Oleosins

Millichip, M. et al.. Purification and characterization of oil-bodies (oleosomes) and oil-body boundary proteins (oleosins) from the developing cotyledons of sunflower (Helianthus annuus L.), Biochem. J., 314, 333, 1996. 

In contrast to the analogous oleosins, which are phylogenetically related and share a common ancestor, phasins are functionally but not phylogenetically related [154]. For the binding of the phasins to the PHA granules different models... 

Hirudin Oleosin promoter/ nos terminator Fused to native oleosin B. napus 1% of seed protein 21... 

Oleosins are a class of seed proteins associated with oil-body membranes in developing and mature embryos. As a simple purification procedure, foreign peptides have been routinely fused with oleosin for the production of foreign proteins in plant seeds. Oleosin fusion facilitates protein purification via cleavage of the fusion protein by an endonuclease, followed by a flotation centrifugation procedure in which the oleosin fusion protein floats to the surface with the oil bodies, thus removing recombinant protein along with the oil-body fraction. 

The oleosin fusion procedure was used for the purification of the commercially valuable plant-based blood anticoagulant hirudin in transgenic Brassica carinata and Brassica napus. Hirudin, a natural protein from the medicinal leech Hirudo medicinalis, is superior to other anticoagulants such as heparin. Recombinant hirudin was cleaved from oil-bodies using endoproteinase Factor Xa. Released hirudin was biologically active, as determined by a colorimetric thrombin inhibition assay. 

Parmenter, D.L., Boothe, J.G.H., van Rooijen, G.J. Yeung, E.C., and Maloney, M.M. (1995). Production of biologically active hirudin in plant seeds using oleosin partitioning. Plant Mol. Biol. 29(6) 1167-1180. 

Oilseed rape Easy to exract protein using oleosin-fusion system... 

Safflower In safflower plants expressing biopharmaceuticals, the protein of interest is fused to oleosin, the protein that forms oil bodies within the safflower seeds. The seeds can be crushed and the oil bodies then easily purified by centrifugation. This oleosin-fusion protein system was first developed by SemBioSys Genetics, Inc., in safflower or oilseed rape. 

Proteins were then dissolved in 20 mL of 0.125 M Tris-HCl, pH 7.4 containing 1% (m/v) CHAPS and the protease inhibitor cocktail, and treated with CPLL. With several variations from the standard treatments such as other complementary extractions from seeds, the use of urea-containing extraction buffer, and an additional peptide ligand library, the total number of detected gene products was quite large. Two hundred and thirty one unique proteins were found in the pulp (vs. 56 described previously) and 61 in the seeds (vs. only four reported by the literature). In the latter case, the presence of seed storage proteins, oleosins, and histones were detected in the pulp, a thaumatin-like protein, an allergenic protein also named Ole el3, was confirmed. 

Leduc, V., Moneret-Vautrin, D.A., Tzen, J.T.C., Morisset, M., Guerin, L., and Kanny, G. 2006. Identification of oleosins as major allergens in sesame seed allergic patients. Allergy 61 349-356. 

Huang, A.H.C. 1992. Oil bodies and oleosins in seed. Ann Rev Plant Physiol Plant Mol Biol 43 177-200. 

Huang, A.H.C. 1996. Oleosins and oil bodies in seed of other organs. Plant Physiol 110 1055-1061. 

Pons, L., Chery, C., Mrabet, N., Schohn, H., Lapicque, F., and Gueant, J.-L. 2005. Purification and cloning of two high molecular mass isoforms of peanut seed oleosin encoded by cDNAs of equal sizes. Plant Physiol Biochem 43 659-668. 

Oleosins are hydrophobic plant proteins found only in association with small storage oil drops. These oil bodies are discrete spherical organelles, mainly composed of triacylglycerols and are surrounded by a phospholipids/oleosin annulus. Several oleosins were lately described, confirming that all of them comprise three distinct domains a conserved hydrophobic domain of about 70 amino acid residues being particularly rich in aliphatic amino acids flanked by an N- and a C-terminal domain, which are more hydrophilic with less conserved amino acid sequences. Allergenic oleosins were identified in sesame (Ses i 4 and Ses i 5), nuts (peanut and hazelnut oleosins), legumes, and seeds (Capuano et al. 2007, Leduc et al. 2006). 

Ross, J.H.E. and Murphy, D.J. (1 992) Biosynthesis and localisation of storage proteins, oleosins and lipids during seed development in Coriandrum sativum and other Umbelliferae. Plant Science Limerick 86(1), 59-70. 

Frandsen, G.I., Mundy, J., Tzen, J.T.C. 2001. Oil bodies and their associated proteins, oleosin and caleosin. Physiol. Plant. 112 301-307. 

Huang, A.H.G. Oil bodies and oleosins in seeds. Annu. Rev. Plant Physiol. Plant Mol Biol. 1992, 43, 177-200. 

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