title: Oligopeptidase B from L. amazonensis: molecular cloning, gene expression analysis and molecular model.
abstract: Serine oligopeptidases of trypanosomatids are emerging as important virulence factors and therapeutic targets in trypanosome infections. A complete open reading frame of oligopeptidase B from Leishmania amazonensis was amplified with polymerase chain reaction with gradient annealing temperatures using primers designed for the oligopeptidase B gene from L. major. The 2,196-bp fragment coded for a protein of 731 amino acids with a predicted molecular mass of 83.49 KDa. The encoded protein (La_OpB) shares a 90% identity with oligopeptidases of L. major and L. infantum, 84% with L. braziliensis, and approximately 62 identity with Trypanosoma peptidases. The oligopeptidase B gene is expressed in all cycle stages of L. amazonensis. The three dimensional model of La_OpB was obtained by homology modeling based on the structure of prolyl oligopeptidases. We mapped a La_OpB model that presents a greater negative charge than prolyl oligopeptidases; our results suggest a difference in the S2 subsite when compared to oligopeptidases B from Trypanosoma and bacterial oligopeptidases B. The La_OpB model serves as a starting point for its exploration as a potential target source for a rational chemotherapy.
authors.affiliation: Laboratório de Bioquímica de Proteínas e Peptídeos, Departamento de Bioquímica e Biologia Molecular, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
authors.forename: Herbert Leonel
authors.initials: HL
authors.lastname: de Matos Guedes
authors.forename: Monique Pacheco Duarte
authors.initials: MP
authors.lastname: Carneiro
authors.forename: Daniel Cláudio de Oliveira
authors.initials: DC
authors.lastname: Gomes
authors.forename: Bartira
authors.initials: B
authors.lastname: Rossi-Bergmanmn
authors.forename: Salvatore
authors.initials: S
authors.lastname: Giovanni de Simone
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D005786:Gene Expression Regulation; D007891:Leishmania / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D012697:Serine Endopeptidases; C090703:oligopeptidase B