Publications

• Cuticular wax biosynthesis in petunia petals: cloning and characterization of an alcohol-acyltransferase that synthesizes wax-esters.

  King A., Nam J.W., Han J., Hilliard J., Jaworski J.G.

  The surface of plants is covered by cuticular wax, which contains a mixture of very long-chain fatty acid (VLCFA) derivatives. This wax surface provides a hydrophobic barrier which reduces non-stomatal water loss. One component of the cuticular wax is the alkyl esters, which typically contain a VL ... >> More

  The surface of plants is covered by cuticular wax, which contains a mixture of very long-chain fatty acid (VLCFA) derivatives. This wax surface provides a hydrophobic barrier which reduces non-stomatal water loss. One component of the cuticular wax is the alkyl esters, which typically contain a VLCFA esterified to an alcohol of a similar length. As part of an EST project, we recently identified an acyltransferase with 19% sequence identity (amino acid) to a bacterial 'bifunctional' wax-ester synthase/diacylglycerol acyltransferase (WS/DGAT). Northern analysis revealed that this petunia homologue was expressed predominantly within the petals. The cDNA encoding the WS/DGAT homologue was introduced into a yeast strain deficient in triacylglycerol biosynthesis. The expressed protein failed to restore triacylglycerol biosynthesis, indicating that it lacked DGAT activity. However, isoamyl esters of fatty acids were detected, which suggested that the petunia cDNA encoded a wax-synthase. Waxes were extracted from petunia petals and leaves. The petal wax extract was rich in VLCFA esters of methyl, isoamyl, and short-to-medium straight chain alcohols (C4-C12). These low molecular weight wax-esters were not present in leaf wax. In-vitro enzymes assays were performed using the heterologously expressed protein and 14C-labelled substrates. The expressed protein was membrane bound, and displayed a preference for medium chain alcohols and saturated very long-chain acyl-CoAs. In fact, the activity would be sufficient to produce most of the low molecular wax-esters present in petals, with methyl-esters being the exception. This work is the first characterization of a eukaryotic protein from the WS/DGAT family. << Less

  Planta 226:381-394(2007) [PubMed] [EuropePMC]

  This publication is cited by 6 other entries.

• Identification of two novel human Acyl-CoA wax alcohol acyltransferases: members of the diacylglycerol acyltransferase 2 (DGAT2) gene superfamily.

  Turkish A.R., Henneberry A.L., Cromley D., Padamsee M., Oelkers P., Bazzi H., Christiano A.M., Billheimer J.T., Sturley S.L.

  The esterification of alcohols such as sterols, diacylglycerols, and monoacylglycerols with fatty acids represents the formation of both storage and cytoprotective molecules. Conversely, the overproduction of these molecules is associated with several disease pathologies, including atherosclerosis ... >> More

  The esterification of alcohols such as sterols, diacylglycerols, and monoacylglycerols with fatty acids represents the formation of both storage and cytoprotective molecules. Conversely, the overproduction of these molecules is associated with several disease pathologies, including atherosclerosis and obesity. The human acyl-CoA:diacylglycerol acyltransferase (DGAT) 2 gene superfamily comprises seven members, four of which have been previously implicated in the synthesis of di- or triacylglycerol. The remaining 3 members comprise an X-linked locus and have not been characterized. We describe here the expression of DGAT2 and the three X-linked genes in Saccharomyces cerevisiae strains virtually devoid of neutral lipids. All four gene products mediate the synthesis of triacylglycerol; however, two of the X-linked genes act as acyl-CoA wax alcohol acyltransferases (AWAT 1 and 2) that predominantly esterify long chain (wax) alcohols with acyl-CoA-derived fatty acids to produce wax esters. AWAT1 and AWAT2 have very distinct substrate preferences in terms of alcohol chain length and fatty acyl saturation. The enzymes are expressed in many human tissues but predominate in skin. In situ hybridizations demonstrate a differentiation-specific expression pattern within the human sebaceous gland for the two AWAT genes, consistent with a significant role in the composition of sebum. << Less

  J. Biol. Chem. 280:14755-14764(2005) [PubMed] [EuropePMC]

  This publication is cited by 11 other entries.