A cDNA encoding a chitinase from the epithelial cell line of Chironomus tentans (Insecta, Diptera) and its functional expression

A cDNA coding for chitinase was isolated from Chironomus cells, which posse sses conserved regions I and II characteristic for family 18 chitinases, a C-terminus enriched in Glu and Pro without the typical "PEST-region," putat ive glycosylation sites, a reduced number of C-terminal cysteines, and no t ypical chitin binding domain. Northern blots revealed one specific signal w ith an apparent size of 2.3 kb. The cDNA was expressed in the baculovirus/S podoptera system as a His-tag fusion protein, which was secreted as a funct ionally active enzyme into the medium and could be separated from endogenou s viral and Spodoptera-specific chitinases. Arch. Insect Biochem, Physiol. 45:24-36, 2000. (C) 2000 Wiley-Liss, Inc.