PDBsum entry 1bmu

Hydrolase

PDB id: 1bmu

Contents

Protein chain

214 a.a.

Theoretical model

PDB id:

1bmu

Name:

Hydrolase

Title:

Molecular model of brugia pahangi third-stage larvae cysteine protease.

Structure:

Cathepsin l-like. Chain: a. Ec: 3.4.22.15

Source:

Brugia pahangi

Authors:

P.M.Selzer,X.Chen,F.E.Cohen,J.H.Mckerrow

Key ref:

N.J.Stonehouse et al. (1996). Crystal structures of MS2 capsids with mutations in the subunit FG loop. J Mol Biol, 256, 330-339. PubMed id: 8594200 DOI: 10.1006/jmbi.1996.0089

Date:

24-Jul-98 Release date: 29-Jul-98

Protein chain

O17473  (CATL_BRUPA) -  Cathepsin L-like

Seq: 395 a.a.

Struc: 214 a.a.*

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

DOI no: 10.1006/jmbi.1996.0089

J Mol Biol 256:330-339 (1996)

PubMed id: 8594200

Crystal structures of MS2 capsids with mutations in the subunit FG loop.

N.J.Stonehouse, K.Valegård, R.Golmohammadi, S.van den Worm, C.Walton, P.G.Stockley, L.Liljas.

ABSTRACT

The loop between the F and G beta strands (FG loop) of the bacteriophage MS2 coat protein subunit forms inter-subunit contacts around the 5-fold and 3-fold (quasi 6-fold) axes of the T=3 protein shell. In capsids, the loop is found in two very different conformations, one in B subunits, which form the 5-fold contact, and one in A and C subunits, which form the quasi 6-fold contact. One proline residue, Pro78, is strictly conserved in the coat protein of all related bacteriophages, and in the case of MS2 this proline residue is preceded by a cis peptide bond in the B subunit. In order to probe the role of the FG loop in capsid assembly, we have determined the crystal structures of two MS2 capsids, formed by coat proteins with mutations at two positions in the FG loop, P78N or E76D. These mutants show conformational changes in the FG loops that explain the reduced temperature stability of the capsids. The P78N mutant has a normal trans peptide bond at position 78.

Selected figure(s)

Figure 2.
Figure 2. Schematic drawing of six coat protein subunits. The three independent subunits A, B and C making up one asymmetric unit of the icosahedron are drawn with black lines, and the three subunits A', B' and C' completing the dimers are shown in grey. At the 3-fold and 5-fold axes, the FG loops of all interacting subunits are shown. The position of the 3-fold and 5-fold axes are each shown with a stick. A drawing of an icosahedron in the same orientation is shown (inset). The drawing was made using the program MOLSCRIPT (Kraulis, 1991).

The above figure is reprinted by permission from Elsevier: J Mol Biol (1996, 256, 330-339) copyright 1996.