Analysis of interactions between proteins and fatty acids or cholesterol using a fatty acid/cholesterol pull-down assay

Beck-García, Esmeralda; Beck-García, Katharina; Schlösser, Andreas; Schamel, Wolfgang W. A.

doi:10.1016/j.ab.2013.01.026

Cited by 11 publications

(9 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…CS is much less abundant than cholesterol under normal physiological conditions 34 , 35 . Because CS is able to reduce TCR nanoclusters despite an excess of cholesterol in the plasma membrane, we asked whether it could compete with cholesterol for TCR binding in vitro by using a lipid-protein pull down method 36 . T cell lysates were incubated with cholesterol-conjugated beads, then various free lipids were added to compete with the pre-formed interaction between cholesterol and TCR.…”

Section: Resultsmentioning

confidence: 99%

Inhibition of T cell receptor signaling by cholesterol sulfate, a naturally occurring derivative of membrane cholesterol

et al. 2016

View full text Add to dashboard Cite

Most adaptive immune responses require the activation of specific T cells through the T cell antigen receptor–CD3 complex (TCR). Here we show that cholesterol sulfate (CS), a naturally occurring analog of cholesterol, inhibits CD3 ITAM phosphorylation, a crucial first step in T cell activation. Biochemical studies show that CS disrupted TCR multimers, apparently by displacing cholesterol, known to bind TCRβ. Moreover, CS-deficient mice displayed a heightened sensitivity to a self-antigen, whereas increasing CS content by intrathymic injection inhibited thymic selection, indicating that this molecule is an intrinsic regulator of thymocyte development. These results reveal a regulatory role for CS in TCR signaling and thymic selection, highlighting the importance of the membrane microenvironment in modulating cell surface receptor activation.

show abstract

Section: Resultsmentioning

confidence: 99%

Inhibition of T cell receptor signaling by cholesterol sulfate, a naturally occurring derivative of membrane cholesterol

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Grains with black testa also displayed reduced acidity after processing (p<0.05), but no difference was observed between the two processes; the rose and red grains remained unchanged after both microwave and oven roasting. The reduction of lipid acidity during processing in grains with striped and black testa can be attributed to interactions such as the formation of complexes between sugars, free fatty acids and proteins (BECK-GARCÍA et al, 2013), resulting in reduced acid properties in the oil. These interactions are responsible for altering protein conformation, reducing solubility ( Figure 3C), modifying the flavor, aroma and color, and Reducing sugars, browning index, soluble protein and crude protein content of peanut grains with striped, rose, red and black testa subjected to the roasting process in a microwave or an oven.…”

Section: Resultsmentioning

confidence: 99%

Sensory and chemical properties of peanut grains (Arachis hypogaea L) roasted in microwave or oven

Ziegler

Ferreira

Rockembach

et al. 2017

SCA

View full text Add to dashboard Cite

Peanut grains are an excellent source of proteins and lipids. Before consumption, peanuts are subjected to a roasting process to acquire desirable sensory characteristics, in addition to eliminating microorganisms present. However, this processing step can cause various changes in lipid and protein fraction of grains, which are not totally elucidated in the literature. This study evaluated parameters such as the lipid acidity, peroxide value, primary (K 232 ) and secondary (K 270 ) products of lipid oxidation, fatty acid profile, reducing sugars, browning index, protein solubility, protein content and intention to purchase of peanut kernels with four colors of testa (striped, rose, red and black), subjected to the roasting process in microwave or oven. After processing, there was a reduction in lipid acidity and unsaturated fatty acids and an increase in saturated fatty acids, peroxide value, K 232 and K 270 in oil. There was a reduction in protein solubility and reducing sugars, with an increase in browning index. The purchase intention was higher for microwave-roasted red and rose peanut grains, which makes this form of processing interesting due to its convenience and speed. Key words: Oxidative stability. Peanuts. Roasting. Sensory and chemical properties. ResumoOs grãos de amendoim são excelente fonte de proteínas e lipídios. Antes de serem consumidos, os grãos de amendoim são submetidos a um processo de torrefação para adquirir características sensoriais desejáveis, além de eliminar os microrganismos presentes, no entanto, essa etapa de processamento pode causar várias alterações na fração lipídica e proteica dos grãos, as quais não são totalmente elucidadas pela literatura. Esse estudo avaliou parâmetros como a acidez lipídica, o índice de peróxidos, os produtos primários (K 232 ) e secundários (K 270 ) de oxidação lipídica, o perfil de ácidos graxos, açúcares redutores, índice de escurecimento, solubilidade proteica, teor de proteína e intenção de compra de grãos de amendoim com quatro cores de tegumento (listrado, rosa, vermelho e preto), submetidos ao processo de torrefação em micro-ondas ou forno. Após o processamento, ocorreu uma redução da acidez lipídica e de ácidos graxos poli-insaturados e um aumento de ácidos graxos saturados, índice de peróxidos, K 232 e K 270 no óleo. Houve uma redução da solubilidade proteica e de açúcares redutores, com aumento no índice de escurecimento. A intenção de compra foi maior nos grãos de amendoim vermelho e rosa torrados em micro-ondas, o que torna essa forma de processamento interessante devido a sua rapidez e conveniência. Palavras-chave: Amendoim. Estabilidade oxidativa. Torrefação. Propriedades químicas e sensoriais.

show abstract

“…On the other hand, it is likely that a low albumin-FA binding capacity is compensated by other acute phase plasma proteins with FA binding properties. To test if A1AT, a positive acute phase protein, is a FA binding protein, we employed an FA bead-based pull-down assay (26). When LA or OA-coupled beads were pre-incubated with A1AT-0 or HSA-0 (as a positive control), FA-coupled beads pulled down A1AT and HSA with similar efficiency.…”

Section: Discussionmentioning

confidence: 99%

“…Coupling of fatty acid to agarose beads was performed according to Beck-Garcia et al (26). Shortly, in a first step the carboxyl group of the fatty acid was activated by incubation of 46 μmol of fatty acid with 92 μmol of N,N-diisopropyl-ethylamine (DIEA) and 35 μmol O-(benzotriazol-1-yl)-tetramethylurnium tetrafluoroborate (TBTU) in 1 ml dimethylformamide (DMF) for 6 h at room temperature on a rotating mixer.…”

Section: Methodsmentioning

confidence: 99%

α1-Antitrypsin Combines with Plasma Fatty Acids and Induces Angiopoietin-like Protein 4 Expression

Frenzel

Wrenger

Brügger

et al. 2015

The Journal of Immunology

View full text Add to dashboard Cite

α1-Antitrypsin (A1AT) purified from human plasma upregulates expression and release of angiopoietin-like protein 4 (Angptl4) in adherent human blood monocytes and in human lung microvascular endothelial cells, providing a mechanism for the broad immune-regulatory properties of A1AT independent of its anti-protease activity. Here we demonstrate that A1AT (Prolastin®), a potent inducer of Angptl4, contains significant quantities of the fatty acids (FA): linoleic (LA, C18:2) and oleic (OA, C18:1). However, only trace amounts of FAs were present in preparations that failed to increase Angplt4 expression, for example A1AT (Zemaira) or M-type A1AT purified by affinity chromatography. FA pull-down assays with western blot analysis revealed a FA-binding ability of A1AT. In human blood adherent monocytes A1AT‐FA conjugates up-regulated expression of Angptl4 (54.9-fold, p<0.001), fatty acid binding protein 4 (FABP4) (11.4-fold, p<0.001) and to a lesser degree, fatty acid translocase (CD36) (3.1-fold, p<0.001) relative to A1AT devoid of FA (A1AT‐0). These latter effects of A1AT-FA were blocked by inhibitors of PPARβ/δ (ST247) and PPARγ (GW9662). When compared to controls, cell pre-treatment with ST247 diminished the effect of A1AT-LA on Angptl4 mRNA (11.6- vs 4.1-fold, p<0.001) and FABP4 mRNA (5.4-vs 2.8-fold, p<0.001). Similarly, pre-incubation of cells with GW9662 inhibited inducing effect of A1AT-LA on Angptl4 mRNA (by 2-fold, p<0.001) and FABP4 mRNA (by 3-fold, p<0.001). Thus, A1AT binds to FA, and it is this form of A1AT that induces Angptl4 and FABP4 expression via a PPARs-dependent pathway. These findings provide a mechanism for the unexplored area of A1AT biology independent of its anti-protease properties.

show abstract

Analysis of interactions between proteins and fatty acids or cholesterol using a fatty acid/cholesterol pull-down assay

Cited by 11 publications

References 18 publications

Inhibition of T cell receptor signaling by cholesterol sulfate, a naturally occurring derivative of membrane cholesterol

Inhibition of T cell receptor signaling by cholesterol sulfate, a naturally occurring derivative of membrane cholesterol

Sensory and chemical properties of peanut grains (Arachis hypogaea L) roasted in microwave or oven

α1-Antitrypsin Combines with Plasma Fatty Acids and Induces Angiopoietin-like Protein 4 Expression

Contact Info

Product

Resources

About