PDBsum entry 1b7e

Transferase inhibitor

PDB id: 1b7e

Contents

Protein chain

372 a.a. *

Ligands

TPT ×2

Waters ×56

* Residue conservation analysis

PDB id:

1b7e

Name:

Transferase inhibitor

Title:

Transposase inhibitor

Structure:

Protein (transposase inhibitor protein from tn5). Chain: a. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 562. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

2.90Å R-factor: 0.195

Authors:

D.R.Davies,L.M.Braam,W.S.Reznikoff,I.Rayment

Key ref:

D.R.Davies et al. (1999). The three-dimensional structure of a Tn5 transposase-related protein determined to 2.9-A resolution. J Biol Chem, 274, 11904-11913. PubMed id: 10207011 DOI: 10.1074/jbc.274.17.11904

Date:

22-Jan-99 Release date: 21-Apr-99

Protein chain

Q46731  (TN5P_ECOLX) -  Transposase for transposon Tn5 from Escherichia coli

Seq: 476 a.a.

Struc: 372 a.a.

Enzyme reactions

• Enzyme class: E.C.3.1.-.-

DOI no: 10.1074/jbc.274.17.11904

J Biol Chem 274:11904-11913 (1999)

PubMed id: 10207011

The three-dimensional structure of a Tn5 transposase-related protein determined to 2.9-A resolution.

D.R.Davies, L.Mahnke Braam, W.S.Reznikoff, I.Rayment.

ABSTRACT

Transposon Tn5 employs a unique means of self-regulation by expressing a truncated version of the transposase enzyme that acts as an inhibitor. The inhibitor protein differs from the full-length transposase only by the absence of the first 55 N-terminal amino acid residues. It contains the catalytic active site of transposase and a C-terminal domain involved in protein-protein interactions. The three-dimensional structure of Tn5 inhibitor determined to 2.9-A resolution is reported here. A portion of the protein fold of the catalytic core domain is similar to the folds of human immunodeficiency virus-1 integrase, avian sarcoma virus integrase, and bacteriophage Mu transposase. The Tn5 inhibitor contains an insertion that extends the beta-sheet of the catalytic core from 5 to 9 strands. All three of the conserved residues that make up the "DDE" motif of the active site are visible in the structure. An arginine residue that is strictly conserved among the IS4 family of bacterial transposases is present at the center of the active site, suggesting a catalytic motif of "DDRE." A novel C-terminal domain forms a dimer interface across a crystallographic 2-fold axis. Although this dimer represents the structure of the inhibited complex, it provides insight into the structure of the synaptic complex.

Selected figure(s)

Figure 2.
Fig. 2. Stereo ribbon diagram of Tn5 inhibitor protein. Figs. 2-5 were prepared with the program MOLSCRIPT (70).

Figure 3.
Fig. 3. Ribbon representation of the dimer viewed perpendicular to the 2-fold axis (a) and along the crystallographic 2-fold axis (b). The color scheme is as follows: blue, the structurally conserved catalytic core amino acid residues Ser^70-Leu^224, Leu^309-Gln^365; yellow, -sheet insertion, Leu^224-Leu^309; red, C-terminal dimerization domain, Leu^366-Gln^472. The active site residues, Asp^97, Asp^188, Arg^322, and Glu^326, are included in ball-and-stick representation.

The above figures are reprinted by permission from the ASBMB: J Biol Chem (1999, 274, 11904-11913) copyright 1999.

Figures were selected by an automated process.