Abstract
The concept of lipase interfacial activation stems from the finding that the catalytic activity of most lipases depends on the aggregation state of their substrates. It is thought that activation involves the unmasking and structuring of the enzyme's active site through conformational changes requiring the presence of oil-in-water droplets. Here, we present the neutron structure of the activated lipase-colipase-micelle complex as determined using the D2O/H2O contrast variation low resolution diffraction method. In the ternary complex, the disk-shaped micelle interacts extensively with the concave face of colipase and the distal tip of the C-terminal domain of lipase. Since the micelle- and substrate-binding sites concern different regions of the protein complex, we conclude that lipase activation is not interfacial but occurs in the aqueous phase and is mediated by colipase and a micelle.
Full Text
The Full Text of this article is available as a PDF (570.2 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bernbäck S., Bläckberg L., Hernell O. Fatty acids generated by gastric lipase promote human milk triacylglycerol digestion by pancreatic colipase-dependent lipase. Biochim Biophys Acta. 1989 Feb 20;1001(3):286–293. doi: 10.1016/0005-2760(89)90113-6. [DOI] [PubMed] [Google Scholar]
- Breg J. N., Sarda L., Cozzone P. J., Rugani N., Boelens R., Kaptein R. Solution structure of porcine pancreatic procolipase as determined from 1H homonuclear two-dimensional and three-dimensional NMR. Eur J Biochem. 1995 Feb 1;227(3):663–672. doi: 10.1111/j.1432-1033.1995.tb20186.x. [DOI] [PubMed] [Google Scholar]
- Brogström B., Hildebrand H. Lipase and co-lipase activities of human small intestinal contents after a liquid test meal. Scand J Gastroenterol. 1975;10(6):585–591. [PubMed] [Google Scholar]
- Hermoso J., Pignol D., Kerfelec B., Crenon I., Chapus C., Fontecilla-Camps J. C. Lipase activation by nonionic detergents. The crystal structure of the porcine lipase-colipase-tetraethylene glycol monooctyl ether complex. J Biol Chem. 1996 Jul 26;271(30):18007–18016. doi: 10.1074/jbc.271.30.18007. [DOI] [PubMed] [Google Scholar]
- Hernell O., Staggers J. E., Carey M. C. Physical-chemical behavior of dietary and biliary lipids during intestinal digestion and absorption. 2. Phase analysis and aggregation states of luminal lipids during duodenal fat digestion in healthy adult human beings. Biochemistry. 1990 Feb 27;29(8):2041–2056. doi: 10.1021/bi00460a012. [DOI] [PubMed] [Google Scholar]
- Hofmann A. F., Small D. M. Detergent properties of bile salts: correlation with physiological function. Annu Rev Med. 1967;18:333–376. doi: 10.1146/annurev.me.18.020167.002001. [DOI] [PubMed] [Google Scholar]
- Jones T. A., Zou J. Y., Cowan S. W., Kjeldgaard M. Improved methods for building protein models in electron density maps and the location of errors in these models. Acta Crystallogr A. 1991 Mar 1;47(Pt 2):110–119. doi: 10.1107/s0108767390010224. [DOI] [PubMed] [Google Scholar]
- Lairon D., Nalbone G., Lafont H., Leonardi J., Domingo N., Hauton J. C., Verger R. Possible roles of bile lipids and colipase in lipase adsorption. Biochemistry. 1978 Nov 28;17(24):5263–5269. doi: 10.1021/bi00617a028. [DOI] [PubMed] [Google Scholar]
- Larsson A., Erlanson-Albertsson C. The identity and properties of two forms of activated colipase from porcine pancreas. Biochim Biophys Acta. 1981 Jun 23;664(3):538–548. doi: 10.1016/0005-2760(81)90131-4. [DOI] [PubMed] [Google Scholar]
- McIntyre J. C., Hundley P., Behnke W. D. The role of aromatic side chain residues in micelle binding by pancreatic colipase. Fluorescence studies of the porcine and equine proteins. Biochem J. 1987 Aug 1;245(3):821–829. doi: 10.1042/bj2450821. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Merritt E. A., Murphy M. E. Raster3D Version 2.0. A program for photorealistic molecular graphics. Acta Crystallogr D Biol Crystallogr. 1994 Nov 1;50(Pt 6):869–873. doi: 10.1107/S0907444994006396. [DOI] [PubMed] [Google Scholar]
- Morgan R. G., Barrowman J., Borgström B. The effect of sodium taurodesoxycholate and pH on the gel filtration behavior of rat pancreatic protein and lipases. Biochim Biophys Acta. 1969 Feb 4;175(1):65–75. doi: 10.1016/0005-2795(69)90146-9. [DOI] [PubMed] [Google Scholar]
- Patton J. S., Albertsson P. A., Erlanson C., Borgström B. Binding of porcine pancreatic lipase and colipase in the absence of substrate studies by two-phase partition and affinity chromatography. J Biol Chem. 1978 Jun 25;253(12):4195–4202. [PubMed] [Google Scholar]
- Pebay-Peyroula E., Garavito R. M., Rosenbusch J. P., Zulauf M., Timmins P. A. Detergent structure in tetragonal crystals of OmpF porin. Structure. 1995 Oct 15;3(10):1051–1059. doi: 10.1016/s0969-2126(01)00241-6. [DOI] [PubMed] [Google Scholar]
- SARDA L., DESNUELLE P. Action de la lipase pancréatique sur les esters en émulsion. Biochim Biophys Acta. 1958 Dec;30(3):513–521. doi: 10.1016/0006-3002(58)90097-0. [DOI] [PubMed] [Google Scholar]
- Sari H., Granon H., Sémériva M. Role of tyrosine residues in the binding of colipase to taurodeoxycholate micelles. FEBS Lett. 1978 Nov 15;95(2):229–234. doi: 10.1016/0014-5793(78)81000-x. [DOI] [PubMed] [Google Scholar]
- Timmins P. A., Poliks B., Banaszak L. The location of bound lipid in the lipovitellin complex. Science. 1992 Jul 31;257(5070):652–655. doi: 10.1126/science.1496377. [DOI] [PubMed] [Google Scholar]
- Timmins P., Pebay-Peyroula E., Welte W. Detergent organisation in solutions and in crystals of membrane proteins. Biophys Chem. 1994 Dec;53(1-2):27–36. doi: 10.1016/0301-4622(94)00073-5. [DOI] [PubMed] [Google Scholar]
- van Tilbeurgh H., Sarda L., Verger R., Cambillau C. Structure of the pancreatic lipase-procolipase complex. Nature. 1992 Sep 10;359(6391):159–162. doi: 10.1038/359159a0. [DOI] [PubMed] [Google Scholar]