PDBsum entry 4hep

Viral protein

PDB id: 4hep

Contents

Protein chains

162 a.a.

130 a.a.

Ligands

SO4

Waters ×325

PDB id:

4hep

Name:

Viral protein

Title:

Complex of lactococcal phage tp901-1 with a llama vhh (vhh17) binder (nanobody)

Structure:

Bpp. Chain: a. Synonym: baseplate protein. Engineered: yes. Vhh17 domain. Chain: g. Engineered: yes

Source:

Lactococcus phage tp901-1. Organism_taxid: 35345. Gene: bpp, orf49. Expressed in: escherichia coli. Expression_system_taxid: 562. Lama glama. Llama. Organism_taxid: 9844.

Resolution:

1.75Å R-factor: 0.198 R-free: 0.204

Authors:

A.Desmyter,S.Spinelli,C.Farenc,S.Blangy,C.Bebeacua,D.Van Sinderen, J.Mahony,C.Cambillau

Key ref:

A.Desmyter et al. (2013). Viral infection modulation and neutralization by camelid nanobodies. Proc Natl Acad Sci U S A, 110, E1371. PubMed id: 23530214 DOI: 10.1073/pnas.1301336110

Date:

04-Oct-12 Release date: 20-Mar-13

Protein chain

Q9G096  (Q9G096_9CAUD) -  BPP from Lactococcus phage TP901-1

Seq: 163 a.a.

Struc: 162 a.a.

Protein chain

No UniProt id for this chain

Struc: 130 a.a.

DOI no: 10.1073/pnas.1301336110

Proc Natl Acad Sci U S A 110:E1371 (2013)

PubMed id: 23530214

Viral infection modulation and neutralization by camelid nanobodies.

A.Desmyter, C.Farenc, J.Mahony, S.Spinelli, C.Bebeacua, S.Blangy, D.Veesler, D.van Sinderen, C.Cambillau.

ABSTRACT

Lactococcal phages belong to a large family of Siphoviridae and infect Lactococcus lactis, a gram-positive bacterium used in commercial dairy fermentations. These phages are believed to recognize and bind specifically to pellicle polysaccharides covering the entire bacterium. The phage TP901-1 baseplate, located at the tip of the tail, harbors 18 trimeric receptor binding proteins (RBPs) promoting adhesion to a specific lactococcal strain. Phage TP901-1 adhesion does not require major conformational changes or Ca(2+), which contrasts other lactococcal phages. Here, we produced and characterized llama nanobodies raised against the purified baseplate and the Tal protein of phage TP901-1 as tools to dissect the molecular determinants of phage TP901-1 infection. Using a set of complementary techniques, surface plasmon resonance, EM, and X-ray crystallography in a hybrid approach, we identified binders to the three components of the baseplate, analyzed their affinity for their targets, and determined their epitopes as well as their functional impact on TP901-1 phage infectivity. We determined the X-ray structures of three nanobodies in complex with the RBP. Two of them bind to the saccharide binding site of the RBP and are able to fully neutralize TP901-1 phage infectivity, even after 15 passages. These results provide clear evidence for a practical use of nanobodies in circumventing lactococcal phages viral infection in dairy fermentation.