Enhanced activity of an insecticidal protein, trypsin modulating oostatic factor (TMOF), through conjugation with aliphatic polyethylene glycol.

Abstract

BACKGROUND:

Trypsin modulating oostatic factor (TMOF), a decapeptide (Tyr-Asp-Pro-Ala-Pro(6)) isolated from the ovaries of the adult yellow fever mosquito, Aedes aegypti, regulates trypsin biosynthesis. TMOF per os is insecticidal to larval mosquitoes and a good model for the development of technologies to enhance protein insecticide activity by reduced catabolism and/or enhanced delivery to the target.

RESULTS:

TFA-TMOF-K (TFA = trifluoro acetyl) allowed the specific conjugation of monodispersed, aliphatic polyethylene glycol (PEG) to the amino group of lysine-producing TMOF-K-methyl(ethyleneglycol)(7)-O-propionyl (TMOF-K-PEG(7) P). The addition of lysine to TMOF reduced its per os larval mosquitocidal activity relative to the parent TMOF, but conjugation of TMOF-K with methyl(ethyleneglycol)(7)-O-propionyl increased its toxicity 5.8- and 10.1-fold above that of TMOF and TMOF-K for Ae. aegypti. Enhanced insecticidal activity was also found for larval Ae. albopictus and for neonates of Heliothis virescens and Heliocoverpa zea. Only TMOF-K was found by MS/MS in the hemolymph for H. virescens fed on TMOF-K-PEG(7) P. No TMOF, TMOF-K or PEGylated TMOF-K was detected in the hemolymph after topical applications.

CONCLUSIONS:

This research suggests that aliphatic PEG polymers can be used as a new method for increasing the activity of insecticidal proteins.

• Authors: Laura A Jeffers, Hongyan Shen, Sayed Khalil, Brooke W Bissinger, Alan Brandt, T Brent Gunnoe, R Michael Roe
• Journal: Pest management science (Pest Manag Sci) Vol. 68 Issue 1 Pg. 49-59 (Jan 2012) ISSN: 1526-4998 [Electronic] England
• PMID: 21710555 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)
• Copyright: Copyright © 2011 Society of Chemical Industry.

Chemical References

• Insecticides
• Oligopeptides
• Peptide oostatic hormone
• Polyethylene Glycols

Topics

• Aedes (drug effects, growth & development)
• Animals
• Insecticides (chemical synthesis, chemistry, pharmacology)
• Larva (drug effects, growth & development)
• Moths (drug effects)
• Oligopeptides (chemistry, pharmacology)
• Polyethylene Glycols (chemistry)