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Title: Structure of a novel dodecaheme cytochrome c from Geobacter sulfurreducens reveals an extended 12 nm protein with interacting hemes.

Abstract

Multiheme cytochromes c are important in electron transfer pathways in reduction of both soluble and insoluble Fe(III) by Geobacter sulfurreducens. We determined the crystal structure at 3.2 {angstrom} resolution of the first dodecaheme cytochrome c (GSU1996) along with its N-terminal and C-terminal hexaheme fragments at 2.6 and 2.15 {angstrom} resolution, respectively. The macroscopic reduction potentials of the full-length protein and its fragments were measured. The sequence of GSU1996 can be divided into four c{sub 7}-type domains (A, B, C and D) with homology to triheme cytochromes c{sub 7}. In cytochromes c{sub 7} all three hemes are bis-His coordinated, whereas in c{sub 7}-type domains the last heme is His-Met coordinated. The full-length GSU1996 has a 12 nm long crescent shaped structure with the 12 hemes arranged along a polypeptide to form a 'nanowire' of hemes; it has a modular structure. Surprisingly, while the C-terminal half of the protein consists of two separate c{sub 7}-type domains (C and D) connected by a small linker, the N-terminal half of the protein has two c{sub 7}-type domains (A and B) that form one structural unit. This is also observed in the AB fragment. There is an unexpected interaction between the hemes at the interfacemore » of domains A and B, which form a heme-pair with nearly parallel stacking of their porphyrin rings. The hemes adjacent to each other throughout the protein are within van der Waals distance which enables efficient electron exchange between them. For the first time, the structural details of c{sub 7}-type domains from one multiheme protein were compared.« less

Authors:
; ; ; ; ; ; ; ; ; ;  [1];  [2];  [2]
  1. (Biosciences Division)
  2. (
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1020667
Report Number(s):
ANL/BIO/JA-68726
Journal ID: 1047-8477; TRN: US201116%%565
DOE Contract Number:  
DE-AC02-06CH11357
Resource Type:
Journal Article
Journal Name:
J. Struct. Biol.
Additional Journal Information:
Journal Volume: 174; Journal Issue: 1 ; Apr. 2011
Country of Publication:
United States
Language:
ENGLISH
Subject:
59 BASIC BIOLOGICAL SCIENCES; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; CRYSTAL STRUCTURE; CYTOCHROMES; ELECTRON EXCHANGE; ELECTRON TRANSFER; HEME; MODULAR STRUCTURES; POLYPEPTIDES; PORPHYRINS; PROTEINS; RESOLUTION

Citation Formats

Pokkuluri, P. R., Londer, Y. Y., Duke, N. E. C., Pessanha, M., Yang, X., Orshonsky, V., Orshonsky, L., Erickson, J., Zagyansky, Y., Salgueiro, C. A., Schiffer, M., Requimte-CQFB), and Univ. nova de Lisboa). Structure of a novel dodecaheme cytochrome c from Geobacter sulfurreducens reveals an extended 12 nm protein with interacting hemes.. United States: N. p., 2011. Web. doi:10.1016/j.jsb.2010.11.022.
Pokkuluri, P. R., Londer, Y. Y., Duke, N. E. C., Pessanha, M., Yang, X., Orshonsky, V., Orshonsky, L., Erickson, J., Zagyansky, Y., Salgueiro, C. A., Schiffer, M., Requimte-CQFB), & Univ. nova de Lisboa). Structure of a novel dodecaheme cytochrome c from Geobacter sulfurreducens reveals an extended 12 nm protein with interacting hemes.. United States. doi:10.1016/j.jsb.2010.11.022.
Pokkuluri, P. R., Londer, Y. Y., Duke, N. E. C., Pessanha, M., Yang, X., Orshonsky, V., Orshonsky, L., Erickson, J., Zagyansky, Y., Salgueiro, C. A., Schiffer, M., Requimte-CQFB), and Univ. nova de Lisboa). Fri . "Structure of a novel dodecaheme cytochrome c from Geobacter sulfurreducens reveals an extended 12 nm protein with interacting hemes.". United States. doi:10.1016/j.jsb.2010.11.022.
@article{osti_1020667,
title = {Structure of a novel dodecaheme cytochrome c from Geobacter sulfurreducens reveals an extended 12 nm protein with interacting hemes.},
author = {Pokkuluri, P. R. and Londer, Y. Y. and Duke, N. E. C. and Pessanha, M. and Yang, X. and Orshonsky, V. and Orshonsky, L. and Erickson, J. and Zagyansky, Y. and Salgueiro, C. A. and Schiffer, M. and Requimte-CQFB) and Univ. nova de Lisboa)},
abstractNote = {Multiheme cytochromes c are important in electron transfer pathways in reduction of both soluble and insoluble Fe(III) by Geobacter sulfurreducens. We determined the crystal structure at 3.2 {angstrom} resolution of the first dodecaheme cytochrome c (GSU1996) along with its N-terminal and C-terminal hexaheme fragments at 2.6 and 2.15 {angstrom} resolution, respectively. The macroscopic reduction potentials of the full-length protein and its fragments were measured. The sequence of GSU1996 can be divided into four c{sub 7}-type domains (A, B, C and D) with homology to triheme cytochromes c{sub 7}. In cytochromes c{sub 7} all three hemes are bis-His coordinated, whereas in c{sub 7}-type domains the last heme is His-Met coordinated. The full-length GSU1996 has a 12 nm long crescent shaped structure with the 12 hemes arranged along a polypeptide to form a 'nanowire' of hemes; it has a modular structure. Surprisingly, while the C-terminal half of the protein consists of two separate c{sub 7}-type domains (C and D) connected by a small linker, the N-terminal half of the protein has two c{sub 7}-type domains (A and B) that form one structural unit. This is also observed in the AB fragment. There is an unexpected interaction between the hemes at the interface of domains A and B, which form a heme-pair with nearly parallel stacking of their porphyrin rings. The hemes adjacent to each other throughout the protein are within van der Waals distance which enables efficient electron exchange between them. For the first time, the structural details of c{sub 7}-type domains from one multiheme protein were compared.},
doi = {10.1016/j.jsb.2010.11.022},
journal = {J. Struct. Biol.},
number = 1 ; Apr. 2011,
volume = 174,
place = {United States},
year = {2011},
month = {4}
}