CUTICULAR HYDROCARBONS OF TRIATOMINS.

M. PATRICIA JUÁREZ AND GUSTAVO CALDERÓN FERNÁNDEZ

Pinamar

Congreso; XLI Reunión Anual de la Sociedad Argentina de Investigaciones Bioquímicas y Biología Molecular.; 2005

SAIB

CUTICULAR HYDROCARBONS OF TRIATOMINS. M. Patricia Juárez and Gustavo Calderón Fernández Instituto de Investigaciones Bioquímicas de La Plata (CONICET-UNLP), Facultad de Ciencias Médicas, calles 60 y 120, La Plata, 1900, Argentina. e-mail: mjuarez@isis.unlp.edu.ar   The subfamiliy Triatominae (Hemiptera: Reduviidae) include more than 130 species of insects, vectors of the Chagas Disease. The major vectorial capacities are shown by Triatoma infestans in South America and by Rhodnius prolixus, distributed through Mexico to Brazil. Triatomins cuticular surface is covered by a thin layer of lipids, mainly hydrocarbons, wax esters, fatty alcohols, and fatty acids. These compounds play a major role in preventing a lethal dessication, altering the absorption of chemicals and microorganism penetration, and participating in chemical communication events. Fatty acid synthases and fatty acyl-CoA elongases were first shown to provide very long chain precursors to cuticular hydrocarbons in T. infestans integument. Capillary gas chromatography coupled to mass spectrometry analyses showed that cuticular hydrocarbons of Triatominae are a complex mixture of saturated straight and methyl-branched chains, from 18 to more than 43 carbon atoms. Odd-chain hydrocarbons, mostly from 27 to 33 carbons, are the major straight chains. Different isomers of mono-, di-, tri-, and tetramethyl components mostly from 29 to 39 atoms in the carbon skeleton, account for the major methyl branched hydrocarbons. The presence, absence, and relative quantities of hydrocarbons determine the chemical phenotype of Triatominae and have been applied for differentiating genera, species, populations and sexes.