

The structure of a partially deuterated rubredoxin from the hyperthermophilic archaeon Pyrococcus furiosus, an organism that grows optimally at 100°C, was determined by using the neutron single-crystal diffractometer dedicated for biological macromolecules (BIX-3) at the JRR-3M reactor of the Japan Atomic Energy Research Institute. Data were collected at room temperature up to a resolution of 1.5 Å, and the completeness factor of the data set was 81.9%. The model contains 306 H and 50 D atoms. A total of 37 hydration water molecules were identified, with 15 having all three atoms fully located and the remaining D2O molecules partially defined. The model has been refined to final agreement factors of R = 18.6% and Rfree = 21.7%. Several orientations of the O-D bonds of side chains, whose assignments from x-ray data were previously ambiguous, were clearly visible in the neutron structure. Although most backbone N-H bonds had undergone some degree of H/D exchange throughout the rubredoxin molecule, 5 H atom positions still had distinctly negative (H) peaks. The neutron Fourier maps clearly showed the details of an extensive set of H bonds involving the ND3 + terminus that may contribute to the unusual thermostability of this molecule.

Publication Title

Proceedings of the National Academy of Sciences of the United States of America

Volume

101

First Page

11215

Last Page

11220

Comments

This article was published in Proceedings of the National Academy of Sciences of the United States of America, Volume 101, Issue 31, Pages 11215-11220.

The published version is available at http://dx.doi.org/10.1073/pnas.0403807101.

Copyright © 2004 National Academy of Sciences.

This document is currently not available here.

COinS