Revista Científica
versión impresa ISSN 0798-2259
Resumen
ROJAS VILLARROEL, Evelin et al. Lipidic Composition of Inner Mitochondrial Membrane from Ascaris suum. Rev. Cient. (Maracaibo) [online]. 2006, vol.16, n.2, pp.105-112. ISSN 0798-2259.
The lipids and proteins play an important role in cellular and subcellular membranes structure and function. Several researchers have studied mitochondrial membrane lipids from many organisms, observing mainly phospholipids (cardiolipin, phosphatidilethanolamine, phosphatidilserine) and cholesterol. The lipidic composition of inner mitochondrial membrane (mmi) of none helminthes has been determinate. Ascaris suum, one helminthe parasite that inhabits the small intestine of pig and metabolizes carbohydrates to short chain volatile fatty acids of in aerobic conditions, has been used as a model in comparative biochemistry studies. In this study, the mitochondrial fraction from Ascaris muscle was isolated by means of differential centrifugation in sucrose and the mmi was separated by centrifugation in 10mM Potassium Phosphate. The mmi lipidic fraction was extracted by Folch method and applied on plate for Thin Layer Chromatography (TLC). By mean of indirect enzymatic assays for cholesterol and triglycerides determination, and with TLC, cholesterol, phospholipid and other unknown lipid were found in parasite inner membrane. The fraction of phospholipids separated by TLC was extracted from silica gel with chlorophorm: methanol: H2O (30:50:20) and analyzed by Gas Chromatography (GC) to determine fatty acids composition. Oleic, palmitic, linoleic and stearic acid were present in 8.38; 7.98; 6.39 and 6.28%, respectively. Others acids as linolenic and miristic were found in minor proportion (1.65 and 0.50%), in concordance with reports of researches about mitochondrial lipidic composition in other organisms that suggests an important role of these fatty acids in mitochondrial function.
Palabras clave : Cholesterol; phospholipids; lipids; inner mitochondrial membrane; mitochondria.