3V7I
Germicidin synthase (Gcs) from Streptomyces coelicolor, a type III polyketide synthase
Summary for 3V7I
| Entry DOI | 10.2210/pdb3v7i/pdb |
| Descriptor | Putative polyketide synthase (2 entities in total) |
| Functional Keywords | type iii polyketide synthase, acyltransferase, transferase, lyase |
| Biological source | Streptomyces coelicolor |
| Total number of polymer chains | 1 |
| Total formula weight | 44488.84 |
| Authors | Akey, D.L.,Smith, J.L.,Geders, T.W. (deposition date: 2011-12-21, release date: 2012-04-18, Last modification date: 2024-02-28) |
| Primary citation | Chemler, J.A.,Buchholz, T.J.,Geders, T.W.,Akey, D.L.,Rath, C.M.,Chlipala, G.E.,Smith, J.L.,Sherman, D.H. Biochemical and Structural Characterization of Germicidin Synthase: Analysis of a Type III Polyketide Synthase That Employs Acyl-ACP as a Starter Unit Donor. J.Am.Chem.Soc., 134:7359-7366, 2012 Cited by PubMed Abstract: Germicidin synthase (Gcs) from Streptomyces coelicolor is a type III polyketide synthase (PKS) with broad substrate flexibility for acyl groups linked through a thioester bond to either coenzyme A (CoA) or acyl carrier protein (ACP). Germicidin synthesis was reconstituted in vitro by coupling Gcs with fatty acid biosynthesis. Since Gcs has broad substrate flexibility, we directly compared the kinetic properties of Gcs with both acyl-ACP and acyl-CoA. The catalytic efficiency of Gcs for acyl-ACP was 10-fold higher than for acyl-CoA, suggesting a strong preference toward carrier protein starter unit transfer. The 2.9 Å germicidin synthase crystal structure revealed canonical type III PKS architecture along with an unusual helical bundle of unknown function that appears to extend the dimerization interface. A pair of arginine residues adjacent to the active site affect catalytic activity but not ACP binding. This investigation provides new and surprising information about the interactions between type III PKSs and ACPs that will facilitate the construction of engineered systems for production of novel polyketides. PubMed: 22480290DOI: 10.1021/ja2112228 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.9 Å) |
Structure validation
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