Experimental Data Snapshot
wwPDB Validation  3D Report Full Report
(1991) J Biological Chem 266: 20085-20093
The mode of binding of four active-site directed inhibitors to human thrombin has been determined by x-ray crystallographic analysis. The inhibitors studied are benzamidine, PPACK, NAPAP, and MD-805, of which the last three are compounds evolved specifically to inhibit thrombin. Crystal structures were determined in the presence of both the inhibitor and the undecapeptide [des-amino Asp55]hirudin(55-65) which binds distant from the active site. Despite having significantly different chemical structures, NAPAP and MD-805 bind to thrombin in a very similar "inhibitor binding mode" which is not that expected by direct analogy with the binding of substrate. Both inhibitors bind to thrombin in a similar way as to trypsin, but thrombin has an extra loop, the "Tyr-Pro-Pro-Trp loop," not present in trypsin, which gives further binding interactions and is seen to move somewhat to accommodate binding of the different inhibitors. The fact that NAPAP and MD-805 require different stereochemistry for potent inhibition is demonstrated, and its structural basis clarified. The wealth of data on analogs and variants of these lead compounds is shown to be compatible with this inhibitor binding mode.
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Biological assembly 1 assigned by authors and generated by PISA (software)
Macromolecule Content 
Entity ID: 1 | |||||
|---|---|---|---|---|---|
| Molecule | Chains | Sequence Length | Organism | Details | Image |
| ALPHA-THROMBIN (SMALL SUBUNIT) | A [auth L] | 36 | Homo sapiens | Mutation(s): 0  EC: 3.4.21.5 | ![]() |
UniProt & NIH Common Fund Data Resources | |||||
Find proteins for P00734 (Homo sapiens) Explore P00734  Go to UniProtKB:  P00734 | |||||
PHAROS:  P00734 GTEx:  ENSG00000180210  | |||||
Entity Groups  | |||||
| Sequence Clusters | 30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity | ||||
| UniProt Group | P00734 | ||||
Sequence AnnotationsExpand | |||||
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Entity ID: 2 | |||||
|---|---|---|---|---|---|
| Molecule | Chains | Sequence Length | Organism | Details | Image |
| ALPHA-THROMBIN (LARGE SUBUNIT) | B [auth H] | 259 | Homo sapiens | Mutation(s): 0  EC: 3.4.21.5 | ![]() |
UniProt & NIH Common Fund Data Resources | |||||
Find proteins for P00734 (Homo sapiens) Explore P00734  Go to UniProtKB:  P00734 | |||||
PHAROS:  P00734 GTEx:  ENSG00000180210  | |||||
Entity Groups  | |||||
| Sequence Clusters | 30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity | ||||
| UniProt Group | P00734 | ||||
Sequence AnnotationsExpand | |||||
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Find similar proteins by: Sequence | 3D Structure
Entity ID: 3 | |||||
|---|---|---|---|---|---|
| Molecule | Chains | Sequence Length | Organism | Details | Image |
| HIRUDIN IIIA | C [auth I] | 11 | Hirudo medicinalis | Mutation(s): 0  | ![]() |
UniProt | |||||
Find proteins for P28504 (Hirudo medicinalis) Explore P28504  Go to UniProtKB:  P28504 | |||||
Entity Groups  | |||||
| Sequence Clusters | 30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity | ||||
| UniProt Group | P28504 | ||||
Sequence AnnotationsExpand | |||||
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| Ligands 1 Unique | |||||
|---|---|---|---|---|---|
| ID | Chains | Name / Formula / InChI Key | 2D Diagram | 3D Interactions | |
| MID Query on MID Download Ideal Coordinates CCD File  | D [auth H] | 1-[N-(naphthalen-2-ylsulfonyl)glycyl-4-carbamimidoyl-D-phenylalanyl]piperidine C27 H31 N5 O4 S XXTWZTPVNIYSJZ-XMMPIXPASA-N | |||
Entity ID: 4 | |||||
|---|---|---|---|---|---|
| ID | Chains | Name | Type/Class | 2D Diagram | 3D Interactions |
| PRD_000451 (MID) Query on PRD_000451 | D [auth H] | N(alpha)-(2-naphthylsulfonylglycyl)-4-amidinophenylalanine piperidide | Peptide-like / Inhibitor | ||
| Length ( Å ) | Angle ( ˚ ) |
|---|---|
| a = 90.8 | α = 90 |
| b = 90.8 | β = 90 |
| c = 132.5 | γ = 90 |
| Software Name | Purpose |
|---|---|
| TNT | refinement |
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