Tick chitinase

Abstract

A novel chitinase, a polynucleotide encoding the same, a vector and a transformant comprising the polynucleotide, an antibody against the chitinase, and a screening method for screening a substance capable of modifying the chitinase, are disclosed. According to the chitinase, polynucleotide, or vector, it is possible, for example, to exterminate ticks, or to treat or prevent tick-borne infections such as piroplasmosis, Q fever, or viral encephalitis.

1 . A method for treating or preventing a tick-borne infection, comprising administering to a subject in need thereof a polypeptide selected from the group consisting of:
 (1) a polypeptide consisting of the amino acid sequence of SEQ ID NO: 2;   (2) a polypeptide comprising the amino acid sequence of SEQ ID NO: 2 and exhibiting a chitinase activity;   (3) a polypeptide exhibiting a chitinase activity and comprising an amino acid sequence in which one or plural amino acids are substituted, deleted, and/or inserted at one or plural positions in the amino acid sequence of SEQ ID NO: 2; and   (4) a polypeptide comprising an amino acid sequence having a 60% or more homology with the amino acid sequence of SEQ ID NO: 2, and exhibiting a chitinase activity,   
       or a fragment of the polypeptide in an amount effective therefor. 
     
     
         2 . The method according to  claim 1 , wherein the fragment of the polypeptide is an immunogenic fragment of the polypeptide. 
     
     
         3 . The method according to  claim 1 , wherein the polypeptide is a polypeptide consisting of the amino acid sequence of SEQ ID NO: 2. 
     
     
         4 . The method according to  claim 1 , wherein the polypeptide is a polypeptide comprising the amino acid sequence of SEQ ID NO: 2 and exhibiting a chitinase activity. 
     
     
         5 . The method according to  claim 1 , wherein the polypeptide is a polypeptide comprising an amino acid sequence having a 70% or more homology with the amino acid sequence of SEQ ID NO: 2, and exhibiting a chitinase activity. 
     
     
         6 . The method according to  claim 1 , wherein the polypeptide is a polypeptide comprising an amino acid sequence having a 80% or more homology with the amino acid sequence of SEQ ID NO: 2, and exhibiting a chitinase activity. 
     
     
         7 . The method according to  claim 1 , wherein the polypeptide is a polypeptide comprising an amino acid sequence having a 90% or more homology with the amino acid sequence of SEQ ID NO: 2, and exhibiting a chitinase activity. 
     
     
         8 . The method according to  claim 1 , wherein the polypeptide is a polypeptide comprising an amino acid sequence having a 95% or more homology with the amino acid sequence of SEQ ID NO: 2, and exhibiting a chitinase activity.