Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - AB 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 28284.19 
• Atom Count: 1969 
• Residue Count: 269 
• Unique protein chains: 2

1LDT

COMPLEX OF LEECH-DERIVED TRYPTASE INHIBITOR WITH PORCINE TRYPSIN

• DOI: 10.2210/pdb1LDT/pdb

• Classification: COMPLEX (HYDROLASE/INHIBITOR)
• Organism(s): Hirudo medicinalis, Sus scrofa
• Expression System: Saccharomyces cerevisiae


• Deposited: 1997-05-15 Released: 1998-05-20 
• Deposition Author(s): Stubbs, M.T.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.9 Å
• R-Value Work: 0.197 

Literature

The three-dimensional structure of recombinant leech-derived tryptase inhibitor in complex with trypsin. Implications for the structure of human mast cell tryptase and its inhibition.

Stubbs, M.T., Morenweiser, R., Sturzebecher, J., Bauer, M., Bode, W., Huber, R., Piechottka, G.P., Matschiner, G., Sommerhoff, C.P., Fritz, H., Auerswald, E.A.

(1997) J.Biol.Chem. 272: 19931-19937

• PubMed: 9242660 


• PubMed Abstract: 
  

The x-ray crystal structure of recombinant leech-derived tryptase inhibitor (rLDTI) has been solved to a resolution of 1.9 A in complex with porcine trypsin. The nonclassical Kazal-type inhibitor exhibits the same overall architecture as that observed in solution and in rhodniin. The complex reveals structural aspects of the mast cell proteinase tryptase. The conformation of the binding region of rLDTI suggests that tryptase has a restricted active site cleft. The basic amino terminus of rLDTI, apparently flexible from previous NMR measurements, approaches the 148-loop of trypsin. This loop has an acidic equivalent in tryptase, suggesting that the basic amino terminus could make favorable electrostatic interactions with the tryptase molecule. A series of rLDTI variants constructed to probe this hypothesis confirmed that the amino-terminal Lys-Lys sequence plays a role in inhibition of human lung tryptase but not of trypsin or chymotrypsin. The location of such an acidic surface patch is in accordance with the known low molecular weight inhibitors of tryptase.

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Related Citations: 

• Recombinant Leech-Derived Tryptase Inhibitor: Construction, Production, Protein Chemical Characterization and Inhibition of HIV-1 Replication
  Auerswald, E.A.,Morenweiser, R.,Sommerhoff, C.P.,Piechottka, G.P.,Eckerskorn, C.,Gurtler, L.G.,Fritz, H.
  (1994) Biol.Chem.Hoppe-Seyler 375: 695
• A Kazal-Type Inhibitor of Human Mast Cell Tryptase: Isolation from the Medical Leech Hirudo Medicinalis, Characterization, and Sequence Analysis
  Sommerhoff, C.P.,Sollner, C.,Mentele, R.,Piechottka, G.P.,Auerswald, E.A.,Fritz, H.
  (1994) Biol.Chem.Hoppe-Seyler 375: 685
• Structure of Leech Derived Tryptase Inhibitor (Ldti-C) in Solution
  Muhlhahn, P.,Czisch, M.,Morenweiser, R.,Habermann, B.,Engh, R.A.,Sommerhoff, C.P.,Auerswald, E.A.,Holak, T.A.
  (1994) FEBS Lett. 355: 290




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Organizational Affiliation: 

Max-Planck-Institut für Biochemie, Am Klopferspitz, D-82152 Martinsried bei München, Germany.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
TRYPSIN	T	223	Sus scrofa	Mutation(s): 0  EC: 3.4.21.4
Find proteins for P00761 (Sus scrofa) Go to UniProtKB:  P00761

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
TRYPTASE INHIBITOR	L	46	Hirudo medicinalis	Mutation(s): 0
Find proteins for P80424 (Hirudo medicinalis) Go to UniProtKB:  P80424

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
CA	T	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.9 Å
• R-Value Work: 0.197 
• Space Group: P 4₃ 2₁ 2

Unit Cell:

Length (Å)	Angle (°)
a = 63.400	α = 90.00
b = 63.400	β = 90.00
c = 131.200	γ = 90.00

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
MOSFLM	data reduction
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1997-05-15 
• Released Date: 1998-05-20 
• Deposition Author(s): Stubbs, M.T.

Revision History 

• Version 1.0: 1998-05-20
  Type: Initial release
• Version 1.1: 2008-03-24
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance