Journal:Acta Cryst D:S2059798320003101
From Proteopedia
(Difference between revisions)
| (6 intermediate revisions not shown.) | |||
| Line 4: | Line 4: | ||
<hr/> | <hr/> | ||
<b>Molecular Tour</b><br> | <b>Molecular Tour</b><br> | ||
| - | NirC is a monoheme c-type cytochrome co-encoded with other proteins involved in nitrite reduction. It possesses the common fold hallmarked of three α-helices that surround a covalently attached heme. Its crystals diffracted anisotropically to a maximum resolution of 2.12 Å (spherical resolution 2.83 Å) and initial phases were obtained by Fe-SAD phasing, revealing the presence of eleven NirC chains in the asymmetric unit. Surprisingly, these protomers arrange into one monomer and two different types of 3D-domain-swapped dimers, one showing pronounced asymmetry. While the simultaneous observation of monomers and dimers probably reflects the interplay between high protein concentration required for crystallization and the structural plasticity of NirC, the identification of conserved structural motifs in the monomer together with a comparison to similar proteins suggest an involvement of NirC in heme ''d<sub>1</sub>'' biosynthesis. | + | NirC is a monoheme c-type cytochrome co-encoded with other proteins involved in nitrite reduction. It possesses the common fold hallmarked of three α-helices that surround a covalently attached heme. Its crystals diffracted anisotropically to a maximum resolution of 2.12 Å (spherical resolution 2.83 Å) and initial phases were obtained by Fe-SAD phasing, revealing the presence of eleven NirC chains in the asymmetric unit (PDB entry [[6tp9]]). Surprisingly, these protomers arrange into one monomer and two different types of 3D-domain-swapped dimers, one showing pronounced asymmetry. While the simultaneous observation of monomers and dimers probably reflects the interplay between high protein concentration required for crystallization and the structural plasticity of NirC, the identification of conserved structural motifs in the monomer together with a comparison to similar proteins suggest an involvement of NirC in heme ''d<sub>1</sub>'' biosynthesis. |
The NirC monomer shown as a cartoon with residues at a maximum distance of 4 Å to the covalently attached heme presented as sticks: | The NirC monomer shown as a cartoon with residues at a maximum distance of 4 Å to the covalently attached heme presented as sticks: | ||
| - | *<scene name='83/837917/Cv/ | + | *<scene name='83/837917/Cv/19'>First view</scene>. |
| - | *<scene name='83/837917/Cv/ | + | *<scene name='83/837917/Cv/20'>Second view after rotation</scene>. |
| + | Colours are based on sequence conservation as defined by Consurf. {{Template:ColorKey_ConSurf_NoYellow_NoGray}} | ||
Depiction of the two different oligomerization states found in the crystal structure of NirC: | Depiction of the two different oligomerization states found in the crystal structure of NirC: | ||
| Line 17: | Line 18: | ||
The residues of the hinge loop: | The residues of the hinge loop: | ||
*<scene name='83/837917/Cv/13'>Far-Dimer</scene>. | *<scene name='83/837917/Cv/13'>Far-Dimer</scene>. | ||
| + | *<scene name='83/837917/Cv/15'>Monomer</scene>. | ||
| + | *<scene name='83/837917/Cv/14'>Close-Dimer</scene>. | ||
| + | '''PDB reference:''' c-type cytochrome NirC [[6tp9]] | ||
<b>References</b><br> | <b>References</b><br> | ||
Current revision
| |||||||||||
This page complements a publication in scientific journals and is one of the Proteopedia's Interactive 3D Complement pages. For aditional details please see I3DC.
