Gene identification and proteomic analysis of the esterases of the cotton bollworm, Helicoverpa armigera

Testing the evolvability of an insect carboxylesterase for the detoxification of synthetic pyrethroid insecticides

“…Arguing against this however, several of the mutations correspond to quite common differences among paralogues in the two large databases of over two hundred insect carboxylesterase sequences compiled in Oakeshott et al (2010a) and Teese et al (2010). Thus the W251L, I140F, F309L, F421I and Y457N differences occur in 3%, 17%, 11%, 5% and 5% of the aligned sequences, respectively.…”

“…There are also significant numbers of physicochemically similar differences; for example the corresponding frequencies for F309T, F309S and F309I are 12%, 11% and 8%. Given that many insects appear to have complements of a dozen or more paralogous detoxifying esterases (Claudianos et al, 2006;Oakeshott et al, 2010a;Teese et al, 2010), it seems that there could be many options for evolving metabolic resistance to Type II SPs via structural changes in detoxifying esterases.…”

The classification of esterases: an important gene family involved in insecticide resistance - A review

“…However, early esterase studies addressed alpha and beta-naphthyl acetate substrates and it is still not clear how many of these isozymes actually belong to the carboxylesterase gene family. For example, although all seven of the Helicoverpa armigera isozymes identified by Teese et al (2010) belonged to the carboxylesterase gene family, Healy et al (1991) found that three out of the 22 identified D. melanogaster esterase isozymes did not. Interestingly, Hemingway (2000) argued that despite the high levels of malathion resistance in Anopheles populations, an increase in esterase activity was not observed in mosquito homogenates when conventional alpha and betanaphthyl acetate substrates were used.…”

Comparative analysis of the UDP-glycosyltransferase multigene family in insects

“…Thus it has been extensively studied in order to understand its ecology and physiology especially in relation to host plant adaptation and insecticide resistance (Heckel, 2010). Recently the H. armigera CCE gene family was described based on transcriptome analysis (Teese et al, 2010), which is likely incomplete based on comparison to the Bombyx genome; no other gene families related to detoxification have yet been described from this species.…”