Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

High-affinity binding of very-long-chain fatty acyl-CoA esters to the peroxisomal non-specific lipid-transfer protein (sterol carrier protein-2).

ABSTRACT: Binding of fluorescent fatty acids to bovine liver non-specific lipid-transfer protein (nsL-TP) was assessed by measuring fluorescence resonance energy transfer (FRET) between the single tryptophan residue of nsL-TP and the fluorophore. Upon addition of pyrene dodecanoic acid (Pyr-C12) and cis-parinaric acid to nsL-TP, FRET was observed indicating that these fatty acids were accommodated in the lipid binding site closely positioned to the tryptophan residue. Substantial binding was observed only when these fatty acids were presented in the monomeric form complexed to beta-cyclodextrin. As shown by time-resolved fluorescence measurements, translocation of Pyr-C12 from the Pyr-C12-beta-cyclodextrin complex to nsL-TP changed dramatically the direct molecular environment of the pyrene moiety: i.e. the fluorescence lifetime of the directly excited pyrene increased at least by 25% and a distinct rotational correlation time of 7 ns was observed. In order to evaluate the affinity of nsL-TP for intermediates of the beta-oxidation pathway, a binding assay was developed based on the ability of fatty acyl derivatives to displace Pyr-C12 from the lipid binding site as reflected by the reduction of FRET. Hexadecanoyl-CoA and 2-hexadecenoyl-CoA were found to bind readily to nsL-TP, whereas 3-hydroxyhexadecanoyl-CoA and 3-ketohexadecanoyl-CoA bound poorly. The highest affinities were observed for the very-long-chain fatty acyl-CoA esters (24:0-CoA, 26:0-CoA) and their enoyl derivatives (24:1-CoA, 26:1-CoA). Binding of non-esterified hexadecanoic acid and tetracosanoic acid (24:0) was negligible.

SUBMITTER: Dansen TB

PROVIDER: S-EPMC1220144 | biostudies-other | 1999 Apr

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Defective peroxisomal catabolism of branched fatty acyl coenzyme A in mice lacking the sterol carrier protein-2/sterol carrier protein-x gene function.

Project description:Gene targeting in mice was used to investigate the unknown function of Scp2, encoding sterol carrier protein-2 (SCP2; a peroxisomal lipid carrier) and sterol carrier protein-x (SCPx; a fusion protein between SCP2 and a peroxisomal thiolase). Complete deficiency of SCP2 and SCPx was associated with marked alterations in gene expression, peroxisome proliferation, hypolipidemia, impaired body weight control, and neuropathy. Along with these abnormalities, catabolism of methyl-branched fatty acyl CoAs was impaired. The defect became evident from up to 10-fold accumulation of the tetramethyl-branched fatty acid phytanic acid in Scp2(-/-) mice. Further characterization supported that the gene disruption led to inefficient import of phytanoyl-CoA into peroxisomes and to defective thiolytic cleavage of 3-ketopristanoyl-CoA. These results corresponded to high-affinity binding of phytanoyl-CoA to the recombinant rat SCP2 protein, as well as high 3-ketopristanoyl-CoA thiolase activity of the recombinant rat SCPx protein.

| S-EPMC316706 | biostudies-literature

Peroxisomal acyl-CoA synthetases.

Project description:Peroxisomes carry out many essential lipid metabolic functions. Nearly all of these functions require that an acyl group-either a fatty acid or the acyl side chain of a steroid derivative-be thioesterified to coenzyme A (CoA) for subsequent reactions to proceed. This thioesterification, or "activation", reaction, catalyzed by enzymes belonging to the acyl-CoA synthetase family, is thus central to cellular lipid metabolism. However, despite our rather thorough understanding of peroxisomal metabolic pathways, surprisingly little is known about the specific peroxisomal acyl-CoA synthetases that participate in these pathways. Of the 26 acyl-CoA synthetases encoded by the human and mouse genomes, only a few have been reported to be peroxisomal, including ACSL4, SLC27A2, and SLC27A4. In this review, we briefly describe the primary peroxisomal lipid metabolic pathways in which fatty acyl-CoAs participate. Then, we examine the evidence for presence and functions of acyl-CoA synthetases in peroxisomes, much of which was obtained before the existence of multiple acyl-CoA synthetase isoenzymes was known. Finally, we discuss the role(s) of peroxisome-specific acyl-CoA synthetase isoforms in lipid metabolism.

| S-EPMC3382043 | biostudies-literature

FATP2 is a hepatic fatty acid transporter and peroxisomal very long-chain acyl-CoA synthetase.

Project description:Fatty acid transport protein (FATP)2, a member of the FATP family of fatty acid uptake mediators, has independently been identified as a hepatic peroxisomal very long-chain acyl-CoA synthetase (VLACS). Here we address whether FATP2 is 1) a peroxisomal enzyme, 2) a plasma membrane-associated long-chain fatty acid (LCFA) transporter, or 3) a multifunctional protein. We found that, in mouse livers, only a minor fraction of FATP2 localizes to peroxisomes, where it contributes to approximately half of the peroxisomal VLACS activity. However, total hepatic (V)LACS activity was not significantly affected by loss of FATP2, while LCFA uptake was reduced by 40%, indicating a more prominent role in hepatic LCFA uptake. This suggests FATP2 as a potential target for a therapeutic intervention of hepatosteatosis. Adeno-associated virus 8-based short hairpin RNA expression vectors were used to achieve liver-specific FATP2 knockdown, which significantly reduced hepatosteatosis in the face of continued high-fat feeding, concomitant with improvements in liver physiology, fasting glucose, and insulin levels. Based on our findings, we propose a model in which FATP2 is a multifunctional protein that shows subcellular localization-dependent activity and is a major contributor to peroxisomal (V)LACS activity and hepatic fatty acid uptake, suggesting FATP2 as a potential novel target for the treatment of nonalcoholic fatty liver disease.

| S-EPMC2944282 | biostudies-literature

Reprogramming acyl carrier protein interactions of an Acyl-CoA promiscuous trans-acyltransferase.

Project description:Protein interactions between acyl carrier proteins (ACPs) and trans-acting acyltransferase domains (trans-ATs) are critical for regioselective extender unit installation by many polyketide synthases, yet little is known regarding the specificity of these interactions, particularly for trans-ATs with unusual extender unit specificities. Currently, the best-studied trans-AT with nonmalonyl specificity is KirCII from kirromycin biosynthesis. Here, we developed an assay to probe ACP interactions based on leveraging the extender unit promiscuity of KirCII. The assay allows us to identify residues on the ACP surface that contribute to specific recognition by KirCII. This information proved sufficient to modify a noncognate ACP from a different biosynthetic system to be a substrate for KirCII. The findings form a foundation for further understanding the specificity of trans-AT:ACP protein interactions and for engineering modular polyketide synthases to produce analogs.

| S-EPMC4035391 | biostudies-literature

Malonyl-CoA: acyl carrier protein transacylase from Helicobacter pylori: Crystal structure and its interaction with acyl carrier protein.

Project description:Malonyl-CoA: acyl carrier protein transacylase (MCAT) is a critical enzyme responsible for the transfer of the malonyl moiety to holo-acyl carrier protein (ACP) forming the malonyl-ACP intermediates in the initiation step of type II fatty acid synthesis (FAS II) in bacteria. MCAT has been considered as an attractive drug target in the discovery of antibacterial agents. In this study, the crystal structure of MCAT from Helicobacter pylori (Hp) at 2.5 angstroms resolution is reported, and the interaction of HpMCAT with HpACP is extensively investigated by using computational docking, GST-pull-down, and surface plasmon resonance (SPR) technology-based assays. The crystal structure results reveal that HpMCAT has a compact folding composed of a large subdomain with a similar core as in alpha/beta hydrolases, and a similar ferredoxin-like small subdomain as in acylphosphatases. The docking result suggests two positively charged areas near the entrance of the active site of HpMCAT as the ACP-binding region. Binding assay research shows that HpMCAT demonstrates a moderately binding ability against HpACP. The solved 3D structure of HpMCAT is expected to supply useful information for the structure-based discovery of novel inhibitors against MCAT, and the quantitative study of HpMCAT interaction with HpACP is hoped to give helpful hints in the understanding of the detailed catalytic mechanisms for HpMCAT.

| S-EPMC2206670 | biostudies-literature

Deficiency of a Retinal Dystrophy Protein, Acyl-CoA Binding Domain-containing 5 (ACBD5), Impairs Peroxisomal β-Oxidation of Very-long-chain Fatty Acids.

Project description:Acyl-CoA binding domain-containing 5 (ACBD5) is a peroxisomal protein that carries an acyl-CoA binding domain (ACBD) at its N-terminal region. The recent identification of a mutation in the ACBD5 gene in patients with a syndromic form of retinal dystrophy highlights the physiological importance of ACBD5 in humans. However, the underlying pathogenic mechanisms and the precise function of ACBD5 remain unclear. We herein report that ACBD5 is a peroxisomal tail-anchored membrane protein exposing its ACBD to the cytosol. Using patient-derived fibroblasts and ACBD5 knock-out HeLa cells generated via genome editing, we demonstrate that ACBD5 deficiency causes a moderate but significant defect in peroxisomal β-oxidation of very-long-chain fatty acids (VLCFAs) and elevates the level of cellular phospholipids containing VLCFAs without affecting peroxisome biogenesis, including the import of membrane and matrix proteins. Both the N-terminal ACBD and peroxisomal localization of ACBD5 are prerequisite for efficient VLCFA β-oxidation in peroxisomes. Furthermore, ACBD5 preferentially binds very-long-chain fatty acyl-CoAs (VLC-CoAs). Together, these results suggest a direct role of ACBD5 in peroxisomal VLCFA β-oxidation. Based on our findings, we propose that ACBD5 captures VLC-CoAs on the cytosolic side of the peroxisomal membrane so that the transport of VLC-CoAs into peroxisomes and subsequent β-oxidation thereof can proceed efficiently. Our study reclassifies ACBD5-related phenotype as a novel peroxisomal disorder.

| S-EPMC5241743 | biostudies-literature

Structural insights into human ABCD3-mediated peroxisomal acyl-CoA translocation.

Project description:Human ABC transporters ABCD1-3 are all localized on the peroxisomal membrane and participate in the β-oxidation of fatty acyl-CoAs, but they differ from each other in substrate specificity. The transport of branched-chain fatty acids from cytosol to peroxisome is specifically driven by ABCD3, dysfunction of which causes severe liver diseases such as hepatosplenomegaly. Here we report two cryogenic electron microscopy (cryo-EM) structures of ABCD3 bound to phytanoyl-CoA and ATP at resolutions of 2.9 Å and 3.2 Å, respectively. A pair of phytanoyl-CoA molecules were observed in ABCD3, each binding to one transmembrane domain (TMD), which is distinct from our previously reported structure of ABCD1, where each fatty acyl-CoA molecule strongly crosslinks two TMDs. Upon ATP binding, ABCD3 exhibits a conformation that is open towards the peroxisomal matrix, leaving two extra densities corresponding to two CoA molecules deeply embedded in the translocation cavity. Structural analysis combined with substrate-stimulated ATPase activity assays indicated that the present structures might represent two states of ABCD3 in the transport cycle. These findings advance our understanding of fatty acid oxidation and the molecular pathology of related diseases.

| S-EPMC11369193 | biostudies-literature

CoA-dependent activation of mitochondrial acyl carrier protein links four neurodegenerative diseases.

Project description:PKAN, CoPAN, MePAN, and PDH-E2 deficiency share key phenotypic features but harbor defects in distinct metabolic processes. Selective damage to the globus pallidus occurs in these genetic neurodegenerative diseases, which arise from defects in CoA biosynthesis (PKAN, CoPAN), protein lipoylation (MePAN), and pyruvate dehydrogenase activity (PDH-E2 deficiency). Overlap of their clinical features suggests a common molecular etiology, the identification of which is required to understand their pathophysiology and design treatment strategies. We provide evidence that CoA-dependent activation of mitochondrial acyl carrier protein (mtACP) is a possible process linking these diseases through its effect on PDH activity. CoA is the source for the 4'-phosphopantetheine moiety required for the posttranslational 4'-phosphopantetheinylation needed to activate specific proteins. We show that impaired CoA homeostasis leads to decreased 4'-phosphopantetheinylation of mtACP. This results in a decrease of the active form of mtACP, and in turn a decrease in lipoylation with reduced activity of lipoylated proteins, including PDH. Defects in the steps of a linked CoA-mtACP-PDH pathway cause similar phenotypic abnormalities. By chemically and genetically re-activating PDH, these phenotypes can be rescued, suggesting possible treatment strategies for these diseases.

| S-EPMC6895606 | biostudies-literature

Structure of Mycobacterium tuberculosis mtFabD, a malonyl-CoA:acyl carrier protein transacylase (MCAT).

Project description:Mycobacteria display a unique and unusual cell-wall architecture, central to which is the membrane-proximal mycolyl-arabinogalactan-peptidoglycan core (mAGP). The biosynthesis of mycolic acids, which form the outermost layer of the mAGP core, involves malonyl-CoA:acyl carrier protein transacylase (MCAT). This essential enzyme catalyses the transfer of malonyl from coenzyme A to acyl carrier protein AcpM, thus feeding these two-carbon units into the chain-elongation cycle of the type II fatty-acid synthase. The crystal structure of M. tuberculosis mtFabD, the mycobacterial MCAT, has been determined to 3.0 A resolution by multi-wavelength anomalous dispersion. Phasing was facilitated by Ni2+ ions bound to the 20-residue N-terminal affinity tag, which packed between the two independent copies of mtFabD.

| S-EPMC2339739 | biostudies-literature

Yeast acyl-CoA-binding protein: acyl-CoA-binding affinity and effect on intracellular acyl-CoA pool size.

Project description:Acyl-CoA-binding protein (ACBP) is a 10 kDa protein characterized in vertebrates. We have isolated two ACBP homologues from the yeast Saccharomyces carlsbergensis, named yeast ACBP types 1 and 2. Both proteins contain 86 amino acid residues and are identical except for four conservative substitutions. In comparison with human ACBP, yeast ACBPs exhibit 48% (type 1) and 49% (type 2) conservation of amino acid residues. The amino acid sequence of S. carlsbergensis ACBP type 1 was found to be identical with the one ACBP present in Saccharomyces cerevisiae. A recombinant form of this protein was expressed in Escherichia coli and S. cerevisiae, purified, and its acyl-CoA-binding properties were characterized by isoelectric focusing and microcalorimetric analyses. The yeast ACBP was found to bind acyl-CoA esters with high affinity (Kd 0.55 x 10(-10) M). Overexpression of yeast ACBP in S. cerevisiae resulted in a significant expansion of the intracellular acyl-CoA pool. Finally, Southern-blotting analysis of the two genes encoding ACBP types 1 and 2 in S. carlsbergensis strongly indicated that this species is a hybrid between S. cerevisiae and Saccharomyces monacensis.

| S-EPMC1137253 | biostudies-other

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data