1FT5

CRYSTAL STRUCTURE OF THE OXIDIZED STATE OF CYTOCHROME C554 FROM NITROSOMONAS EUROPAEA

Summary for 1FT5

• Entry DOI: 10.2210/pdb1ft5/pdb
• Related: 1BVB 1FT6
• Descriptor: CYTOCHROME C554, PHOSPHATE ION, PROTOPORPHYRIN IX CONTAINING FE, ... (4 entities in total)
• Functional Keywords: heme-stacking, electron transport
• Biological source: Nitrosomonas europaea
• Total number of polymer chains: 1
• Total formula weight: 26407.76

Authors

Iverson, T.M.,Arciero, D.M.,Hooper, A.B.,Rees, D.C. (deposition date: 2000-09-11, release date: 2000-09-20, Last modification date: 2024-10-16)

Primary citation

Iverson, T.M.,Arciero, D.M.,Hooper, A.B.,Rees, D.C.
High-resolution structures of the oxidized and reduced states of cytochrome c554 from Nitrosomonas europaea.
J.Biol.Inorg.Chem., 6:390-397, 2001

PubMed Abstract: Cytochrome c554 (cyt c554) is a tetra-heme cytochrome involved in the oxidation of NH3 by Nitrosomonas europaea. The X-ray crystal structures of both the oxidized and dithionite-reduced states of cyt c554 in a new, rhombohedral crystal form have been solved by molecular replacement, at 1.6 A and 1.8 A resolution, respectively. Upon reduction, the conformation of the polypeptide chain changes between residues 175 and 179, which are adjacent to hemes III and IV. Cyt c554 displays conserved heme-packing motifs that are present in other heme-containing proteins. Comparisons to hydroxylamine oxidoreductase, the electron donor to cyt c554, and cytochrome c nitrite reductase, an enzyme involved in nitrite ammonification, reveal substantial structural similarity in the polypeptide chain surrounding the heme core environment. The structural determinants of these heme-packing motifs extend to the buried water molecules that hydrogen bond to the histidine ligands to the heme iron. In the original structure determination of a tetragonal crystal form, a cis peptide bond between His129 and Phe130 was identified that appeared to be stabilized by crystal contacts. In the rhombohedral crystal form used in the present high-resolution structure determination, this peptide bond adopts the trans conformation, but with disallowed angles of phi and psi.

PubMed: 11372197
DOI: 10.1007/s007750100213

Experimental method

X-RAY DIFFRACTION (1.6 Å)