Protein lipid-binding

Catalysts Based on Hollow Lipid-binding Proteins 

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Figure 9 Relative accuracy of comparative models. Upper left panel, comparison of homologous structures that share 40% sequence identity. Upper right panel, conformations of ileal lipid-binding protein that satisfy the NMR restraints set equally well. Lower left panel, comparison of two independently determined X-ray structures of interleukin 1(3. Lower right panel, comparison of the X-ray and NMR structures of erabutoxin. The figure was prepared using the program MOLSCRIPT [236].

A. Ligand Specificity of Brain Lipid-Binding Protein... 

LZ Xu, R Sanchez, A Sail, N Hemtz. Ligand specificity of brain lipid binding protein. I Biol Chem 271 24711-24719, 1996. 

There is a second family of small lipid-binding proteins, the P2 family, which include among others cellular retinol- and fatty acid-binding proteins as well as a protein, P2, from myelin in the peripheral nervous system. However, members of this second family have ten antiparallel p strands in their barrels compared with the eight strands found in the barrels of the RBP superfamily. Members of the P2 family show no amino acid sequence homology to members of the RBP superfamily. Nevertheless, their three-dimensional structures have similar architecture and topology, being up-and-down P barrels. 

Of all the novel protein types found in nematodes, only two have had biochemical activites ascribed, and these both happen to be lipid-binding proteins (LBPs). This chapter will focus on these, plus those that are structurally similar to those of vertebrates but appear to have nematode-specific modifications to their structures and functions. 

As-p18, the First Secreted Cytoplasmic Lipid-binding Protein... 

The various types of novel lipid-binding protein from nematodes can... 

Finally, there are the questions that these novel proteins pose. Do any of these unusual lipid-binding proteins, or modifications of otherwise usual proteins, have any role in parasitism Are they secreted to the advantage of the parasite and, if so, in what way ... 

Barrett, J., Saghir, N., Timanova, A., Clarke, K and Brophy, P.M. (1997) Characterisation and properties of an intracellular lipid-binding protein from the tapeworm Moniezia expansa. European Journal of Biochemistry 250, 269-275. 

Janssen, D. and Barrett, J. (1995) A novel lipid-binding protein from the cestode Moniezia expansa. BiochemicalJournal ill, 49—57. 

Kennedy, M.W. (2000b) The polyprotein lipid binding proteins of nematodes. Biochimica et Biophysica Acta 1472,149-164. 

Kennedy, M.W. and Beauchamp, J. (2000) Sticky finger interaction sites on cytosolic lipid binding proteins Cellular and Molecular Life Sciences 57, 1379-1387. 

Kennedy, M.W., Britton, C., Price, N.C., Kelly, S.M. and Cooper, A. (1995c) The DvA-1 polyprotein of the parasitic nematode Dictyocaulus viviparus. a small helix-rich lipid-binding protein. Journal of Biological Chemistry 270, 19277-19281. 

LaLonde, J.M., Levenson, M.A., Roe,J.J., Bemlohr, D.A. and Banaszak, L.J. (1994) Adipocyte lipid-binding protein complexed with arachidonic acid titration calorimetry and X-ray crystallographic studies. Journal of Biological Chemistry 269, 25339-25347. 

Shen, W.-E., Sridhar, K., Bernlohr, D.A. and Kraemer, F.B. (1999) Interaction of rat hormone-sensitive lipase with adipocyte lipid-binding protein. Proceedings of the National Academy of Sciences USA 96, 5528—5532. 

Simpson, MA, LiCata, V.J., Coe, N.R. and Bernlohr, D.A. (1999) Biochemical and biophysical analysis of the intracellular lipid binding proteins of adipocytes. Molecular and Cellular Biochemistry 192, 33—40. 

Martenson, R. and Uyemura, K. Myelin P2, a neuritogenic member of the family of cytoplasmic lipid binding proteins. In R. E. Martenson (ed.), Myelin biology and chemistry. Boca Raton, FL CRC Press, 1992, pp. 509-530. 

A semi-synthetic metalloenzyme that catalyses the enantioselective hydrolysis of simple amino acid esters has been reported. Iodoacetamido-l,10-phenanthroline (238) was interacted with a cysteine residue in adipocyte lipid binding protein (ALBP) to produce the conjugate ALBP-Phen (239), which was converted into its Cu(II) complex. The ALBP-Phen-Cu(II) was found to catalyse the enantioselective... 

T.A. Lipid-binding proteins a family of fatty acid and retinoid transport proteins. Adv. Protein Chem. 1994, 45, 89-151. 

The foam-negative effects of lipids can also be counteracted with the addition of a lipid-binding protein, wheat puroindoline (PIN), to beer. The PIN may bind the residual free lipids in such a way that they can no longer destabilize the foam. (Adapted from Cooper et ah, 2002)... 

Cooper, D. J. Husband, F. A. Mills, E. N. C. Wilde, P. J. Role of Beer Lipid-Binding Proteins in Preventing Lipid Destabilization of Foam. J. Agric. Pood Chem. 2002, 50, 7645-7650. 

The major lipoproteins of insect hemolymph, the lipophorins, transport diacylglycerols. The apolipo-phorins have molecular masses of -250, 80, and sometimes 18 kDa.34-37a The three-dimensional structure of a small 166-residue lipophorin (apolipophorin-III) is that of a four-helix bundle. It has been suggested that it may partially unfold into an extended form, whose amphipathic helices may bind to a phospholipid surface of the lipid micelle of the lipophorin 35 A similar behavior may be involved in binding of mammalian apolipoproteins. Four-helix lipid-binding proteins have also been isolated from plants.38 See also Box 21-A. Specialized lipoproteins known as lipovitellins... 

A third group of lipid-binding proteins have a four-helix bundle structure. They include the insect lipophorins, which transport diacylglycerols in the hemolymph (see main text), and nonspecific lipid carriers of green plants.q An 87-residue four-helix protein with a more open structure binds acyl-coenzyme A molecules in liver.r... 

Several other proteins that bind emulsifiers follow the general trends of this model. For example, the properties of the lipid binding protein from wheat called puroindoline has broadly similar properties [15]. 

The blue netlike surface in Plate 2 is also a contour map of a three-dimensional function. It represents a surface on which the electron density p(x,y,z) of adipocyte lipid binding protein (ALBP) is constant. Imagine that the net encloses 98% (or some specified value) of the protein s electron density, and so the net is in essence an image of the protein s surface. 

Following is a somewhat idealized description of how map fitting may proceed, illustrated with views from a modern map-fitting program. The maps and models are from the structure determination of adipocyte lipid binding protein (ALBP), which I will discuss further in Chapter 8. 

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