English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/3081
Compartir / Impacto:
Add this article to your Mendeley library MendeleyBASE
Citado 58 veces en Web of Knowledge®  |  Pub MebCentral Ver citas en PubMed Central  |  Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar otros formatos: Exportar EndNote (RIS)Exportar EndNote (RIS)Exportar EndNote (RIS)
Título : Isolation, cloning and structural characterisation of boophilin, a multifunctional kunitz-type proteinase inhibitor from the cattle tick
Autor : Macedo-Ribeiro, Sandra; Almeida, Carla; Calisto, Barbara M.; Friedrich, Thomas; Mentele, Reinhard; Stürzebecher, Jörg; Fuentes-Prior, Pablo; Pereira, Pedro José Barbosa
Fecha de publicación : 20-feb-2008
Editor: Public Library of Science
Citación : 2008, PLoS ONE. 2008 Feb 20;3(2):e1624.
Resumen: Inhibitors of coagulation factors from blood-feeding animals display a wide variety of structural motifs and inhibition mechanisms. We have isolated a novel inhibitor from the cattle tick Boophilus microplus, one of the most widespread parasites of farm animals. The inhibitor, which we have termed boophilin, has been cloned and overexpressed in Escherichia coli. Mature boophilin is composed of two canonical Kunitz-type domains, and inhibits not only the major procoagulant enzyme, thrombin, but in addition, and by contrast to all other previously characterised natural thrombin inhibitors, significantly interferes with the proteolytic activity of other serine proteinases such as trypsin and plasmin. The crystal structure of the bovine alpha-thrombin.boophilin complex, refined at 2.35 A resolution reveals a non-canonical binding mode to the proteinase. The N-terminal region of the mature inhibitor, Q16-R17-N18, binds in a parallel manner across the active site of the proteinase, with the guanidinium group of R17 anchored in the S(1) pocket, while the C-terminal Kunitz domain is negatively charged and docks into the basic exosite I of thrombin. This binding mode resembles the previously characterised thrombin inhibitor, ornithodorin which, unlike boophilin, is composed of two distorted Kunitz modules. Unexpectedly, both boophilin domains adopt markedly different orientations when compared to those of ornithodorin, in its complex with thrombin. The N-terminal boophilin domain rotates 9 degrees and is displaced by 6 A, while the C-terminal domain rotates almost 6 degrees accompanied by a 3 A displacement. The reactive-site loop of the N-terminal Kunitz domain of boophilin with its P(1) residue, K31, is fully solvent exposed and could thus bind a second trypsin-like proteinase without sterical restraints. This finding explains the formation of a ternary thrombin.boophilin.trypsin complex, and suggests a mechanism for prothrombinase inhibition in vivo.
URI : http://hdl.handle.net/10261/3081
DOI: 10.1371/journal.pone.0001624
ISSN: 1932-6203
Aparece en las colecciones: (CIC) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
isolation.pdfMain text1,1 MBAdobe PDFVista previa
isolation_s001.tiffFigure S1. Mass spectrum of affinity-purified native boophilin obtained using MALDI-TOF.797,59 kBTIFFVista previa
isolation_s002.tiffFigure S2. Two-domain Kunitz inhibitors of thrombin display different surface potentials.3,12 MBTIFFVista previa
isolation_s003.docTable S1. Amino acid sequences of peptides derived from purified native boophilin.29 kBMicrosoft WordVisualizar/Abrir
isolation_s004.docTable S2. Oligonucleotides used for boophilin cloning.28 kBMicrosoft WordVisualizar/Abrir
Mostrar el registro completo

NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.