Fecha de publicación: 30/12/2009 Fuente: WIPO "varroa" The invention discloses a chitinase ChiCl for deactivating a varroa destructor and application thereof. In the invention, The chitinase ChiCl for deactivating the varroa destructor is prepared by cloning a gene base sequence from a genome DNA of serratia marcescens GEI, and applying a procaryon expression carrier pET-32a(+) to express the gene in colon bacillus. Purification, renaturation and bioassay are carried out on a protein coded by the gene, a result shows that the protein has toxicity to the varroa destructor, and under a condition that the activity of the chitinase ChiCl is 14.7 U/ml, the varroa destructor transfected by the protein has a mortality rate of 25 percent after 5 days. Sequencing analysis shows that the gene is a new sequence of chitinase gene ChiCl types. The invention can be used in an aspect of preventing the mite damage of bees.