title: Functional and immunological evaluation of two novel proteins of Leptospira spp.
abstract: This work shows the production and characterization of two novel putative lipoproteins encoded by the genes LIC10645 and LIC10731 identified in the genome sequences of Leptospira interrogans. In silico conservation analysis indicated that the proteins are well conserved among pathogenic leptospiral serovars and species. Recombinant proteins were obtained in Escherichia coli BL21(DE3) Star pLysS strain, purified by metal-affinity chromatography, and used for characterization and immunological evaluations. Recombinant proteins were capable of eliciting a combination of humoral and cellular immune responses in animal models, and could be recognized by antibodies present in human serum samples. The recombinant proteins Lsa44 and Lsa45 were able to bind laminin, and were named Lsa44 and Lsa45 for leptospiral surface adhesins of 44 and 45 kDa, respectively. The attachment to laminin was dose-responsive with KD values of 108.21 and 250.38 nM for Lsa44 and Lsa45, respectively. Moreover, these proteins interact with plasminogen (PLG) with KD values of 53.56 and 36.80 nM, respectively. PLG bound to the recombinant proteins could be converted to plasmin (PLA) in the presence of an activator. Cellular localization assays suggested that the Lsa44 and Lsa45 were surface-exposed. These are versatile proteins capable of interacting with laminin and PLG/PLA, and hence could mediate bacterial adhesion and contribute to tissue penetration.
authors.affiliation: Interunidades em Biotecnologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil.|Centro de Biotecnologia, Instituto Butantan, Avenida Vital Brazil 1500, 05503-900 São Paulo, SP, Brazil.
authors.forename: Luis G V
authors.initials: LGV
authors.lastname: Fernandes
authors.affiliation: Interunidades em Biotecnologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil.|Centro de Biotecnologia, Instituto Butantan, Avenida Vital Brazil 1500, 05503-900 São Paulo, SP, Brazil.
authors.forename: Monica L
authors.initials: ML
authors.lastname: Vieira
authors.affiliation: Centro de Biotecnologia, Instituto Butantan, Avenida Vital Brazil 1500, 05503-900 São Paulo, SP, Brazil.
authors.forename: Ivy J
authors.initials: IJ
authors.lastname: Alves
authors.affiliation: Laboratório de Zoonoses Bacterianas do VPS, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Zenaide M
authors.initials: ZM
authors.lastname: de Morais
authors.affiliation: Laboratório de Zoonoses Bacterianas do VPS, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Silvio A
authors.initials: SA
authors.lastname: Vasconcellos
authors.affiliation: Divisão de Biologia Medica, Instituto Adolfo Lutz, São Paulo, Brazil.
authors.forename: Eliete C
authors.initials: EC
authors.lastname: Romero
authors.affiliation: Centro de Biotecnologia, Instituto Butantan, Avenida Vital Brazil 1500, 05503-900 São Paulo, SP, Brazil.
authors.forename: Ana L T O
authors.initials: ALTO
authors.lastname: Nascimento
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D002846:Chromatography, Affinity; D017124:Conserved Sequence; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D007700:Kinetics; D007797:Laminin / Q000378:metabolism*; D007921:Leptospira interrogans / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008074:Lipoproteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D010958:Plasminogen / Q000378:metabolism; D011485:Protein Binding; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification
chemical_list: D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D007797:Laminin; D008074:Lipoproteins; D008565:Membrane Proteins; D011994:Recombinant Proteins; D010958:Plasminogen