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Molecular & Cellular Proteomics : MCP Dec 2023Proteins can be modified by lipids in various ways, for example, by myristoylation, palmitoylation, farnesylation, and geranylgeranylation-these processes are...
Proteins can be modified by lipids in various ways, for example, by myristoylation, palmitoylation, farnesylation, and geranylgeranylation-these processes are collectively referred to as lipidation. Current chemical proteomics using alkyne lipids has enabled the identification of lipidated protein candidates but does not identify endogenous lipidation sites and is not readily applicable to in vivo systems. Here, we introduce a proteomic methodology for global analysis of endogenous protein N-terminal myristoylation sites that combines liquid-liquid extraction of hydrophobic lipidated peptides with liquid chromatography-tandem mass spectrometry using a gradient program of acetonitrile in the high concentration range. We applied this method to explore myristoylation sites in HeLa cells and identified a total of 75 protein N-terminal myristoylation sites, which is more than the number of high-confidence myristoylated proteins identified by myristic acid analog-based chemical proteomics. Isolation of myristoylated peptides from HeLa digests prepared with different proteases enabled the identification of different myristoylated sites, extending the coverage of N-myristoylome. Finally, we analyzed in vivo myristoylation sites in mouse tissues and found that the lipidation profile is tissue-specific. This simple method (not requiring chemical labeling or affinity purification) should be a promising tool for global profiling of protein N-terminal myristoylation.
Topics: Humans; Animals; Mice; Myristic Acid; HeLa Cells; Proteomics; Proteins; Peptides; Liquid-Liquid Extraction; Protein Processing, Post-Translational
PubMed: 37949301
DOI: 10.1016/j.mcpro.2023.100677 -
Communications Biology Jan 2022Arbuscular mycorrhizal (AM) symbiosis is a mutually beneficial interaction between fungi and land plants and promotes global phosphate cycling in terrestrial ecosystems....
Arbuscular mycorrhizal (AM) symbiosis is a mutually beneficial interaction between fungi and land plants and promotes global phosphate cycling in terrestrial ecosystems. AM fungi are recognised as obligate symbionts that require root colonisation to complete a life cycle involving the production of propagules, asexual spores. Recently, it has been shown that Rhizophagus irregularis can produce infection-competent secondary spores asymbiotically by adding a fatty acid, palmitoleic acid. Furthermore, asymbiotic growth can be supported using myristate as a carbon and energy source for their asymbiotic growth to increase fungal biomass. However, the spore production and the ability of these spores to colonise host roots were still limited compared to the co-culture of the fungus with plant roots. Here we show that a combination of two plant hormones, strigolactone and jasmonate, induces the production of a large number of infection-competent spores in asymbiotic cultures of Rhizophagus clarus HR1 in the presence of myristate and organic nitrogen. Inoculation of asymbiotically-generated spores promoted the growth of host plants, as observed for spores produced by symbiotic culture system. Our findings provide a foundation for the elucidation of hormonal control of the fungal life cycle and the development of inoculum production schemes.
Topics: Cyclopentanes; Fungi; Heterocyclic Compounds, 3-Ring; Lactones; Mycorrhizae; Myristic Acid; Nitrogen; Oxylipins; Plant Growth Regulators; Symbiosis
PubMed: 35022540
DOI: 10.1038/s42003-021-02967-5 -
Molecules (Basel, Switzerland) Aug 2019Supramolecular amino acid and peptide hydrogels are functional materials with a wide range of applications, however, their ability to serve as matrices for enzyme...
Supramolecular amino acid and peptide hydrogels are functional materials with a wide range of applications, however, their ability to serve as matrices for enzyme entrapment have been rarely explored. Two amino acid conjugates were synthesized and explored for hydrogel formation. These hydrogels were characterized in terms of strength and morphology, and their ability to entrap enzymes while keeping them active and reusable was explored. It was found that the hydrogels were able to successfully entrap two common and significant enzymes-horseradish peroxidase and -amylase-thus keeping them active and stable, along with inducing recycling capabilities, which has potential to further advance the industrial biotransformation field.
Topics: Amino Acids; Enzymes, Immobilized; Hydrogels; Myristic Acid; Phenylalanine; Spectrum Analysis; Surface-Active Agents
PubMed: 31398913
DOI: 10.3390/molecules24162884 -
Plant Physiology Feb 2014Some plants produce methylketones as potent defense compounds against various insects. Wild tomato (Solanum habrochaites), a relative of the cultivated tomato (Solanum...
Some plants produce methylketones as potent defense compounds against various insects. Wild tomato (Solanum habrochaites), a relative of the cultivated tomato (Solanum lycopersicum), synthesizes large amounts of 2-methylketones in its glandular trichomes, but cultivated tomato trichomes contain little or no methylketones. Two enzymes, Solanum habrochaites methylketone synthase1 (ShMKS1) and ShMKS2, are required to convert β-ketoacyl acyl-carrier protein intermediates of the fatty acid biosynthetic pathway to methylketones. ShMKS2 is a thioesterase that hydrolyzes β-ketoacyl acyl-carrier protein, and ShMKS1 is a decarboxylase that converts the resulting 3-ketoacids to 2-methylketones. We introduced ShMKS2 by itself or together with ShMKS1 to Arabidopsis (Arabidopsis thaliana), tobacco (Nicotiana tabacum), and cultivated tomato under the control of the 35S, Rubisco small subunit, and tomato trichome-specific promoters. Young tobacco and Arabidopsis plants expressing both genes under the control of 35S and Rubisco small subunit promoters produced methylketones in their leaves but had serious growth defects. As plants matured, they ceased to produce methylketones. Tobacco plants but not Arabidopsis or tomato plants expressing only ShMKS2 under the 35S promoter also synthesized methylketones, but at a lower rate. Transgenic cultivated tomato plants expressing ShMKS1 and ShMKS2 under trichome-specific promoters had slightly elevated levels of methylketone. Trace amounts of myristic acid were also detected in transgenic plants constitutively expressing ShMKS2 with or without ShMKS1. These results suggest that increases in methylketone production in plants will require the targeting of the pathway to self-contained structures in the plant and may also require increasing the flux of fatty acid biosynthesis.
Topics: Arabidopsis; Carboxy-Lyases; Gas Chromatography-Mass Spectrometry; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Ketones; Myristic Acid; Phenotype; Plant Leaves; Plant Proteins; Plants, Genetically Modified; Solanum; Nicotiana; Trichomes; Volatile Organic Compounds
PubMed: 24390393
DOI: 10.1104/pp.113.228502 -
BioMed Research International 2014A mixture of eight fatty acids (linoleic, palmitic, stearic, myristic, elaidic, lauric, oleic, and palmitoleic acids) at similar concentrations identified in human...
A mixture of eight fatty acids (linoleic, palmitic, stearic, myristic, elaidic, lauric, oleic, and palmitoleic acids) at similar concentrations identified in human amniotic fluid produces anxiolytic-like effects comparable to diazepam in Wistar rats. However, individual effects of each fatty acid remain unexplored. In Wistar rats, we evaluated the separate action of each fatty acid at the corresponding concentrations previously found in human amniotic fluid on anxiety-like behaviour. Individual effects were compared with vehicle, an artificial mixture of the same eight fatty acids, and a reference anxiolytic drug (diazepam, 2 mg/kg). Myristic acid, the fatty acid mixture, and diazepam increased the time spent in the open arms of the elevated plus maze and reduced the anxiety index compared with vehicle, without altering general locomotor activity. The other fatty acids had no effect on anxiety-like behaviour, but oleic acid reduced locomotor activity. Additionally, myristic acid produced anxiolytic-like effects only when the concentration corresponded to the one identified in human amniotic fluid (30 μg/mL) but did not alter locomotor activity. We conclude that of the eight fatty acids contained in the fatty acid mixture, only myristic acid produces anxiolytic-like effects when administered individually at a similar concentration detected in human amniotic fluid.
Topics: Amniotic Fluid; Animals; Anti-Anxiety Agents; Anxiety; Dose-Response Relationship, Drug; Fatty Acids; Humans; Male; Maze Learning; Myristic Acid; Rats; Rats, Wistar; Treatment Outcome
PubMed: 25328885
DOI: 10.1155/2014/492141 -
Journal of Dairy Science Apr 2007The objective of this study was to evaluate the effects of supplementing myristic acid in dairy cow rations on ruminal methanogenesis and the fatty acid profile in milk....
The objective of this study was to evaluate the effects of supplementing myristic acid in dairy cow rations on ruminal methanogenesis and the fatty acid profile in milk. Twelve multiparous Holstein dairy cows (710 +/- 17.3 kg of live weight; 290 +/- 41.9 d in milk) housed in a tie-stall facility were used in the study. The cows were paired by parity and days in milk and allocated to 1 of 2 treatments: 1) the regular milking cow total mixed ration (control diet), and 2) the regular milking cow total mixed ration supplemented with 5% myristic acid on a dry matter basis (MA diet). The cows were fed and milked twice daily (feeding, 0830 and 1300 h; milking, 0500 and 1500 h). The experiment was conducted as a completely randomized design and consisted of a 7-d pretrial period when cows were fed the control diet to obtain baseline measurements, a 10-d dietary adaptation period, and a 1-d, 8-h measurement period. The MA diet reduced methane (CH4) production by 36% (608.2 vs. 390.6 +/- 56.46 L/d, control vs. MA diet, respectively) and milk fat percentage by 2.4% (4.2 vs. 4.1 +/- 0.006%, control vs. MA diet, respectively). The MA diet increased 14:0 in milk by 139% and cis-9 14:1 by 195%. There was a correlation (r = -0.58) between the 14:0 content in milk and CH4 production and cis-9 14:1 and CH4 production (r = -0.47). Myristic acid had no effect on the contents of CLA or trans-10 18:1 and trans-11 18:1 isomers in milk. These results suggest that MA could be used to inhibit the activities of methanogens in ruminant animals without altering the conjugated linoleic acid and trans-18:1 fatty acid profile in milk.
Topics: Animal Feed; Animals; Cattle; Dairying; Dietary Supplements; Eating; Fatty Acids; Female; Lactation; Methane; Milk; Milk Proteins; Myristic Acid; Rumen
PubMed: 17369226
DOI: 10.3168/jds.2006-541 -
Journal of Applied Physiology... Aug 2011Surfactant predominantly comprises phosphatidylcholine (PC) species, together with phosphatidylglycerols, phosphatidylinositols, neutral lipids, and surfactant...
Surfactant predominantly comprises phosphatidylcholine (PC) species, together with phosphatidylglycerols, phosphatidylinositols, neutral lipids, and surfactant proteins-A to -D. Together, dipalmitoyl-PC (PC16:0/16:0), palmitoyl-myristoyl-PC (PC16:0/14:0), and palmitoyl-palmitoleoyl-PC (PC16:0/16:1) make up 75-80% of mammalian surfactant PC, the proportions of which vary during development and in chronic lung diseases. PC16:0/14:0, which exerts specific effects on macrophage differentiation in vitro, increases in surfactant during alveolarization (at the expense of PC16:0/16:0), a prenatal event in humans but postnatal in rats. The mechanisms responsible and the significance of this reversible increase are, however, not understood. We hypothesized that, in rats, myristic acid (C14:0) enriched milk is key to lung-specific PC16:0/14:0 increases in surfactant. We found that surfactant PC16:0/14:0 in suckling rats correlates with C14:0 concentration in plasma chylomicrons and lung tissue triglycerides, and that PC16:0/14:0 fractions reflect exogenous C14:0 supply. Significantly, C14:0 was increased neither in plasma PC, nor in liver triglycerides, free fatty acids, or PC. Lauric acid was also abundant in triglycerides, but was not incorporated into surfactant PC. Comparing a C14:0-rich milk diet with a C14:0-poor carbohydrate diet revealed increased C14:0 and decreased C16:0 in plasma and lung triglycerides, respectively. PC16:0/14:0 enrichment at the expense of PC16:0/16:0 did not impair surfactant surface tension function. However, the PC profile of the alveolar macrophages from the milk-fed animals changed from PC16:0/16:0 rich to PC16:0/14:0 rich. This was accompanied by reduced reactive oxygen species production. We propose that nutritional supply with C14:0 and its lung-specific enrichment may contribute to decreased reactive oxygen species production during alveolarization.
Topics: Animals; Animals, Newborn; Diet; Fatty Acids, Nonesterified; Gastrointestinal Contents; Lipid Metabolism; Lipoproteins; Liver; Lung; Milk; Myristic Acid; Phosphatidylcholines; Pulmonary Alveoli; Pulmonary Surfactants; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Triglycerides
PubMed: 21636561
DOI: 10.1152/japplphysiol.00766.2010 -
The Journal of Biological Chemistry Jul 1991Because myristic acid (14:0) is important in regulating cell function, we have studied its utilization in BC3H1 muscle cells. Phosphatidylcholine contained 70-80% of the...
Because myristic acid (14:0) is important in regulating cell function, we have studied its utilization in BC3H1 muscle cells. Phosphatidylcholine contained 70-80% of the [9,10-3H]14:0 radioactivity incorporated into the cell phospholipids. In both myoblasts and myocytes, however, large amounts of radioactivity also accumulated in a labile neutral lipid pool consisting mostly of triacylglycerol. Therefore, radioactive lipid products formed when BC3H1 cells labeled with 14:0 are stimulated are not necessarily derived only from phosphatidylcholine. Elongation of [9,10-3H]14:0 occurred rapidly in the myoblasts and myocytes, and extensive desaturation also occurred in the myoblasts. Thus, even after short periods of labeling, substantial amounts of radioactivity are contained in fatty acids other than 14:0. The labeling of proteins with [9,10-3H]myristic acid was generally similar in the myoblasts and myocytes. A number of lipid-soluble, polar radioactive metabolites were released into the medium during incubation of [9,10-3H]14:0 with the cells. [1-14C] 14:0 was not converted to these compounds, indicating that they are chain-shortened 14:0 derivatives. Based on chemical analysis, two of the major products appear to be hydroxylated fatty acids. This oxidation process shows some specificity for 14:0 because similar compounds were not produced from palmitic, oleic, or linoleic acids. The myocytes formed larger amounts of the metabolites than the myoblasts, suggesting that differentiation may increase the activity of this 14:0 oxidative pathway.
Topics: Acylation; Animals; Biological Transport; Cell Line; Fatty Acids; In Vitro Techniques; Lipid Metabolism; Mice; Muscle Proteins; Muscles; Myristic Acid; Myristic Acids
PubMed: 1856220
DOI: No ID Found -
Methods in Enzymology 2023N-terminal myristoylation is an essential eukaryotic modification crucial for cellular homeostasis in the context of many physiological processes. Myristoylation is a...
N-terminal myristoylation is an essential eukaryotic modification crucial for cellular homeostasis in the context of many physiological processes. Myristoylation is a lipid modification resulting in a C14 saturated fatty acid addition. This modification is challenging to capture due to its hydrophobicity, low abundance of target substrates, and the recent discovery of unexpected NMT reactivity including myristoylation of lysine side chains and N-acetylation in addition to classical N-terminal Gly-myristoylation. This chapter details the high-end approaches developed to characterize the different features of N-myristoylation and its targets through in vitro and in vivo labeling.
Topics: Acyltransferases; Myristic Acid; Fatty Acids; Lysine
PubMed: 37230587
DOI: 10.1016/bs.mie.2023.02.016 -
Chemical & Pharmaceutical Bulletin 2012The bactericidal properties of myristic acid and curcumin were revealed in a number of studies. However, whether curcumin-loaded myristic acid microemulsions can be used...
The bactericidal properties of myristic acid and curcumin were revealed in a number of studies. However, whether curcumin-loaded myristic acid microemulsions can be used to inhibit Staphylococcus epidermidis, which causes nosocomial infections, has not been reported. Our aim was to develop curcumin-loaded myristic acid microemulsions to inhibit S. epidermidis on the skin. The interfacial tension, size distribution, and viscosity data of the microemulsions were characterized to elucidate the physicochemical properties of the curcumin microemulsions. Curcumin distribution in neonate pig skin was visualized using confocal laser scanning microscopy. Dermal curcumin accumulation (326 µg/g skin) and transdermal curcumin penetration (87 µg/cm(2)/d) were obtained with the microemulsions developed herein. Curcumin at the concentration of 0.86 µg/mL in the myristic acid microemulsion could inhibit 50% of the bacterial growth, which was 12 times more effective than curcumin dissolved in dimethyl sulfoxide (DMSO). The cocktail combination of myristic acid and curcumin in the microemulsion carrier synergistically inhibited the growth of S. epidermidis. The results we obtained highlight the potential of using curcumin-loaded microemulsions as an alternative treatment for S. epidermidis-associated diseases and acne vulgaris.
Topics: Administration, Topical; Animals; Anti-Bacterial Agents; Cross Infection; Curcumin; Emulsions; Humans; Myristic Acid; Skin; Skin Absorption; Staphylococcal Infections; Staphylococcus epidermidis; Swine
PubMed: 22976319
DOI: 10.1248/cpb.c12-00220