9ilt

Crystal structure of alternative complex III from Chloroflexus aurantiacus

spinqualitylabelsall models 9ilt, resolution 3.25Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 9ilt is a 8 chain structure with sequence from Chloroflexus aurantiacus J-10-fl. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 3.25Å Ligands: HEC Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function A9WEV4_CHLAA Publication Abstract from PubMed Alternative complex III (ACIII) is a multi-subunit quinol:electron acceptor oxidoreductase that couples quinol oxidation with transmembrane proton translocation in bacterial respiratory and photosynthetic electron transport chains. Four ACIII cryoelectron microscopy (cryo-EM) structures are known. However, the effects of cryo-EM versus X-ray crystallography structure determination on ACIII structure are unclear. Here, we report a 3.25 A crystal structure of photosynthetic ACIII from Chloroflexus aurantiacus (CaACIIIp), revealing eight subunits (ActA-G and I) with four iron-sulfur clusters and six c-type hemes, a menaquinol-binding site, and two proton translocation passages. Structural comparisons with the previously reported cryo-EM structures reveal slight local conformational changes in the solvent-exposed regions of ActB, ActD, ActG, and the transmembrane (TM) helix of subunit I. The regions conferring structural flexibility possess low sequence conservation across species. However, the core functional modules containing the menaquinol-binding pocket, redox centers, and proton translocation passages remain unchanged, preserving the enzyme's activity. Crystal structure of the alternative complex III from the phototrophic bacterium Chloroflexus aurantiacus.,Wu W, Fang H, He H, Wu J, Gong Z, Li C, Pei X, Xu X Structure. 2025 Jan 2;33(1):29-38.e2. doi: 10.1016/j.str.2024.10.014. Epub 2024 , Nov 4. PMID:39500318 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA