title: Engineering of a polymeric bacterial protein as a scaffold for the multiple display of peptides.
abstract: Protein assemblies with a high degree of repetitiveness and organization are known to induce strong immune responses. For that reason they have been postulated for the design of subunit vaccines by means of protein engineering. The enzyme lumazine synthase from Brucella spp. (BLS) is highly immunogenic, presumably owing to its homodecameric arrangement and remarkable thermodynamic stability. Structural analysis has shown that it is possible to insert foreign peptides at the ten amino terminus of BLS without disrupting its general folding. These peptides would be displayed to the immune system in a highly symmetric three-dimensional array. In the present work, BLS has been used as a protein carrier of foreign peptides. We have established a modular system to produce chimeric proteins decorated with ten copies of a desired peptide as long as 27 residues and have shown that their folding and stability is similar to that of the wild-type protein. The knowledge about the mechanisms of dissociation and unfolding of BLS allowed the engineering of polyvalent chimeras displaying different predefined peptides on the same molecular scaffold. Moreover, the reassembly of mixtures of chimeras at different steps of the unfolding process was used to control the stoichiometry and spatial arrangement for the simultaneous display of different peptides on BLS. This strategy would be useful for vaccine development and other biomedical applications.
authors.affiliation: Fundación Instituto Leloir, Consejo Nacional de Investigaciones Científicas y Técnicas and Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: D A
authors.initials: DA
authors.lastname: Laplagne
authors.forename: V
authors.initials: V
authors.lastname: Zylberman
authors.forename: N
authors.initials: N
authors.lastname: Ainciart
authors.forename: M W
authors.initials: MW
authors.lastname: Steward
authors.forename: E
authors.initials: E
authors.lastname: Sciutto
authors.forename: C A
authors.initials: CA
authors.lastname: Fossati
authors.forename: F A
authors.initials: FA
authors.lastname: Goldbaum
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D001704:Biopolymers / Q000737:chemistry / Q000378:metabolism; D002002:Brucella / Q000201:enzymology; D002942:Circular Dichroism; D015870:Gene Expression; D005822:Genetic Vectors; D051379:Mice; D008807:Mice, Inbred BALB C; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000737:chemistry / Q000235:genetics; D019151:Peptide Library; D015202:Protein Engineering; D017510:Protein Folding; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D001704:Biopolymers; D009097:Multienzyme Complexes; D019151:Peptide Library; D011993:Recombinant Fusion Proteins; C044822:6,7-dimethyl-8-ribityllumazine synthase