PDBsum entry 2dfy

Transcription

PDB id: 2dfy

Contents

Protein chains

158 a.a. *

Ligands

GOL ×2

Metals

_ZN ×8

Waters ×244

* Residue conservation analysis

PDB id:

2dfy

Name:

Transcription

Title:

Crystal structure of a cyclized protein fusion of lmo4 lim domains 1 and 2 with the lim interacting domain of ldb1

Structure:

Fusion protein of lim domain transcription factor lmo4 and lim domain-binding protein 1. Chain: x, c. Fragment: lmo4. Synonym: cz-flinc4. Engineered: yes. Mutation: yes. Other_details: cyclised fusion of lmo4 residues 18-152 to ldb1 lid residues 300-339 via two flexible linkers with sequence ggsggsggsgg

Source:

Mus musculus. House mouse. Organism_taxid: 10090. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

1.65Å R-factor: 0.168 R-free: 0.194

Authors:

C.M.J.Jeffries,S.C.Graham,C.A.Collyer,J.M.Guss,J.M.Matthews

Key ref:

C.M.Jeffries et al. (2006). Stabilization of a binary protein complex by intein-mediated cyclization. Protein Sci, 15, 2612-2618. PubMed id: 17001033 DOI: 10.1110/ps.062377006

Date:

06-Mar-06 Release date: 31-Oct-06

Protein chains

P61969  (LMO4_MOUSE) -  LIM domain transcription factor LMO4 from Mus musculus

Seq: 165 a.a.

Struc: 158 a.a.*

* PDB and UniProt seqs differ at 19 residue positions (black crosses)

DOI no: 10.1110/ps.062377006

Protein Sci 15:2612-2618 (2006)

PubMed id: 17001033

Stabilization of a binary protein complex by intein-mediated cyclization.

C.M.Jeffries, S.C.Graham, P.H.Stokes, C.A.Collyer, J.M.Guss, J.M.Matthews.

ABSTRACT

The study of protein-protein interactions can be hampered by the instability of one or more of the protein complex components. In this study, we showed that intein-mediated cyclization can be used to engineer an artificial intramolecular cyclic protein complex between two interacting proteins: the largely unstable LIM-only protein 4 (LMO4) and an unstructured domain of LIM domain binding protein 1 (ldb1). The X-ray structure of the cyclic complex is identical to noncyclized versions of the complex. Chemical and thermal denaturation assays using intrinsic tryptophan fluorescence and dynamic light scattering were used to compare the relative stabilities of the cyclized complex, the intermolecular (or free) complex, and two linear versions of the intramolecular complex (in which the interacting domains of LMO4 and ldb1 were fused, via a flexible linker, in either orientation). In terms of resistance to denaturation, the cyclic complex is the most stable variant and the intermolecular complex is the least stable; however, the two linear intramolecular variants show significant differences in stability. These differences appear to be related to the relative contact order (the average distance in sequence between residues that make contacts within a structure) of key binding residues at the interface of the two proteins. Thus, the restriction of the more stable component of a complex may enhance stability to a greater extent than restraining less stable components.

Selected figure(s)

Figure 1.
Figure 1. Proposed intein-mediated in vivo protein cyclization mechanism. A target gene is cloned between the C- and N-terminal

Figure 5.
Figure 5. cz-FLINC4 and FLINC4 are essentially identical. Structural alignment of cz-FLINC4 chain X (blue) and FLINC4 (green):

The above figures are reprinted by permission from the Protein Society: Protein Sci (2006, 15, 2612-2618) copyright 2006.

Figures were selected by the author.