Oil-bodies as substrates for lipolytic enzymes
| Autor: | Vincent Arondel, Natalie Ferté, Robert Verger, Ségolène Bruley, Robert Voultoury, Frédéric Beisson |
|---|---|
| Přispěvatelé: | Laboratoire Enzymologie Interfaciale et de Physiologie de la Lipolyse - UPR9025 (EIPL), Université de la Méditerranée - Aix-Marseille 2-Université de Provence - Aix-Marseille 1-Centre National de la Recherche Scientifique (CNRS), Laboratoires Yves Rocher |
| Jazyk: | angličtina |
| Rok vydání: | 2001 |
| Předmět: |
0106 biological sciences
Lipolysis [SDV]Life Sciences [q-bio] Phospholipid Plant Development Phospholipase Colipase 01 natural sciences Substrate Specificity 03 medical and health sciences chemistry.chemical_compound Oil body Plant Oils Lipase Molecular Biology Phospholipids Triglycerides ComputingMilieux_MISCELLANEOUS 030304 developmental biology chemistry.chemical_classification 0303 health sciences biology food and beverages Cell Biology Plants Enzyme chemistry Biochemistry biology.protein Oleosin 010606 plant biology & botany |
| Zdroj: | Biochimica et Biophysica Acta Molecular and Cell Biology of Lipids Biochimica et Biophysica Acta Molecular and Cell Biology of Lipids, Elsevier, 2001, 1531 (1-2), pp.47-58. ⟨10.1016/s1388-1981(01)00086-5⟩ Biochimica et Biophysica Acta Molecular and Cell Biology of Lipids, 2001, 1531 (1-2), pp.47-58. ⟨10.1016/s1388-1981(01)00086-5⟩ |
| ISSN: | 1388-1981 |
| DOI: | 10.1016/s1388-1981(01)00086-5⟩ |
| Popis: | Plant seeds store triacylglycerols (TAGs) in intracellular organelles called oil-bodies or oleosomes, which consist of oil droplets covered by a coat of phospholipids and proteins. During seed germination, the TAGs of oil-bodies hydrolysed by lipases sustain the growth of the seedlings. The mechanism whereby lipases gain access to their substrate in these organelles is largely unknown. One of the questions that arises is whether the protein/phospholipid coat of oil-bodies prevents the access of lipase to the oil core. We have investigated the susceptibility of almond oil-bodies to in vitro lipolysis by various purified lipases with a broad range of biochemical properties. We have found that all the enzymes assayed were capable of releasing on their own free fatty acids from the TAG of oil-bodies. Depending on the lipase, the specific activity measured on oil-bodies using the pH-stat technique was found to range from 18 to 38% of the specific activity measured on almond oil emulsified by gum arabic. Some of these lipases are known to have a dual lipase/phospholipase activity. However, no correlation was found to exist between the ability of a lipase to readily and efficiently hydrolyse the TAG content of oil-bodies and the presence of a phospholipase activity. Kinetic studies indicate that oil-bodies behave as a substrate as other proteolipid organelles such as milk fat globules. Finally we have shown that a purified water-soluble plant lipase on its own can easily hydrolyse oil-bodies in vitro. Our results suggest that the lipolysis of oil-bodies in seedlings might occur without any pre-hydrolysis of the protein coat. |
| Databáze: | OpenAIRE |
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