Fenitrothion-Caused Structural and Functional Perturbations in the Yolk Lipoproteins of Shrimp Macrobrachium borellii

GARCIA CF; GONZALEZ-BARÓ M. R; H GARDA; CUNNINGHAM ML.,; POLLERO R. J.

LIPIDS

Año: 2004 vol. 39 p. 389 - 396

0024-4201

Two lipovitellin (LV) forms containing the same apoproteins but differing in their lipid composition were isolated from Macrobrachium borellii eggs at early (LVe) and late (LVl) embryogenic stages and characterized. These two forms of LV, as well as liposomes prepared with lipids extracted from them, were used as simpler models to study the effect of the pesticide fenitrothion (FS) on their structures and functions. Rotational diffusion and fluorescence lifetime of two fluorescent probes (DPH and DPH-PA) were used to obtain information on structural changes induced by the FS in the inner and outer regions, respectively. Comparison of the rotational behavior of these probes in native LVs and liposomes (LPs) from extracted LV lipids suggests that apoprotein-lipid interactions result in an ordered neutral lipid core. FS increases the lipid phase polarity of both LVs and LPs forms. The rotation of these probes in LPs was not affected, suggesting a dependence of FS action on lipid-protein interactions. DPH-PA steady-state anisotropy shows that opposite to LVe, LVl form was sensitive to extremely low FS concentrations. FS increases differently the ability of both LVs to transfer palmitic acid to albumin. Such differences in the sensitivity of the LVs at different steps of embryogenesis to FS influence the toxical action of this insecticide.