Structural highlights
1tj2 is a 1 chain structure with sequence from "bacillus_coli"_migula_1895 "bacillus coli" migula 1895. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| Ligands: | , |
| Related: | 1tiw, 1tj0, 1k87, 1tj1 |
| Gene: | PUTA, POAA, B1014 ("Bacillus coli" Migula 1895) |
| Activity: | Proline dehydrogenase, with EC number 1.5.99.8 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum |
Function
[PUTA_ECOLI] Oxidizes proline to glutamate for use as a carbon and nitrogen source and also function as a transcriptional repressor of the put operon.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Proline dehydrogenase (PRODH) catalyzes the first step of proline catabolism, the flavin-dependent oxidation of proline to Delta(1)-pyrroline-5-carboxylate. Here we present a structure-based study of the PRODH active site of the multifunctional Escherichia coli proline utilization A (PutA) protein using X-ray crystallography, enzyme kinetic measurements, and site-directed mutagenesis. Structures of the PutA PRODH domain complexed with competitive inhibitors acetate (K(i) = 30 mM), L-lactate (K(i) = 1 mM), and L-tetrahydro-2-furoic acid (L-THFA, K(i) = 0.2 mM) have been determined to high-resolution limits of 2.1-2.0 A. The discovery of acetate as a competitive inhibitor suggests that the carboxyl is the minimum functional group recognized by the active site, and the structures show how the enzyme exploits hydrogen-bonding and nonpolar interactions to optimize affinity for the substrate. The PRODH/L-THFA complex is the first structure of PRODH with a five-membered ring proline analogue bound in the active site and thus provides new insights into substrate recognition and the catalytic mechanism. The ring of L-THFA is nearly parallel to the middle ring of the FAD isoalloxazine, with the inhibitor C5 atom 3.3 A from the FAD N5. This geometry suggests direct hydride transfer as a plausible mechanism. Mutation of conserved active site residue Leu432 to Pro caused a 5-fold decrease in k(cat) and a severe loss in thermostability. These changes are consistent with the location of Leu432 in the hydrophobic core near residues that directly contact FAD. Our results suggest that the molecular basis for increased plasma proline levels in schizophrenic subjects carrying the missense mutation L441P is due to decreased stability of human PRODH2.
Structures of the Escherichia coli PutA proline dehydrogenase domain in complex with competitive inhibitors.,Zhang M, White TA, Schuermann JP, Baban BA, Becker DF, Tanner JJ Biochemistry. 2004 Oct 5;43(39):12539-48. PMID:15449943[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Zhang M, White TA, Schuermann JP, Baban BA, Becker DF, Tanner JJ. Structures of the Escherichia coli PutA proline dehydrogenase domain in complex with competitive inhibitors. Biochemistry. 2004 Oct 5;43(39):12539-48. PMID:15449943 doi:http://dx.doi.org/10.1021/bi048737e
