1DUV
CRYSTAL STRUCTURE OF E. COLI ORNITHINE TRANSCARBAMOYLASE COMPLEXED WITH NDELTA-L-ORNITHINE-DIAMINOPHOSPHINYL-N-SULPHONIC ACID (PSORN)
Summary for 1DUV
Entry DOI | 10.2210/pdb1duv/pdb |
Related | 1OTH 2OTC |
Descriptor | ORNITHINE TRANSCARBAMOYLASE, NDELTA-(N'-SULPHODIAMINOPHOSPHINYL)-L-ORNITHINE, (4S)-2-METHYL-2,4-PENTANEDIOL, ... (4 entities in total) |
Functional Keywords | enzyme-inhibitor complex, transferase |
Biological source | Escherichia coli |
Cellular location | Cytoplasm (Probable): P04391 |
Total number of polymer chains | 3 |
Total formula weight | 111445.40 |
Authors | Langley, D.B.,Templeton, M.D.,Fields, B.A.,Mitchell, R.E.,Collyer, C.A. (deposition date: 2000-01-18, release date: 2000-07-04, Last modification date: 2024-02-07) |
Primary citation | Langley, D.B.,Templeton, M.D.,Fields, B.A.,Mitchell, R.E.,Collyer, C.A. Mechanism of inactivation of ornithine transcarbamoylase by Ndelta -(N'-Sulfodiaminophosphinyl)-L-ornithine, a true transition state analogue? Crystal structure and implications for catalytic mechanism. J.Biol.Chem., 275:20012-20019, 2000 Cited by PubMed Abstract: The crystal structure is reported at 1.8 A resolution of Escherichia coli ornithine transcarbamoylase in complex with the active derivative of phaseolotoxin from Pseudomonas syringae pv. phaseolicola, N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine. Electron density reveals that the complex is not a covalent adduct as previously thought. Kinetic data confirm that N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine exhibits reversible inhibition with a half-life in the order of approximately 22 h and a dissociation constant of K(D) = 1.6 x 10(-12) m at 37 degrees C and pH 8.0. Observed hydrogen bonding about the chiral tetrahedral phosphorus of the inhibitor is consistent only with the presence of the R enantiomer. A strong interaction is also observed between Arg(57) Nepsilon and the P-N-S bridging nitrogen indicating that imino tautomers of N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine are present in the bound state. An imino tautomer of N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine is structurally analogous to the proposed reaction transition state. Hence, we propose that N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine, with its three unique N-P bonds, represents a true transition state analogue for ornithine transcarbamoylases, consistent with the tight binding kinetics observed. PubMed: 10747936DOI: 10.1074/jbc.M000585200 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (1.7 Å) |
Structure validation
Download full validation report