1OS6

Cytochrome c7 (PpcA) from Geobacter sulfurreducens

Summary for 1OS6

• Entry DOI: 10.2210/pdb1os6/pdb
• Related: 1HH5
• Descriptor: PpcA, SULFATE ION, HEME C, ... (5 entities in total)
• Functional Keywords: mutli-heme cytochrome, ppca, electron transport
• Biological source: Geobacter sulfurreducens
• Total number of polymer chains: 1
• Total formula weight: 10284.42

Authors

Pokkuluri, P.R.,Londer, Y.Y.,Duke, N.E.C.,Long, W.C.,Schiffer, M. (deposition date: 2003-03-18, release date: 2004-02-03, Last modification date: 2024-11-20)

Primary citation

Pokkuluri, P.R.,Londer, Y.Y.,Duke, N.E.,Long, W.C.,Schiffer, M.
Family of cytochrome c7-type proteins from Geobacter sulfurreducens: structure of one cytochrome c7 at 1.45 A resolution.
Biochemistry, 43:849-859, 2004

PubMed Abstract: The structure of a cytochrome c(7) (PpcA) from Geobacter sulfurreducens was determined by X-ray diffraction at 1.45 A resolution; the R factor is 18.2%. The protein contains a three-heme core that is surrounded by 71 amino acid residues. An unusual feature of this cytochrome is that it has 17 lysine residues, but only nine hydrophobic residues that are larger than alanine. The details of the structure are described and compared with those of cytochrome c(7) from Desulfuromonas acetoxidans and with cytochromes c(3). The two cytochrome c(7) molecules have sequences that are 46% identical, but the arrangements of the hemes in the two structures differ; the rms deviation of all alpha-carbons is 2.5 A. These cytochromes can reduce various metal ions. The reduction site of the chromate ion in D. acetoxidans is occupied by a sulfate ion in the crystal structure of PpcA. We identified four additional homologues of cytochrome c(7) in the G. sulfurreducens genome and three polymers of c(7)-type domains. Of the polymers, two have four repeats and one has nine repeats. On the basis of sequence alignments, one of the hemes in each of the cytochrome c(7)-type domains does not have the bis-histidine coordination. The packing of the molecules in the crystal structure of PpcA suggests that the polymers have an elongated conformation and might form a "nanowire".

PubMed: 14744127
DOI: 10.1021/bi0301439

Experimental method

X-RAY DIFFRACTION (1.45 Å)