PDBsum entry 4os4

Hydrolase/hydrolase inhibitor

PDB id: 4os4

Contents

Protein chains

245 a.a.

15 a.a.

Ligands

SO4 ×2

GOL

ACT

Metals

_CL

Waters ×197

PDB id:

4os4

Name:

Hydrolase/hydrolase inhibitor

Title:

Crystal structure of urokinase-type plasminogen activator (upa) complexed with bicyclic peptide uk603 (bicyclic 1)

Structure:

Urokinase-type plasminogen activator. Chain: a. Fragment: catalytic domain (unp residues 179-423). Synonym: u-plasminogen activator, upa, urokinase-type plasminogen activator long chain a, urokinase-type plasminogen activator short chain a, urokinase-type plasminogen activator chain b. Engineered: yes. Mutation: yes. Bicyclic peptide uk603 (bicyclic 1).

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: plau. Expressed in: homo sapiens. Expression_system_taxid: 9606. Expression_system_cell_line: hek293. Synthetic: yes

Resolution:

2.00Å R-factor: 0.167 R-free: 0.214

Authors:

S.Chen,F.Pojer,C.Heinis

Key ref:

S.Chen et al. (2014). Dithiol amino acids can structurally shape and enhance the ligand-binding properties of polypeptides. Nat Chem, 6, 1009-1016. PubMed id: 25343607 DOI: 10.1038/nchem.2043

Date:

12-Feb-14 Release date: 24-Sep-14

Protein chain

P00749  (UROK_HUMAN) -  Urokinase-type plasminogen activator from Homo sapiens

Seq: 431 a.a.

Struc: 245 a.a.*

Protein chain

No UniProt id for this chain

Struc: 15 a.a.

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

Enzyme reactions

• Enzyme class: Chain A: E.C.3.4.21.73 - u-plasminogen activator.
• Reaction: Specific cleavage of Arg-|-Val bond in plasminogen to form plasmin.

DOI no: 10.1038/nchem.2043

Nat Chem 6:1009-1016 (2014)

PubMed id: 25343607

Dithiol amino acids can structurally shape and enhance the ligand-binding properties of polypeptides.

S.Chen, R.Gopalakrishnan, T.Schaer, F.Marger, R.Hovius, D.Bertrand, F.Pojer, C.Heinis.

ABSTRACT

The disulfide bonds that form between two cysteine residues are important in defining and rigidifying the structures of proteins and peptides. In polypeptides containing multiple cysteine residues, disulfide isomerization can lead to multiple products with different biological activities. Here, we describe the development of a dithiol amino acid (Dtaa) that can form two disulfide bridges at a single amino acid site. Application of Dtaas to a serine protease inhibitor and a nicotinic acetylcholine receptor inhibitor that contain disulfide constraints enhanced their inhibitory activities 40- and 7.6-fold, respectively. X-ray crystallographic and NMR structure analysis show that the peptide ligands containing Dtaas have retained their native tertiary structures. We furthermore show that replacement of two cysteines by Dtaas can avoid the formation of disulfide bond isomers. With these properties, Dtaas are likely to have broad application in the rational design or directed evolution of peptides and proteins with high activity and stability.