4FZW

Crystal Structure of the PaaF-PaaG Hydratase-Isomerase Complex from E.coli

Summary for 4FZW

• Entry DOI: 10.2210/pdb4fzw/pdb
• Descriptor: 2,3-dehydroadipyl-CoA hydratase, 1,2-epoxyphenylacetyl-CoA isomerase, GLYCEROL, ... (4 entities in total)
• Functional Keywords: structural genomics, montreal-kingston bacterial structural genomics initiative, bsgi, crotonase fold, enzymes of the phenylacetate degradation pathway, isomerase-lyase complex, isomerase/lyase
• Biological source: Escherichia coli; More
• Total number of polymer chains: 4
• Total formula weight: 115097.91

Authors

Grishin, A.M.,Cygler, M.,Montreal-Kingston Bacterial Structural Genomics Initiative (BSGI) (deposition date: 2012-07-08, release date: 2012-09-19, Last modification date: 2024-02-28)

Primary citation

Grishin, A.M.,Ajamian, E.,Zhang, L.,Rouiller, I.,Bostina, M.,Cygler, M.
Protein-Protein Interactions in the beta-Oxidation Part of the Phenylacetate Utilization Pathway. Crystal Structure of the PaaF-PaaG Hydratase-Isomerase Complex
J.Biol.Chem., 287:37986-37996, 2012

PubMed Abstract: Microbial anaerobic and so-called hybrid pathways for degradation of aromatic compounds contain β-oxidation-like steps. These reactions convert the product of the opening of the aromatic ring to common metabolites. The hybrid phenylacetate degradation pathway is encoded in Escherichia coli by the paa operon containing genes for 10 enzymes. Previously, we have analyzed protein-protein interactions among the enzymes catalyzing the initial oxidation steps in the paa pathway (Grishin, A. M., Ajamian, E., Tao, L., Zhang, L., Menard, R., and Cygler, M. (2011) J. Biol. Chem. 286, 10735-10743). Here we report characterization of interactions between the remaining enzymes of this pathway and show another stable complex, PaaFG, an enoyl-CoA hydratase and enoyl-Coa isomerase, both belonging to the crotonase superfamily. These steps are biochemically similar to the well studied fatty acid β-oxidation, which can be catalyzed by individual monofunctional enzymes, multifunctional enzymes comprising several domains, or enzymatic complexes such as the bacterial fatty acid β-oxidation complex. We have determined the structure of the PaaFG complex and determined that although individually PaaF and PaaG are similar to enzymes from the fatty acid β-oxidation pathway, the structure of the complex is dissimilar from bacterial fatty acid β-oxidation complexes. The PaaFG complex has a four-layered structure composed of homotrimeric discs of PaaF and PaaG. The active sites of PaaF and PaaG are adapted to accept the intermediary components of the Paa pathway, different from those of the fatty acid β-oxidation. The association of PaaF and PaaG into a stable complex might serve to speed up the steps of the pathway following the conversion of phenylacetyl-CoA to a toxic and unstable epoxide-CoA by PaaABCE monooxygenase.

PubMed: 22961985
DOI: 10.1074/jbc.M112.388231

Experimental method

X-RAY DIFFRACTION (2.55 Å)