6BSN
Structure of proline utilization A (PutA) with proline bound in remote sites
Summary for 6BSN
| Entry DOI | 10.2210/pdb6bsn/pdb |
| Descriptor | Bifunctional protein PutA, DIHYDROFLAVINE-ADENINE DINUCLEOTIDE, PROLINE, ... (5 entities in total) |
| Functional Keywords | flavoenzyme, rossmann fold, aldehyde dehydrogenase, flavin adenine dinucleotide, nicotinamide adenine dinucleotide, proline catabolism, substrate channeling, bifunctional enzyme, oxidoreductase |
| Biological source | Bradyrhizobium diazoefficiens (strain JCM 10833 / IAM 13628 / NBRC 14792 / USDA 110) |
| Total number of polymer chains | 2 |
| Total formula weight | 219287.75 |
| Authors | Tanner, J.J.,Korasick, D.A. (deposition date: 2017-12-04, release date: 2018-01-03, Last modification date: 2023-10-04) |
| Primary citation | Korasick, D.A.,Pemberton, T.A.,Arentson, B.W.,Becker, D.F.,Tanner, J.J. Structural Basis for the Substrate Inhibition of Proline Utilization A by Proline. Molecules, 23:-, 2017 Cited by PubMed Abstract: Proline utilization A (PutA) is a bifunctional flavoenzyme that catalyzes the two-step oxidation of l-proline to l-glutamate using spatially separated proline dehydrogenase (PRODH) and l-glutamate-γ-semialdehyde dehydrogenase (GSALDH) active sites. Substrate inhibition of the coupled PRODH-GSALDH reaction by proline is a common kinetic feature of PutAs, yet the structural basis for this phenomenon remains unknown. To understand the mechanism of substrate inhibition, we determined the 2.15 Å resolution crystal structure of PutA complexed with proline. Proline was discovered in five locations remote from the PRODH active site. Most notably, strong electron density indicated that proline bound tightly to the GSAL binding site of the GSALDH active site. The pose and interactions of proline bound in this site are remarkably similar to those of the natural aldehyde substrate, GSAL, implying that proline inhibits the GSALDH reaction of PutA. Kinetic measurements show that proline is a competitive inhibitor of the PutA GSALDH reaction. Together, the structural and kinetic data show that substrate inhibition of the PutA coupled reaction is due to proline binding in the GSAL site. PubMed: 29295473DOI: 10.3390/molecules23010032 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.15 Å) |
Structure validation
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