1GM4

OXIDISED STRUCTURE OF CYTOCHROME C3 FROM DESULFOVIBRIO DESULFURICANS ATCC 27774 at pH 7.6

Summary for 1GM4

• Entry DOI: 10.2210/pdb1gm4/pdb
• Related: 1GMB 3CYR
• Descriptor: CYTOCHROME C3, HEME C, SULFATE ION, ... (4 entities in total)
• Functional Keywords: electron transport, cytochrome
• Biological source: DESULFOVIBRIO DESULFURICANS
• Total number of polymer chains: 1
• Total formula weight: 14188.55

Authors

Bento, I.,Louro, R.,Matias, P.M.,Catarino, T.,Baptista, A.M.,Soares, C.M.,Carrondo, M.A.,Turner, D.L.,Xavier, A.V. (deposition date: 2001-09-10, release date: 2002-09-05, Last modification date: 2024-10-09)

Primary citation

Louro, R.O.,Bento, I.,Matias, P.M.,Catarino, T.,Baptista, A.M.,Soares, C.M.,Carrondo, M.A.,Turner, D.L.,Xavier, A.V.
Conformational Component in the Coupled Transfer of Multiple Electrons and Protons in a Monomeric Tetraheme Cytochrome.
J.Biol.Chem., 276:44044-, 2001

PubMed Abstract: Cell metabolism relies on energy transduction usually performed by complex membrane-spanning proteins that couple different chemical processes, e.g. electron and proton transfer in proton-pumps. There is great interest in determining at the molecular level the structural details that control these energy transduction events, particularly those involving multiple electrons and protons, because tight control is required to avoid the production of dangerous reactive intermediates. Tetraheme cytochrome c(3) is a small soluble and monomeric protein that performs a central step in the bioenergetic metabolism of sulfate reducing bacteria, termed "proton-thrusting," linking the oxidation of molecular hydrogen with the reduction of sulfate. The mechano-chemical coupling involved in the transfer of multiple electrons and protons in cytochrome c(3) from Desulfovibrio desulfuricans ATCC 27774 is described using results derived from the microscopic thermodynamic characterization of the redox and acid-base centers involved, crystallographic studies in the oxidized and reduced states of the cytochrome, and theoretical studies of the redox and acid-base transitions. This proton-assisted two-electron step involves very small, localized structural changes that are sufficient to generate the complex network of functional cooperativities leading to energy transduction, while using molecular mechanisms distinct from those established for other Desulfovibrio sp. cytochromes from the same structural family.

PubMed: 11551953
DOI: 10.1074/JBC.M107136200

Experimental method

X-RAY DIFFRACTION (2.05 Å)