PDBsum entry 2pns

Hydrolase

PDB id: 2pns

Contents

Protein chains

208 a.a. *

Ligands

PO4

THJ ×2

Waters ×260

* Residue conservation analysis

PDB id:

2pns

Name:

Hydrolase

Title:

1.9 angstrom resolution crystal structure of a plant cysteine protease ervatamin-c refinement with cdna derived amino acid sequence

Structure:

Ervatamin-c, a papain-like plant cysteine protease. Chain: a, b. Ec: 3.4.22.-

Source:

Tabernaemontana divaricata. Organism_taxid: 52861. Other_details: tropical flowering plant

Resolution:

1.90Å R-factor: 0.173 R-free: 0.193

Authors:

R.Ghosh,P.Guha Thakurta,S.Biswas,C.Chakrabarti,J.K.Dattagupta

Key ref:

R.Ghosh et al. (2007). A thermostable cysteine protease precursor from a tropical plant contains an unusual C-terminal propeptide: cDNA cloning, sequence comparison and molecular modeling studies. Biochem Biophys Res Commun, 362, 965-970. PubMed id: 17767923

Date:

25-Apr-07 Release date: 19-Jun-07

Protein chains

P83654  (ERVC1_TABDI) -  Ervatamin-C (Fragment) from Tabernaemontana divaricata

Seq: 208 a.a.

Struc: 208 a.a.*

* PDB and UniProt seqs differ at 25 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.3.4.22.- - ?????

Biochem Biophys Res Commun 362:965-970 (2007)

PubMed id: 17767923

A thermostable cysteine protease precursor from a tropical plant contains an unusual C-terminal propeptide: cDNA cloning, sequence comparison and molecular modeling studies.

R.Ghosh, J.K.Dattagupta, S.Biswas.

ABSTRACT

We report here the cloning and characterization of the entire cDNA of a papain-like cysteine protease from a tropical flowering plant. The 1098-bp ORF of the cDNA codify a protease precursor having a signal peptide of 19 amino acids, a cathepsin-L like N-terminal proregion of 114 amino acids, a mature enzyme part of 208 amino acids and a C-terminal proregion of 24 amino acids. The derived amino acid sequence of the mature part tallies with the thermostable cysteine protease Ervatamin-C--as was aimed at. The C-terminal proregion of the protease has altogether a different sequence pattern not observed in other members of the family and it contains a negatively charged helical zone. The three-dimensional model of the precursor, based on the homology modeling and X-ray structure, shows that the extended peptide stretch region of the N-terminal propeptide, covering the interdomain cleft, contains protruding side chains of positively charged residues. This study also indicates that the negatively charged zone of C-terminal propeptide may interact with the positively charged zone of the N-terminal propeptide in a cooperative manner in the maturation process of this enzyme.