The crystal structure of the heme d biosynthesis-associated small c-type cytochrome NirC reveals mixed oligomeric states in crystallo.
Cast your vote
You can rate an item by clicking the amount of stars they wish to award to this item.
When enough users have cast their vote on this item, the average rating will also be shown.
Your vote was cast
Thank you for your feedback
Thank you for your feedback
MetadataShow full item record
AbstractMonoheme c-type cytochromes are important electron transporters in all domains of life. They possess a common fold hallmarked by three α-helices that surround a covalently attached heme. An intriguing feature of many monoheme c-type cytochromes is their capacity to form oligomers by exchanging at least one of their α-helices, which is often referred to as 3D domain swapping. Here, the crystal structure of NirC, a c-type cytochrome co-encoded with other proteins involved in nitrite reduction by the opportunistic pathogen Pseudomonas aeruginosa, has been determined. The crystals diffracted anisotropically to a maximum resolution of 2.12 Å (spherical resolution of 2.83 Å) and initial phases were obtained by Fe-SAD phasing, revealing the presence of 11 NirC chains in the asymmetric unit. Surprisingly, these protomers arrange into one monomer and two different types of 3D domain-swapped dimers, one of which shows pronounced asymmetry. While the simultaneous observation of monomers and dimers probably reflects the interplay between the high protein concentration required for crystallization and the structural plasticity of monoheme c-type cytochromes, the identification of conserved structural motifs in the monomer together with a comparison with similar proteins may offer new leads to unravel the unknown function of NirC.
CitationActa Crystallogr D Struct Biol. 2020;76(Pt 4):375-384. doi:10.1107/S2059798320003101.
AffiliationHZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany.
Publisher: International Union of Crystallography
The following license files are associated with this item:
- Creative Commons
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-ShareAlike 4.0 International
- Crystal structure of NirF: insights into its role in heme d(1) biosynthesis.
- Authors: Klünemann T, Nimtz M, Jänsch L, Layer G, Blankenfeldt W
- Issue date: 2021 Jan
- Two c-type cytochromes, NirM and NirC, encoded in the nir gene cluster of Pseudomonas aeruginosa act as electron donors for nitrite reductase.
- Authors: Hasegawa N, Arai H, Igarashi Y
- Issue date: 2001 Nov 16
- N-terminal arm exchange is observed in the 2.15 A crystal structure of oxidized nitrite reductase from Pseudomonas aeruginosa.
- Authors: Nurizzo D, Silvestrini MC, Mathieu M, Cutruzzolà F, Bourgeois D, Fülöp V, Hajdu J, Brunori M, Tegoni M, Cambillau C
- Issue date: 1997 Sep 15
- Domain-swapped dimer of Pseudomonas aeruginosa cytochrome c551: structural insights into domain swapping of cytochrome c family proteins.
- Authors: Nagao S, Ueda M, Osuka H, Komori H, Kamikubo H, Kataoka M, Higuchi Y, Hirota S
- Issue date: 2015
- Protein surface charge effect on 3D domain swapping in cells for c-type cytochromes.
- Authors: Yang H, Yamanaka M, Nagao S, Yasuhara K, Shibata N, Higuchi Y, Hirota S
- Issue date: 2019 Nov