PDBsum entry 4z3t

Protein binding

PDB id: 4z3t

Contents

Protein chains

249 a.a.

236 a.a.

Metals

_MG ×2

Waters ×377

PDB id:

4z3t

Name:

Protein binding

Title:

Meningococcal factor h binding protein mutant l130r/g133d

Structure:

Factor h binding protein variant a10_001. Chain: a, b. Fragment: unp residues 8-254. Synonym: lipoprotein,putative lipoprotein. Engineered: yes. Mutation: yes

Source:

Neisseria meningitidis. Organism_taxid: 487. Gene: fhbp. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

1.62Å R-factor: 0.195 R-free: 0.231

Authors:

M.Konar,P.T.Beernink

Key ref:

M.Konar et al. (2015). A meningococcal vaccine antigen engineered to increase thermal stability and stabilize protective epitopes. Proc Natl Acad Sci U S A, 112, 14823-14828. PubMed id: 26627237 DOI: 10.1073/pnas.1507829112

Date:

31-Mar-15 Release date: 04-Nov-15

Protein chain

Q6VS32  (Q6VS32_NEIME) -  Factor H binding protein variant A10_001 (Fragment) from Neisseria meningitidis

Seq: 254 a.a.

Struc: 249 a.a.*

Protein chain

Q6VS32  (Q6VS32_NEIME) -  Factor H binding protein variant A10_001 (Fragment) from Neisseria meningitidis

Seq: 254 a.a.

Struc: 236 a.a.*

* PDB and UniProt seqs differ at 5 residue positions (black crosses)

DOI no: 10.1073/pnas.1507829112

Proc Natl Acad Sci U S A 112:14823-14828 (2015)

PubMed id: 26627237

A meningococcal vaccine antigen engineered to increase thermal stability and stabilize protective epitopes.

M.Konar, R.Pajon, P.T.Beernink.

ABSTRACT

Factor H binding protein (FHbp) is part of two vaccines recently licensed for prevention of sepsis and meningitis caused by serogroup B meningococci. FHbp is classified in three phylogenic variant groups that have limited antigenic cross-reactivity, and FHbp variants in one of the groups have low thermal stability. In the present study, we replaced two amino acid residues, R130 and D133, in a stable FHbp variant with their counterparts (L and G) from a less stable variant. The single and double mutants decreased thermal stability of the amino- (N-) terminal domain compared with the wild-type protein as measured by scanning calorimetry. We introduced the converse substitutions, L130R and G133D, in a less stable wild-type FHbp variant, which increased the transition midpoint (Tm) for the N-terminal domain by 8 and 12 °C; together the substitutions increased the Tm by 21 °C. We determined the crystal structure of the double mutant FHbp to 1.6 Å resolution, which showed that R130 and D133 mediated multiple electrostatic interactions. Monoclonal antibodies specific for FHbp epitopes in the N-terminal domain had higher binding affinity for the recombinant double mutant by surface plasmon resonance and to the mutant expressed on meningococci by flow cytometry. The double mutant also had decreased binding of human complement Factor H, which in previous studies increased the protective antibody responses. The stabilized mutant FHbp thus has the potential to stabilize protective epitopes and increase the protective antibody responses to recombinant FHbp vaccines or native outer membrane vesicle vaccines with overexpressed FHbp.