A thrombin inhibitor from the ixodid tick, Amblyomma hebraeum.
A novel thrombin inhibitor named Amblin was identified from the haemolymph of the ixodid (hard) tick, Amblyomma hebraeum, and the coding cDNA was isolated from a tick cDNA library. This cDNA codes for a preprotein of 166 amino acids, including a predicted signal peptide composed of 15 amino acids N-terminal to the mature Amblin. The 151-amino-acid mature Amblin contains 14 cysteines and two Kunitz-like domains. It displays high sequence similarity with a tissue factor pathway inhibitor (TFPI), Ixolaris, from the ixodid tick, Ixodes scapularis, which has 10 cysteines, and a thrombin inhibitor, Boophilin, from the ixodid tick, Boophilus microplus, which has 12 cysteines. Recombinant Amblin specifically inhibited thrombin as efficiently as native Amblin did. This is the first report of a thrombin inhibitor from tick haemolymph.
Lai
Ren
R
Cell Regulation and Signalling Division, School of Biological Sciences, University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK.
Takeuchi
Hajime
H
Jonczy
Jan
J
Rees
Huw H
HH
Turner
Philip C
PC
D000595:Amino Acid Sequence; D000818:Animals; D000925:Anticoagulants / Q000097:blood / Q000494:pharmacology; D000991:Antithrombins / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology; D060829:Arthropod Proteins; D001483:Base Sequence; D001777:Blood Coagulation / Q000187:drug effects; D001798:Blood Proteins / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D006458:Hemolymph / Q000737:chemistry; D026863:Ixodidae / Q000235:genetics*; D008969:Molecular Sequence Data; D010447:Peptide Hydrolases / Q000187:drug effects / Q000378:metabolism; D011480:Protease Inhibitors / Q000097:blood / Q000494:pharmacology; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein; D017386:Sequence Homology, Amino Acid
D000925:Anticoagulants; D000991:Antithrombins; D060829:Arthropod Proteins; D001798:Blood Proteins; D018076:DNA, Complementary; D011480:Protease Inhibitors; C494419:amblin protein, Amblyomma hebraeum; D010447:Peptide Hydrolases