PDBsum entry 5kb2

De novo protein

PDB id: 5kb2

Contents

Protein chain

36 a.a.

Metals

_ZN ×2

Waters ×35

PDB id:

5kb2

Name:

De novo protein

Title:

Crystal structure of a tris-thiolate zn(ii)s3o complex in a de novo three-stranded coiled coil peptide

Structure:

Zn(ii)(h2o)(grand coil ser-l12al16c)3-. Chain: a. Engineered: yes

Source:

Synthetic: yes. Synthetic construct. Organism_taxid: 32630

Resolution:

1.89Å R-factor: 0.207 R-free: 0.224

Authors:

L.Ruckthong,M.L.Zastrow,J.A.Stuckey,V.L.Pecoraro

Key ref:

L.Ruckthong et al. (2016). A Crystallographic Examination of Predisposition versus Preorganization in de Novo Designed Metalloproteins. J Am Chem Soc, 138, 11979-11988. PubMed id: 27532255 DOI: 10.1021/jacs.6b07165

Date:

02-Jun-16 Release date: 31-Aug-16

Protein chain

No UniProt id for this chain

Struc: 36 a.a.

DOI no: 10.1021/jacs.6b07165

J Am Chem Soc 138:11979-11988 (2016)

PubMed id: 27532255

A Crystallographic Examination of Predisposition versus Preorganization in de Novo Designed Metalloproteins.

L.Ruckthong, M.L.Zastrow, J.A.Stuckey, V.L.Pecoraro.

ABSTRACT

Preorganization and predisposition are important molecular recognition concepts exploited by nature to obtain site-specific and selective metal binding to proteins. While native structures containing an MS3 core are often unavailable in both apo- and holo-forms, one can use designed three-stranded coiled coils (3SCCs) containing tris-thiolate sites to evaluate these concepts. We show that the preferred metal geometry dictates the degree to which the cysteine rotamers change upon metal complexation. The Cys ligands in the apo-form are preorganized for binding trigonal pyramidal species (Pb(II)S3 and As(III)S3) in an endo conformation oriented toward the 3SCC C-termini, whereas the cysteines are predisposed for trigonal planar Hg(II)S3 and 4-coordinate Zn(II)S3O structures, requiring significant thiol rotation for metal binding. This study allows assessment of the importance of protein fold and side-chain reorientation for achieving metal selectivity in human retrotransposons and metalloregulatory proteins.