PDBsum entry 4hic

Unknown function

PDB id: 4hic

Contents

Protein chains

204 a.a.

PDB id:

4hic

Name:

Unknown function

Title:

Crystal structure of the potential transfer protein trak from gram- positive conjugative plasmid pip501

Structure:

Trak. Chain: a, b. Engineered: yes

Source:

Enterococcus faecalis. Organism_taxid: 1351. Gene: orf11 from conjugative plasmid pip501. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

3.00Å R-factor: 0.213 R-free: 0.234

Authors:

N.Goessweiner-Mohr,W.Keller

Key ref:

N.Goessweiner-Mohr et al. (2014). The type IV secretion protein TraK from the Enterococcus conjugative plasmid pIP501 exhibits a novel fold. Acta Crystallogr D Biol Crystallogr, 70, 1124-1135. PubMed id: 24699656 DOI: 10.1107/S1399004714001606

Date:

11-Oct-12 Release date: 22-Jan-14

Protein chains

Q8L1C9  (Q8L1C9_ENTFL) -  Sigma from Enterococcus faecalis

Seq: 307 a.a.

Struc: 204 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1107/S1399004714001606

Acta Crystallogr D Biol Crystallogr 70:1124-1135 (2014)

PubMed id: 24699656

The type IV secretion protein TraK from the Enterococcus conjugative plasmid pIP501 exhibits a novel fold.

N.Goessweiner-Mohr, C.Fercher, K.Arends, R.Birner-Gruenberger, D.Laverde-Gomez, J.Huebner, E.Grohmann, W.Keller.

ABSTRACT

Conjugative plasmid transfer presents a serious threat to human health as the most important means of spreading antibiotic resistance and virulence genes among bacteria. The required direct cell-cell contact is established by a multi-protein complex, the conjugative type IV secretion system (T4SS). The conjugative core complex spans the cellular envelope and serves as a channel for macromolecular secretion. T4SSs of Gram-negative (G-) origin have been studied in great detail. In contrast, T4SSs of Gram-positive (G+) bacteria have only received little attention thus far, despite the medical relevance of numerous G+ pathogens (e.g. enterococci, staphylococci and streptococci). This study provides structural information on the type IV secretion (T4S) protein TraK of the G+ broad host range Enterococcus conjugative plasmid pIP501. The crystal structure of the N-terminally truncated construct TraKΔ was determined to 3.0 Å resolution and exhibits a novel fold. Immunolocalization demonstrated that the protein localizes to the cell wall facing towards the cell exterior, but does not exhibit surface accessibility. Circular dichroism, dynamic light scattering and size-exclusion chromatography confirmed the protein to be a monomer. With the exception of proteins from closely related T4SSs, no significant sequence or structural relatives were found. This observation marks the protein as a very exclusive, specialized member of the pIP501 T4SS.