title: A Rhipicephalus (Boophilus) microplus cathepsin with dual peptidase and antimicrobial activity.
abstract: The cattle tick, Rhipicephalus (Boophilus) microplus, is a haematophagous arthropod responsible for considerable losses in the livestock industry. Immunological control with vaccines is a promising alternative to replace chemical acaricides. Due to their importance in parasite physiology, cysteine endopeptidases are potential targets. In a previous study, native Vitellin Degrading Cysteine Endopeptidase (VTDCE) was successfully tested as a vaccine antigen for bovines against R. microplus. In this work, nucleotide and amino acid VTDCE sequences were obtained from cDNA databanks, based on data from Edman sequencing and mass spectrometry. Subsequently, cloning and expression, purification, immunological and biochemical characterisation of the recombinant protein were performed to determine the biological importance of VTDCE. By Western blot, polyclonal antibodies produced against recombinant VTDCE recognised native VTDCE. Interestingly, molecular analysis showed that the VTDCE sequence has similarity to antimicrobial peptides. Indeed, experimental results revealed that VTDCE has an antimicrobial activity which is independent of endopeptidase activity. We believe that this is the first known study to show that an arthropod enzyme has antimicrobial activity.
authors.affiliation: Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Avenida Bento Gonçalves, 9500, Prédio 43421, Porto Alegre 91501-970, RS, Brazil.
authors.forename: Daiane P
authors.initials: DP
authors.lastname: Oldiges
authors.forename: Luís F
authors.initials: LF
authors.lastname: Parizi
authors.forename: Karine R
authors.initials: KR
authors.lastname: Zimmer
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Lorenzini
authors.forename: Adriana
authors.initials: A
authors.lastname: Seixas
authors.forename: Aoi
authors.initials: A
authors.lastname: Masuda
authors.forename: Itabajara
authors.initials: I
authors.lastname: da Silva Vaz
authors.forename: Carlos
authors.initials: C
authors.lastname: Termignoni
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000378:metabolism; D001483:Base Sequence; D002403:Cathepsins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D015870:Gene Expression; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010455:Peptides / Q000378:metabolism; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D048494:Rhipicephalus / Q000201:enzymology* / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein
chemical_list: D000890:Anti-Infective Agents; D018076:DNA, Complementary; D010455:Peptides; D011994:Recombinant Proteins; D002403:Cathepsins