Showing papers on "Fatty acid-binding protein published in 1990"
TL;DR: A considerable body of indirect evidence is provided supporting a broad role for the FABP in the intracellular transport and metabolism of long-chain fatty acids and the existence of structure- and tissue-specific specialization of function among different members of the F ABP gene family.
Abstract: Cytosolic fatty acid binding proteins (FABP) belong to a gene family of which eight members have been conclusively identified. These 14–15 kDa proteins are abundantly expressed in a highly tissue-specific manner. Although the functions of the cytosolic FABP are not clearly established, they appear to enhance the transfer of long-chain fatty acids between artificial and native lipid membranes, and also to have a stimulatory effect on a number of enzymes of fatty acid metabolism in vitro. These findings, as well as the tissue expression, ligand binding properties, ontogeny and regulation of these proteins provide a considerable body of indirect evidence supporting a broad role for the FABP in the intracellular transport and metabolism of long-chain fatty acids. The available data also support the existence of structure- and tissue-specific specialization of function among different members of the FABP gene family. Moreover, FABP may also have a possible role in the modulation of cell growth and proliferation, possibly by virtue of their affinity for ligands such as prostaglandins, leukotrienes and fatty acids, which are known to influence cell growth activity. FABP structurally unrelated to the cytosolic gene family have also been identified in the plasma membranes of several tissues (FABPpm). These proteins have not been fully characterized to date, but strong evidence suggests that they function in the transport of long-chain fatty acids across the plasma membrane.
167 citations
TL;DR: The hepatic plasma membrane fatty acid-binding protein (h-FABPPM) and the mitochondrial isoenzyme of glutamic-oxaloacetic transaminase (mGOT) of rat liver have similar amino acid compositions and identical amino acid sequences for residues 3-24 and the relative specific activities of the membranes and purified protein suggest that h-FabPPM constitutes 1-2% of plasma membrane protein in the rat hepatocyte.
Abstract: The hepatic plasma membrane fatty acid-binding protein (h-FABPPM) and the mitochondrial isoenzyme of glutamic-oxaloacetic transaminase (mGOT) of rat liver have similar amino acid compositions and identical amino acid sequences for residues 3-24. Both proteins migrate with an apparent molecular mass of 43 kDa on SDS/polyacrylamide gel electrophoresis, have a similar pattern of basic charge isomers on isoelectric focusing, are eluted similarly from four different high-performance liquid chromatographic columns, have absorption maxima at 435 nm under acid conditions and 354 nm at pH 8.3, and bind oleate with a Ka approximately 1.2-1.4 x 10(7) M-1. Sinusoidally enriched liver plasma membranes and purified h-FABPPM have GOT enzymatic activity; the relative specific activities (units/mg) of the membranes and purified protein suggest that h-FABPPM constitutes 1-2% of plasma membrane protein in the rat hepatocyte. Monospecific rabbit antiserum against h-FABPPM reacts on Western blotting with mGOT, and vice versa. Antisera against both proteins produce plasma membrane immunofluorescence in rat hepatocytes and selectively inhibit the hepatocellular uptake of [3H]oleate but not that of [35S]sulfobromophthalein or [14C]taurocholate. The inhibition of oleate uptake produced by anti-h-FABPPM can be eliminated by preincubation of the antiserum with mGOT; similarly, the plasma membrane immunofluorescence produced by either antiserum can be eliminated by preincubation with the other antigen. These data suggest that h-FABPPM and mGOT are closely related.
150 citations
TL;DR: Current knowledge suggests that the function of this set of proteins reaches beyond simply aiding cytoplasmic solubilization of hydrophobic ligands, but that they can be assigned several regulatory roles in cellular lipid homeostasis.
Abstract: At least three different proteins are implicated in the cellular transport of fatty acid moieties: a plasmalemmal membrane and a cytoplasmic fatty acid-binding protein (FABPPM and FABPC, respectively) and cytoplasmic acyl-CoA binding protein (ACBP). Their putative main physiological significance is the assurance that long-chain fatty acids and derivatives, either in transit through membranes or present in intracellular compartments, are largely complexed to proteins. FABPC distinguishes from the other proteins in that distinct types of FABPC are found in remarkable abundance in the cytoplasmic compartment of a variety of tissues. Although their mechanism of action is not yet fully elucidated, current knowledge suggests that the function of this set of proteins reaches beyond simply aiding cytoplasmic solubilization of hydrophobic ligands, but that they can be assigned several regulatory roles in cellular lipid homeostasis.
111 citations
TL;DR: On their way from the capillary to the intracellular organelles, fatty acids have to pass a series of aqueous spaces and membrane barriers.
Abstract: Fatty acids are distributed by the bloodstream to peripheral tissues that utilize these molecules for energy production, for storage, or in biosynthetic pathways. Fatty acids are transported in plasma in the form of triacylglycerols in chylomicrons and very-low-density lipoproteins, or noncovalently bound to serum albumin. Lipoprotein lipase liberates the ester-bound fatty acids. On their way from the capillary to the intracellular organelles, fatty acids have to pass a series of aqueous spaces and membrane barriers (Figure 1). Fatty acids may be taken up from blood and transferred to the interstitial space by the endothelial cells of the capillary wall. Albumin-fatty acid complexes may also pass the endothelium through clefts or by way of plasmalemmal vesicles that pass through the capillary endothelial cell (Milici et al., 1987).
90 citations
TL;DR: The observed changes in L-cells as a result of de novo expression of L-FABP are consistent with the ability of this protein to bind sterols and fatty acids, stimulate sterol esterification, and stimulate phospholipid biosynthesis.
72 citations
TL;DR: Ffa transfer rates from both liver and heart FABP are independent of acceptor concentration and composition, suggesting that, at least in the case of model membrane acceptor vesicles, the mechanism of transfer is via aqueous diffusion rather than via collision of F ABP with membranes.
70 citations
TL;DR: The discovery of a fatty acid binding protein (FABP) in an invertebrate species for the first time supports the proposed function of muscle FABP as intracellular fatty acid receptor or transport protein.
69 citations
TL;DR: Fatty acid-binding proteins are now recognized as products of an ancient gene family comprised of at least 9 structurally related, soluble intracellular members, a number of which exhibit high-affinity binding of long-chain fatty acids.
Abstract: Fatty acid-binding proteins (FABPs) were first identified in the cytosol of rat intestinal mucosa during studies on the regulation of intestinal fatty acid uptake. The subsequent finding of FABP activity in the cytosol of many other tissues initially was believed to reflect a single protein. However, the FABPs are now recognized as products of an ancient gene family comprised of at least 9 structurally related, soluble intracellular members, a number of which exhibit high-affinity binding of long-chain fatty acids. Despite recent insights into regulation and tissue-specific expression suggesting FABPs to subserve diverse roles, their precise biological functions remain to be elucidated.
67 citations
TL;DR: In the course of the studies on the structural diversity of the isoforms of cardiac fatty acid-binding proteins (cFABPs), a cardiac-type FABP from the matrix of bovine heart mitochondria was purified to homogeneity and obtained as a single 15-kDa protein.
59 citations
TL;DR: Kinetic parameters for the binding of [1-14C]oleic acid by purified rat heart FABP, assayed in the presence of Triton X-100, were found to be similar to thoseAssessment of this assay showed that the use of aqueous FA solutions resulted in a Marked decrease in FA concentration due to their aspecific binding to the surface of the test-tube used.
Abstract: Fatty acid (FA) binding by fatty acid-binding protein (FABP) is frequently monitored with the so-called Lipidex 1000 assay, in which protein associated and non-protein bound FA are separated by selectively binding the latter to Lipidex 1000. Careful evaluation of this assay showed that the use of aqueous FA solutions resulted in a marked decrease (60 to 70%) of FA concentration due to their aspecific binding to the surface of the test-tube used. In addition, solutions of rat heart FABP in the micromolar range also showed a concentration decrease up to 80% due to protein binding to the surface of the test-tube. Introduction of detergents, Triton X-100 or Tween 20, limited the FA loss to less than 20% and totally eliminated FABP adsorption. Kinetic parameters for the binding of [1-14C]oleic acid by purified rat heart FABP, assayed in the presence of Triton X-100, were found to be similar to those assayed in the absence of detergent, when adequate corrections were made for losses of FA and FABP due to surface adsorption. Use of Tween 20 resulted in a substantial increase of the dissociation constant. The addition of 100 microM Triton X-100 to the assay medium considerably facilitates the determination of kinetic parameters of fatty acid-binding by proteins.
54 citations
TL;DR: E. coli-derived I-FABP not only represents a useful model for assessing the atomic details of fatty acid-protein interactions and the mechanisms which regulate acquisition and release of this type of ligand, but also structure/function relationships in other superfamily members.
Abstract: A prokaryotic expression vector containing the rec A promoter and a translational enhancer element from the gene 10 leader of bacteriophage T7 was used to direct efficient synthesis of rat intestinal fatty acid binding protein (I-FABP) in E. coli. Expression of I-FABP in E. coli has no apparent, deleterious effects on the organism. High levels of expression of I-FABP mRNA in supE+ strains of E. coli, such as JM101, is associated with suppression of termination at its UGA stop codon. This can be eliminated by using a sup-Estrain as MG1655 and by site-directed mutagenesis of the cDNA to create an in frame UAA stop codon. E. coli-derived rat I-FABP lacks its initiator Met residues. It has been crystallized with and without bound palmitate. High resolution x-ray crystallographic studies of the 131 residue apo- and holo-proteins have revealed the following. I-FABP contains 10 anti-parallel β-strands organized into two orthogonally situated β-sheets. The overall conformation of the protein resembles that of a clam — hence the term β-clam. The bound ligand is located in the interior of the protein. Its carboxylate group forms part of a unique five member hydrogen bonding network consisting of two ordered solvent molecules as well as the side chains of Arg106 and Gln115. The hydrocarbon chain of the bound C16:0 fatty acid has a distinctive bent conformation with a slight left-handed helical twist. This conformation is maintained by interactions with the side chains of a number of hydrophobic and aromatic amino acids. Apo-I-FABP has a similar overall conformation to holo-I-FABP indicating that the β-clam structure is stable even without bound ligand. The space occupied by bound ligand in the core of the holo-protein is occupied by additional ordered solvent molecules in the apo-protein. Differences in the side chain orientations pf several residues located over a potential opening to the cores of the apo- and holo-proteins suggest that solvent may play an important role in the binding mechanism. Comparison of the Cα coordinates of apo- and holo-I-FABP with those of other proteins indicates it is a member of a superfamily that currently includes (i) 10 mammalian intracellular lipid binding proteins, (ii) the photoactive yellow protein from the purple photoautotrophic bacterium Ectothiorhodospira halophila and (iii) a group of extracellular lipid binding proteins from a diverse number of phyla that have a common β ‘barrel’ consisting of 8 anti-parallel β-strands stacked in two nearly orthogonal sheets. In summary, E. coli-derived I-FABP not only represents a useful model for assessing the atomic details of fatty acid-protein interactions and the mechanisms which regulate acquisition and release of this type of ligand, but also structure/function relationships in other superfamily members.
TL;DR: Though mainly cytosolic in either case, immunoelectron microscopy as well as a gelchromatographic immunofluorescence assay demonstrate the association of hepatic FABP in liver cells with microsomal and outer mitochondrial membranes and with nuclei, whereas in heart cells cardiac FABPs is confined to mitochondria' matrix and nuclei.
Abstract: Based on sequence relationships the cytoplasmic fatty acid-binding proteins (FABPs) of mammalian origin are divided into at least three distinct types, namely the hepatic-, intestinal- and cardiac-type. Highly conserved sequences of FABPs within the same type correlate with immunological crossreactivities. Isoforms of hepatic-type FABP are found in several mammalian species and for bovine liver FABP specific shifts in isoelectric points upon lipidation with fatty acids are observed. Isoforms of intestinal-type FABP are not known and the occurrence of cardiac-type isoforms so far is confined to bovine heart tissue. A bovine mammary-derived growth inhibitor (MDGI) is 95% homologous to the cardiac-type FABP from bovine heart. Dissociation constants of FABP/fatty acid complexes are in the range of 1 μM and 1:1 stoichiometries are usually found, but the neutral isoform of hepatic FABP from bovine liver binds 2 fatty acids. On subcellular levels hepatic- and cardiac-type FABPs are differently distributed. Though mainly cytosolic in either case, immunoelectron microscopy as well as a gelchromatographic immunofluorescence assay demonstrate the association of hepatic FABP in liver cells with microsomal and outer mitochondrial membranes and with nuclei, whereas in heart cells cardiac FABP is confined to mitochondria' matrix and nuclei. In mammary epithelial cells MDGI is associated with neither mitochondria nor endoplasmic reticulum, and is expressed in a strictly developmental-dependent spatial and temporal pattern. The specific role proposed for MDGI is to arrest growth of mammary epithelial cells when they become committed to differentiation in the mammary gland.
TL;DR: A cytosolic protein, able to facilitate intermembrane movements of phospholipids in vitro, has been purified to homogeneity from sunflower seedlings and is able to bind oleoyl-CoA, as shown by FPLC chromatography.
Abstract: A cytosolic protein, able to facilitate intermembrane movements of phospholipids in vitro, has been purified to homogeneity from sunflower seedlings. This protein, which has the properties of a lipid-transfer protein (LTP), is also able to bind oleoyl-CoA, as shown by FPLC chromatography. This finding, in addition to previous observations suggesting that a lipid-transfer protein from spinach leaves can bind oleic acid and that oat seedlings contain a fatty acid-binding protein with similar features than lipid transfer proteins, provides a clear demonstration that plant cells contain bifunctional fatty acid/lipid transfer proteins. These proteins can play an active role in fatty acid metabolism which involves movements of oleyl-CoA between intracellular membranes.
TL;DR: Results indicate that fatty acids traverse the plasma membrane and are bound by ALBP in the cytoplasmic compartment and that lipid uptake in other cell systems, such as liver, heart, intestine, and nerve tissue, proceeds by a similar process.
TL;DR: Findings indicate a marked difference between CMC and non-myocytal cells in the heart regarding their capacity to oxidize fatty acids, and a marked disproportion between the fatty acid oxidation capacity and immunochemically determined FABP content in both CEC and CFLC.
Abstract: Heart tissue contains appreciable amounts of fatty acid-binding protein (FABP). FABP is thought to play a crucial role in the transport of fatty acids from the cellular membrane to the intracellular site of oxidation and also, in case of endothelial cells, in the transfer of fatty acids from the vascular to the interstitial compartment through the endothelial cytoplasm. The present study was designed to delineate a possible quantitative relationship between the capacity of different cell types in the heart to oxidize fatty acids and the presence of FABP. Palmitate oxidation capacity, measured in homogenates of cells isolated from adult rat hearts, was 2 nmol/min per mg tissue protein in freshly isolated cardiomyocytes (CMC), but only 0.09 and 0.31 nmol/min per mg tissue protein in cultivated endothelial (CEC) and fibroblast-like cells (CFLC), respectively. Palmitate oxidation rates were closely related to the cytochrome C oxidase activity and, hence, to the mitochondrial density in the cells under investigation. In CMC the content of cytosolic H-FABP (H-FABPc) was about 4.51 µg/mg tissue protein. However, in CEC and CFLC the FABP content was less than 0.01 and 0.004 µg/mg tissue protein, respectively, corresponding to at maximum 0.2% of the FABP content of CMC. These findings indicate a marked difference between CMC and non-myocytal cells in the heart regarding their capacity to oxidize fatty acids, and a marked disproportion between the fatty acid oxidation capacity and immunochemically determined FABP content in both CEC and CFLC. The functional implication of these observations remains to be elucidated.
TL;DR: Evidence is presented that FABP is a powerful regulator of acylcarnitine flux entering the mitochondrial β-oxidative system and appears to be an active link between the cytoplasm and the mitochondria, regulating the energy made available to the cell.
Abstract: Although abundant in most biological tissues and chemically well characterized, the fatty acid-binding protein (FABP) was until recently in search of a function. Because of its strong affinity for long chain fatty acids and its cytoplasmic origin, this protein was repeatedly claimed in the literature to be the transcytoplas-mic fatty acid carrier. However, techniques to visualize and quantify the movements of molecules in the cytoplasm are still in their infancy. Consequently the carrier function of FABP remains somewhat speculative. However, FABP binds not only fatty acids but also their CoA and carnitine derivatives, two typical molecules of mitochondrial origin. Moreover, it has been demonstrated and confirmed that FABP is not exclusively cytoplasmic, but also mitochondrial. A function for FABP in the mitochondrial metabolism of fatty acids plus CoA and carnitine derivatives would therefore be anticpated. Using spin-labelling techniques, we present here evidence that FABP is a powerful regulator of acylcarnitine flux entering the mitochondrial β-oxidative system. In this perspective FABP appears to be an active link between the cytoplasm and the mitochondria, regulating the energy made available to the cell. This active participation of FABP is shown to be the consequence of its gradient-like distribution in the cardiac cell, and also of the coexistence of multispecies of this protein produced by self-aggregation.
TL;DR: Experimental studies suggest that the acinar gradient of L-FABP is most likely to represent a response to physiological conditions existing in the intact acinus which may include gradients in the flux of fatty acids, fatty acid metabolites and hormones.
Abstract: Liver fatty acid-binding protein (L-FABP) is expressed in a declining gradient between the portal and central zones of the liver acinus. This paper discusses the results of experimental studies which address the questions: (a) What factors regulate L-FABP expression in liver and produce its acinar gradient? (b) What is the relationship between the acinar gradient of L-FABP and acinar gradients in the transport and metabolism of long-chain fatty acids? Both high-fat diets and clofibrate-treatment increase L-FABP proportionally at both extremes of the liver acinus and the small intestine, with preservation of the L-FABP gradient in both tissues. Female rats differ from males, however, in showing a greater hepatic abundance of L-FABP which is expressed almost equally throughout the acinus. Dietary studies show that L-FABP is induced with increased fatty acid flux derived from dietary fat but not from de novo hepatic fatty acid synthesis. Studies of the synthesis and utilization of fatty acids by hepatocytes isolated from the periportal and pericentral zones of the liver acinus suggest that the acinar gradient of L-FABP is not associated with differences in the instrinsic capacity of zone 1 and zone 3 hepatocytes to utilize or synthesize fatty acids. In addition, studies of the acinar uptake pattern of a fluorescent fatty acid derivative by isolated perfused livers indicate that the acinar distribution of L-FABP does not determine the pattern of fatty acid uptake in the intact acinus. Rather, the acinar gradient of L-FABP is most likely to represent a response to physiological conditions existing in the intact acinus which may include gradients in the flux of fatty acids, fatty acid metabolites and hormones.
TL;DR: These protein families in the intestine may have an important role as carriers in the initial step of arresting these exogenous pollutants.
TL;DR: The results show that the fluorescence emission spectra of AOffa bound to adipocyte FABP (A-FABP) are blue-shifted relative to heart FABp (H-F ABP), indicating that AOffA bound to A-FabP are held in a more constrained configuration.
Abstract: Murine adipocyte and rat heart fatty acid binding proteins (FABP) are closely related members of a family of cytosolic proteins which bind long-chain free fatty acids (ffa). The physical and chemical characteristics of the fatty acid binding sites of these proteins were studied using a series of fluorescent analogues of stearic acid (18:0) with an anthracene moiety covalently attached at seven different positions along the length of the hydrocarbon chain (AOffa). Previously, we used these probes to investigate the binding site of rat liver FABP (L-FABP) [Storch et al. (1989) J. Biol. Chem. 264, 8708-8713]. Here we extend those studies to adipocyte and heart FABP, two members of the FABP family which share a high degree of sequence homology with each other (62% identity) but which are less homologous with L-FABP (approximately 30%). The results show that the fluorescence emission spectra of AOffa bound to adipocyte FABP (A-FABP) are blue-shifted relative to heart FABP (H-FABP), indicating that AOffa bound to A-FABP are held in a more constrained configuration. For both proteins, constraint on the bound ffa probe is highest at the midportion of the acyl chain. Ffa are bound in a hydrophobic environment in both proteins. Excited-state lifetimes and fluorescence quantum yields suggest that the binding site of H-FABP is more hydrophobic than that of A-FABP. Nevertheless, acrylamide quenching experiments indicate that ffa bound to H-FABP are more accessible to the aqueous environment than are A-FABP-bound ffa.(ABSTRACT TRUNCATED AT 250 WORDS)
TL;DR: Data suggest that within a given neoplasm, differences exist in the differentiation programs of monoclonally-derived, malignant colonic epithelial cells and that liver fatty acid-binding protein is a useful marker for operationally defining these subpopulations.
TL;DR: Rat liver fatty acid‐binding protein (FABP) may transfer fatty acids to peroxisomes, but is not involved in the transport of acyl‐CoA through theperoxisomal membrane.
TL;DR: The results indicated better preservation of myocardial high-energy phosphate compounds, reduced creatine kinase and lactate dehydrogenase release from the heart, and improved coronary flow in hearts treated with fatty acid binding protein compared with untreated controls, suggest that fatty acidbinding protein may be used as a possible therapeutic agent to improve myCardial function during reperfusion of ischemic heart.
Abstract: In this study, fatty acid binding protein was used to protect an ischemic heart from reperfusion injury. Isolated rat heart was preperfused in the presence of 1.4 microM liposome-bound fatty acid binding protein for 15 minutes, followed by 30 minutes of ischemia and 30 minutes of reperfusion. Our results indicated better preservation of myocardial high-energy phosphate compounds (including ATP and creatine phosphate), reduced creatine kinase and lactate dehydrogenase release from the heart, and improved coronary flow in hearts treated with fatty acid binding protein compared with untreated controls. Fatty acid binding protein enhanced reacylation of arachidonic acid into phospholipids, thereby preserving membrane phospholipids and reducing free fatty acid contents during ischemia and reperfusion. In addition, fatty acid binding protein-bound long-chain free fatty acids and their thioesters as well as carnitine esters were increased in the cytosolic compartment of the heart. These results suggest that fatty acid binding protein may be used as a possible therapeutic agent to improve myocardial function during reperfusion of ischemic heart.
TL;DR: The general and functional name ‘fatty acid-binding protein’ (FABP) is preferred for the cellular proteins with the property to bind fatty acids, unless future research reveals that the binding of fatty acids is not the primary biological property or physiological role of (some of) these proteins.
Abstract: A variety of designations is currently being used to refer to cellular fatty acid-binding proteins (FABPs). Besides from the use of other general names (e.g. Z protein), confusion mostly arises from the application of various abbreviations and symbols to denote the tissue(s) of origin and cellular localization (cytoplasm, plasma membrane) of a specific FABP. In order to minimize confusion a more unified and rational nomenclature is proposed, which is based on application of the formula X-FABPY. The prefix X is a capital letter indicating the tissue of greatest abundance, the suffix Y similarly denotes the (sub)cellular localization of the protein. The general and functional name ‘fatty acid-binding protein’ (FABP) is preferred for the cellular proteins with the property to bind fatty acids, unless future research reveals that the binding of fatty acids is not the primary biological property or physiological role of (some of) these proteins
TL;DR: S-thiolation of L-FABP by glutathione decreased the affinity of the protein for unsaturated fatty acids without changing the equimolar maximum binding and this modification did not alter the affinity nor the maximum binding for saturated fatty acids.
Abstract: 0.16 ± 0.062% of the fatty acid-binding protein purified from 50 mM N-ethylmaleimide-treated rat liver (L-FABP) was determined as a form S-thiolated by glutathione (L-FABP-SSG). L-FABP-SSG, which was prepared in vitro through thiol – disulfide exchange reaction, showed more acidic pI (∼ 5.0) than the pI (∼ 7.0) of reduced L-FABP. S-thiolation of L-FABP by glutathione decreased the affinity of the protein for unsaturated fatty acids without changing the equimolar maximum binding. The changes in Kd were from 0.63 ± 0.054 μM to 1.03 ± 0.14 μM for oleic acid, from 0.63 ± 0.028 μM to 0.97 ± 0.12 μM for linoleic acid and from 0.85 ± 0.050 μM to 1.45 ± 0.024 μM for arachidonic acid. This modification did not alter the affinity nor the maximum binding for saturated fatty acids, which were determined to be Kd of ∼ 1.0 μM for palmitic acid and ∼ 0.9 μM for stearic acids, and equimolar maximum binding for both fatty acids. The binding affinity of L-FABP for unsaturated fatty acid may be regulated by redox state of the liver.
01 Jan 1990
TL;DR: An overview of studies on fatty acid-binding proteins and their role in cardiac fatty acid oxidation, regulation and relationship to the zonation of fatty acid metabolism.
Abstract: Historic overview of studies on fatty acid-binding proteins.- Detection, tissue distribution and (sub)cellular localization of fatty acid-binding protein types.- Fatty acid oxidation capacity and fatty acid-binding protein content of different cell types isolated from rat heart.- Localization of liver fatty acid-binding protein and its mRNA in the liver and jejunum of rats: an immunohistochemical and in situ hybridization study.- Amino acid sequence and some ligand binding properties of fatty acid-binding protein from bovine brain.- Type-specific immunodetection of human heart fatty acid-binding protein with polyclonal anti-peptide antibodies.- Bifunctional lipid-transfer: fatty acid-binding proteins in plants.- Characteristics of fatty acid-binding proteins and their relation to mammary-derived growth inhibitor.- Expression of a functionally active cardiac fatty acid-binding protein in the yeast, Saccharomyces cerevisiae.- Expression of fatty acid-binding protein from bovine heart in Escherichia coli.- Expression of rat intestinal fatty acid-binding protein in E. coli and its subsequent structural analysis: a model system for studying the molecular details of fatty acid-protein interaction.- Crystal structure of chicken liver basic fatty acid-binding protein at 2.7 A resolution.- 13C NMR studies of fatty acid-protein interactions: comparison of homologous fatty acid-binding proteins produced in the intestinal epithelium.- Assay of the binding of fatty acids by proteins: evaluation of the Lipidex 1000 procedure.- Fatty acid-binding protein from human heart localized in native and denaturing two-dimensional gels.- Revision of the amino acid sequence of human heart fatty acid-binding protein.- The chemical modification of cysteine-69 of rat liver fatty acid-binding protein (FABP): a fluorescence approach to FABP structure and function.- A comparison of heart and liver fatty acid-binding proteins: interactions with fatty acids and possible functional differences studies with fluorescent fatty acid analogues.- Role of fatty acid-binding proteins in cardiac fatty acid oxidation.- Modulation of fatty acid-binding capacity of heart fatty acid-binding protein by oxygen-derived free radicals.- Fatty acid-binding protein expression in the liver: its regulation and relationship to the zonation of fatty acid metabolism.- Effects of linoleic and gamma-linoleic acids (efamol evening primrose oil) on fatty acid-binding proteins of rat liver.- Quantitation of plasma membrane fatty acid-binding protein by enzyme dilution and monoclonal antibody based immunoassay.- The membrane fatty acid-binding protein is not identical to mitochondrial glutamic oxaloacetic transaminase (mGOT).- Renal palmitate transport: possible sites for interaction with a plasma membrane fatty acid-binding protein.- Fatty acid-binding to erythrocyte ghost membranes and transmembrane movement.- Acyl-CoA-binding (ACBP) and its relation to fatty acid-binding protein (FABP): an overview.- Liver fatty acid-binding protein in two cases of human lipid storage.- Nomenclature of fatty acid-binding proteins.- Cellular fatty acid-binding proteins: Current concepts and future directions.
TL;DR: Cardiac-type fatty acid-binding protein from human heart muscle of three individuals was isolated and characterized as pI 5.3-cFABP by tryptic peptide mapping, application of plasma desorption time-of-flight mass spectrometry and amino acid sequencing.
Abstract: Cardiac-type fatty acid-binding protein (cFABP) from human heart muscle of three individuals was isolated and characterized as pI 5.3-cFABP. The proteins were structurally analyzed by tryptic peptide mapping, application of plasma desorption time-of-flight mass spectrometry and amino acid sequencing. All three preparations of human heart FABP, having 132 amino acids, differed from the published sequence [Offner et al. Biochem J 251: 191–198, 1988] in position 104, where Leu is found instead of Lys, and in position 124, where Cys is found instead of Ser.
TL;DR: The principal absorptive cell of the rat small intestinal epithelium contains two homologous cytosolic proteins that bind long chain fatty acids, and liver FABP has been crystallized for eventual comparison with the known crystal structure of intestinal FABp.
TL;DR: Comparative 13C NMR results for FA interactions with FABP homologues from intestine are presented, and the functional implications of these analyses are discussed.
Abstract: A high-resolution, solution-state NMR method for characterizing and comparing the interactions between carboxyl 13C-enriched fatty acids (FA) and individual binding sites on proteins has been developed. The utility of this method results from the high degree of resolution of carboxyl from other carbon resonances and the high sensitivity of FA carboxyl chemical shifts to intermolecular environmental factors such as degree of hydrogen-bonding or hydration, degree of ionization (pH), and proximity to positively-charged or aromatic side-chain moieties in proteins. Information can be obtained regarding binding heterogeneity (structural as well as thermodynamic), binding stoichiometries, relative binding affinities, the ionization behavior of bound FA and protein side-chain moieties, the physical and ionization states of unbound FA, and the exchange rates of FA between protein binding sites and between protein and non-protein acceptors of FA, such as model membranes. Cytosolic fatty acid binding proteins represent an excellent model system for studying and comparing fatty acid-protein interactions. Prokaryotic expression vectors have been used to direct efficient synthesis of several mammalian intestinal FABPs in E. coli. This has enabled us to isolate gram-quantities of purified FABPs, to introduce NMR-observable isotopes, and to generate FABP mutants. The intestine is the only tissue known to contain abundant quantities of more than one FABP homologue in a single cell type. It is likely that these homologous FABPs serve distinct functional roles in intestinal lipid transport. This paper presents comparative 13C NMR results for FA interactions with FABP homologues from intestine, and the functional implications of these analyses are discussed.
TL;DR: In this article, a fatty acid-binding protein (FABP) from the cytosol of bovine brain was purified by Sephadex G-75 filtration and electrofocusing.
Abstract: A fatty acid-binding protein (FABP) from the cytosol of bovine brain was purified by Sephadex G-75 filtration and electrofocusing. The purified protein migrated as a single protein band in 15% polyacrylamide gel electrophoresis with an apparent molecular mass of 14.7 kDa. To ascertain that the purified protein was a FABP, it was submitted to fatty acid-binding tests. Oleic and palmitic acids bound to brain FABP but this was not the case for palmitoyl CoA. By Scatchard analysis the ligand binding values were: Kd = 0.28 µM, Bmax (mol/mol) = 0.6 for oleic acid and Kd = 0.8 µM, Bmax (mol/mol) = 2.1 for palmitic acid. The complete amino acid sequence of the brain FABP was determined and a microheterogeneity was observed. Sequence comparison with other FABPs of known sequence and the observed microheterogeneity demonstrated the presence in brain of several homologous FABPs closely related to heart FABP.