Mapping protein matrix cavities in human cytoglobin through Xe atom binding.

Daniele de Sanctis; Sylvia Dewilde; Alessandra Pesce; Luc Moens; Paolo Ascenzi; Thomas Hankeln; Thorsten Burmester; Martino Bolognesi

doi:10.1016/j.bbrc.2004.03.007

PubMed · 15044115

Mapping protein matrix cavities in human cytoglobin through Xe atom binding.

Daniele de Sanctis·Sylvia Dewilde·Alessandra Pesce·Luc Moens·Paolo Ascenzi·Thomas Hankeln·Thorsten Burmester·Martino Bolognesi

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Abstract

Cytoglobin is the fourth recognized globin type, almost ubiquitously distributed in human tissues; its function is still poorly understood. Cytoglobin displays a core region of about 150 residues, structurally related to hemoglobin and myoglobin, and two extra segments, about 20 residues each, at the N- and C-termini. The core region hosts a large apolar cavity, held to provide a ligand diffusion pathway to/from the heme, and/or ligand temporary docking sites. Here we report the crystal structure (2.4A resolution, R-factor 19.1%) of a human cytoglobin mutant bearing the CysB2(38) --> Ser and CysE9(83) --> Ser substitutions (CYGB*), treated under pressurized xenon. Three Xe atoms bind to the heme distal site region of CYGB* mapping the protein matrix apolar cavity. Despite the conserved globin fold, the cavity found in CYGB* is structured differently from those recognized to play a functional role in myoglobin, neuroglobin, truncated hemoglobins, and Cerebratulus lacteus mini-hemoglobin.

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Binding Sites Computer Simulation Crystallography, X-Ray Cytoglobin Globins Heme Humans Macromolecular Substances Models, Molecular Peroxidases Porosity Protein Binding Protein Conformation Xenon Comparative Study Journal Article Research Support, Non-U.S. Gov't

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Daniele de Sanctis, Sylvia Dewilde, Alessandra Pesce, Luc Moens, Paolo Ascenzi, Thomas Hankeln, Thorsten Burmester, Martino Bolognesi. 2004-04-16. Mapping protein matrix cavities in human cytoglobin through Xe atom binding.. https://doi.org/10.1016/j.bbrc.2004.03.007

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