1UX9

Mapping protein matrix cavities in human cytoglobin through Xe atom binding: a crystallographic investigation

Summary for 1UX9

• Entry DOI: 10.2210/pdb1ux9/pdb
• Related: 1UMO 1URV 1URY 1UT0
• Descriptor: CYTOGLOBIN, XENON, PROTOPORPHYRIN IX CONTAINING FE, ... (5 entities in total)
• Functional Keywords: oxygen transport, oxygen storage/transport, heme, transport
• Biological source: HOMO SAPIENS
• Cellular location: Cytoplasm (By similarity): Q8WWM9
• Total number of polymer chains: 2
• Total formula weight: 45378.89

Authors

De Sanctis, D.,Dewilde, S.,Pesce, A.,Moens, L.,Ascenzi, P.,Hankeln, T.,Burmester, T.,Bolognesi, M. (deposition date: 2004-02-23, release date: 2004-06-01, Last modification date: 2024-05-08)

Primary citation

De Sanctis, D.,Dewilde, S.,Pesce, A.,Moens, L.,Ascenzi, P.,Hankeln, T.,Burmester, T.,Bolognesi, M.
Mapping Protein Matrix Cavities in Human Cytoglobin Through Xe Atom Binding
Biochem.Biophys.Res.Commun., 316:1217-, 2004

PubMed 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.

PubMed: 15044115
DOI: 10.1016/J.BBRC.2004.03.007

Experimental method

X-RAY DIFFRACTION (2.4 Å)