31OX
Cryo-EM structure of the CO dehydrogenase (CODH) subcomplex from Methanosarcina acetivorans
Summary for 31OX
| Entry DOI | 10.2210/pdb31ox/pdb |
| EMDB information | 58600 58601 |
| Descriptor | Acetyl-CoA decarbonylase/synthase complex subunit epsilon 2, Acetyl-CoA decarbonylase/synthase complex subunit alpha 2, IRON/SULFUR CLUSTER, ... (4 entities in total) |
| Functional Keywords | methanogenesis, acetyl-coa, anaerobic metabolism, co dehydrogenase, metal binding protein |
| Biological source | Methanosarcina acetivorans More |
| Total number of polymer chains | 4 |
| Total formula weight | 216366.79 |
| Authors | Zimmer, E.,Reif-Trauttmansdorff, T.,Schuller, J.M. (deposition date: 2026-06-16, release date: 2026-07-29) |
| Primary citation | Zimmer, E.,Reif-Trauttmansdorff, T.,Ciancone, A.,Appelgren, S.,Kahnt, J.,Deobald, D.,Abendroth, F.,Vazquez, O.,Hochberg, G.K.A.,O'Reilly, F.J.,Schuller, J.M. Interface swapping orchestrates carbon transfer in the archaeal acetyl-CoA decarbonylase/synthase. Biorxiv, 2026 Cited by PubMed Abstract: The Wood-Ljungdahl pathway is one of biology's most ancient routes for carbon fixation and energy metabolism, used by organisms such as methanogenic archaea. One of its central metabolic complexes is the acetyl-CoA decarbonylase/synthase (ACDS) complex, catalyzing acetyl-CoA synthesis and cleavage through the coordinated action of carbon monoxide dehydrogenase (CODH), acetyl-CoA synthase (ACS), and corrinoid iron-sulfur protein (CoFeSP). Unlike bacterial CODH/ACS, archaeal ACDS lacks a stable bifunctional CODH-ACS architecture, raising the question of how reactive CO and methyl intermediates are efficiently transferred between catalytic modules. Using cryo-electron microscopy, crosslinking mass spectrometry, small-angle X-ray scattering, and biophysical analyses, we resolved the organization and dynamics of the ~2 MDa archaeal ACDS supercomplex from . We identified CoFeSP as a central architectural scaffold that self-assembles into hexa- to octameric oligomers via a conserved N-terminal region of the CdhD subunit. This scaffold likely tethers CODH and ACS through conserved disordered terminal regions, positioning the catalytic modules in the complex's periphery. We propose a mechanism in which ACS transiently alternates between CODH and CoFeSP, enabling efficient CO and methyl-group transfer without stable binary complexes. This dynamic organization represents a fundamental difference to the stable bifunctional CODH/ACS in bacteria, highlighting how transient interactions enable efficient acetyl-CoA metabolism in archaea. PubMed: 42465409DOI: 10.64898/2026.07.07.736967 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.55 Å) |
Structure validation
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