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https://www.readbyqxmd.com/read/29156157/continuous-gradient-temperature-raman-spectroscopy-from-100-to-40%C3%A2-c-yields-new-molecular-models-of-arachidonic-acid-and-2-arachidonoyl-1-stearoyl-sn-glycero-3-phosphocholine
#1
C Leigh Broadhurst, Walter F Schmidt, Julie K Nguyen, Jianwei Qin, Kuanglin Chao, Moon S Kim
Despite its biochemical importance, a complete Raman analysis of arachidonic acid (AA, 20:4n-6) has never been reported. Gradient temperature Raman spectroscopy (GTRS) applies the temperature gradients utilized in differential scanning calorimetry (DSC) to Raman spectroscopy, providing a straightforward technique to identify molecular rearrangements that occur near and at phase transitions. Herein we utilize the GTRS technique for AA and 1-18:0, 2-20:4n-6 phosphatidyl choline (AAPC) from cryogenic to mammalian body temperatures...
December 2017: Prostaglandins, Leukotrienes, and Essential Fatty Acids
https://www.readbyqxmd.com/read/29145606/-prokaryotic-pathway-is-not-prokaryotic-non-cyanobacterial-origin-of-the-chloroplast-lipid-biosynthetic-pathway-revealed-by-comprehensive-phylogenomic-analysis
#2
Naoki Sato, Koichiro Awai
Lipid biosynthesis within the chloroplast, or more generally plastids, was conventionally called "prokaryotic pathway", which produces glycerolipids bearing C18 acids at the sn-1 position and C16 acids at the sn-2 position, as in cyanobacteria such as Anabaena and Synechocystis. This positional specificity is determined during the synthesis of phosphatidate, which is a precursor to diacylglycerol, the acceptor of galactose for the synthesis of galactolipids. The first acylation at sn-1 is catalyzed by glycerol-3-phosphate acyltransferase (GPAT or GPT), whereas the second acylation at sn-2 is performed by lysophosphatidate acyltransferase (LPAAT, AGPAT or PlsC)...
November 14, 2017: Genome Biology and Evolution
https://www.readbyqxmd.com/read/29136584/unprecedented-chemosensing-behavior-of-novel-tetra-substituted-benzimidazole-zinc-ii-phthalocynine-for-selective-detection-of-bi-3-ion-synthesis-characterization-and-ros-generation
#3
Azeem Ullah, Faheem Shah, Imran Khan, Muhammad Anwar, Kiramat Shah, Munira Taj Muhammad, Farid Ahmad
In this work, synthesis of novel symmetrical 4-(2-bromo-4-(5-bromo-1H-benzo[d] imidazol-2-yl) phenoxy) tetra substituted zinc phthalocyanine has been reported. The novel benzimidazole zinc phthlocynine compound (3) has been characterized by MALDI-TOF MS, FT-IR, UV-vis, and (1)H NMR spectroscopy. This new compound 3 displayed excellent selectivity towards Bi(3+) ion in the presence of other competitive ions including Ca(2+), Cd(2+), Co(2+) Cu(2+), Fe(3+), Hg(2+), Sn(2+), Mg(2+), Na(+), Ni(2+) and Pb(2+) respectively...
November 10, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/29130691/insertion-of-a-transient-tin-nitride-into-carbon-carbon-and-boron-carbon-bonds
#4
Shuai Wang, Lizhi Tao, Troy A Stich, Marilyn M Olmstead, R David Britt, Philip P Power
A simple exchange reaction between [Ar(iPr4)Sn(μ-Cl)]2 (1) and sodium azide afforded the doubly bridged Sn(II) azide, [Ar(iPr4)Sn(μ-N3)]2 (2) (Ar(iPr4) = C6H3-2,6(C6H3-2,6-(i)Pr2)2) in 85% yield. Photolysis of a diethyl ether solution of 2 for ca. 16 h yielded an azepinyl-substituted insertion product, [C6H3-2-(C6H3-2,6-(i)Pr2)-6-(C6H3N-3,7-(i)Pr2)Sn]2 (3). The reaction of the Lewis acid, B(C6F5)3 (BCF), or the Lewis base, pyridine, with 2 dissociates the dimer to afford the corresponding complexed monomeric Sn(II) azide, Ar(iPr4)SnN3BCF (4) in which BCF coordinates the α-nitrogen, or Ar(iPr4)Sn(pyridine)N3 (6) in which pyridine coordinates to the tin atom...
November 13, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29129896/extraction-and-the-fatty-acid-profile-ofrosa-acicularis-seed-oil
#5
Huanan Du, Xu Zhang, Ruchun Zhang, Lu Zhang, Dianyu Yu, Lianzhou Jiang
Rosa acicularis seed oil was extracted from Rosa acicularis seeds by the ultrasonic-assisted aqueous enzymatic method using cellulase and protease. Based on a single experiment, Plackett-Burman design was applied to ultrasonic-assisted aqueous enzymatic extraction of wild rose seed oil. The effects of enzyme amount, hydrolysis temperature and initial pH on total extraction rate of wild rose seed oil was studied by using Box-Behnken optimize methodology. Chemical characteristics of a sample of Rosa acicularis seeds and Rosa acicularis seed oil were characterized in this work...
November 13, 2017: Journal of Oleo Science
https://www.readbyqxmd.com/read/29129849/lipoquality-control-by-phospholipase-a2-enzymes
#6
Makoto Murakami
The phospholipase A2 (PLA2) family comprises a group of lipolytic enzymes that typically hydrolyze the sn-2 position of glycerophospholipids to give rise to fatty acids and lysophospholipids. The mammalian genome encodes more than 50 PLA2s or related enzymes, which are classified into several subfamilies on the basis of their structures and functions. From a general viewpoint, the PLA2 family has mainly been implicated in signal transduction, producing bioactive lipid mediators derived from fatty acids and lysophospholipids...
2017: Proceedings of the Japan Academy. Series B, Physical and Biological Sciences
https://www.readbyqxmd.com/read/29125196/an-interacting-quantum-atom-study-of-model-sn-2-reactions-x-%C3%A2-%C3%A2-%C3%A2-ch3-x-x%C3%A2-%C3%A2-f-cl-br-and-i
#7
Ibon Alkorta, Joseph C R Thacker, Paul L A Popelier
The quantum chemical topology method has been used to analyze the energetic profiles in the X(-)  + CH3 X → XCH3  + X(-) SN 2 reactions, with X = F, Cl, Br, and I. The evolution of the electron density properties at the BCPs along the reaction coordinate has been analysed. The interacting quantum atoms (IQA) method has been used to evaluate the intra-atomic and interatomic energy variations along the reaction path. The different energetic terms have been examined by the relative energy gradient method and the ANANKE program, which enables automatic and unbiased IQA analysis...
November 10, 2017: Journal of Computational Chemistry
https://www.readbyqxmd.com/read/29120186/constrained-vs-free-cholesterol-in-dppc-membranes-a-comparison-of-chain-ordering-ability-using-deuterium-nmr
#8
Mehran Shaghaghi, Amir Keyvanloo, Zhaohua Huang, Francis C Szoka, Jenifer L Thewalt
We report here the first exploration of the nature of the hydrophobic region of bilayer membranes formed from sterol modified phospholipids [Huang, Z.; Szoka, F. C., Sterol-Modified Phospholipids: Cholesterol and Phospholipid Chimeras with Improved Biomembrane Properties. J. Am. Chem. Soc. 2008, 130 (46), 15702-15712] & [Ding, J.; Starling, A. P.; East, J.M.; Lee, A. G., Binding Sites for Cholesterol on Ca(2+)-ATPase Studied by using a Cholesterol-containing Phospholipid. Biochemistry. 1994, 33(16), 4974-4979]...
November 9, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/29117232/rate-of-acyl-migration-in-lysophosphatidylcholine-lpc-is-dependent-upon-the-nature-of-the-acyl-group-greater-stability-of-sn-2-docosahexaenoyl-lpc-compared-to-the-more-saturated-lpc-species
#9
Dhavamani Sugasini, Papasani V Subbaiah
Several previous studies reported that sn-2 acyl lysophosphatidylcholines (LPCs) undergo rapid isomerization due to acyl migration, especially at physiological pH and temperature. However, these studies have been carried out using mostly sn-2 palmitoyl LPC, whereas the naturally occurring sn-2 LPCs are predominantly unsaturated. In this study, we investigated the acyl migration in four naturally occurring sn-2 acyl LPCs (sn-2 16:0, sn-2 18:1, sn-2 20:4, and sn-2 22:6) stored at various temperatures in aqueous or organic solvents, employing LC/MS to analyze the isomer composition...
2017: PloS One
https://www.readbyqxmd.com/read/29101519/computational-modeling-and-in-vitro-in-silico-correlation-of-phospholipid-based-prodrugs-for-targeted-drug-delivery-in-inflammatory-bowel-disease
#10
Arik Dahan, Milica Markovic, Shahar Keinan, Igor Kurnikov, Aaron Aponick, Ellen M Zimmermann, Shimon Ben-Shabat
Targeting drugs to the inflamed intestinal tissue(s) represents a major advancement in the treatment of inflammatory bowel disease (IBD). In this work we present a powerful in-silico modeling approach to guide the molecular design of novel prodrugs targeting the enzyme PLA2, which is overexpressed in the inflamed tissues of IBD patients. The prodrug consists of the drug moiety bound to the sn-2 position of phospholipid (PL) through a carbonic linker, aiming to allow PLA2 to release the free drug. The linker length dictates the affinity of the PL-drug conjugate to PLA2, and the optimal linker will enable maximal PLA2-mediated activation...
November 3, 2017: Journal of Computer-aided Molecular Design
https://www.readbyqxmd.com/read/29093377/recovery-and-utilization-of-palm-oil-mill-effluent-source-as-value-added-food-products
#11
Soek Sin Teh, Augustine Soon Hock Ong, Siau Hui Mah
The environmental impacts of palm oil mill effluent (POME) have been a concern due to the water pollution and greenhouse gases emissions. Thus, this study was conducted to recover the value-added products from POME source before being discharged. The samples, before (X) and after (Y) the pre-recovery system in the clarification tank were sampled and analysed and proximate analysis indicated that both samples are energy rich source of food due to high contents of fats and carbohydrates. GCMS analysis showed that the oil extracts contain predominantly palmitic, oleic, linoleic and stearic acids...
2017: Journal of Oleo Science
https://www.readbyqxmd.com/read/29091407/role-of-acyl-chain-composition-of-phosphatidylcholine-in-tafazzin-mediated-remodeling-of-cardiolipin-in-liposomes
#12
Masato Abe, Yoshiki Sawada, Shinpei Uno, Shuhei Chigasaki, Masahide Oku, Yasuyoshi Sakai, Hideto Miyoshi
Remodeling of the acyl chain compositions of cardiolipin (CL) species by the transacylase tafazzin is an important process for maintaining optimal mitochondrial functions. The results of mechanistic studies on the tafazzin-mediated transacylation from phosphatidylcholine (PC) to monolyso-CL (MLCL) in artificial lipid membranes are controversial. The present study investigated the role of the acyl chain composition of PC in the Saccharomyces cerevisiae tafazzin-mediated remodeling of CL by examining the structural factors responsible for the superior acyl donor ability of dipalmitoleoyl (16:1) PC over dipalmitoyl (16:0) PC...
November 9, 2017: Biochemistry
https://www.readbyqxmd.com/read/29064240/structural-evolution-in-basn2f5x-x-cl-br-i-a-family-of-alkaline-earth-metal-tin-mixed-halides
#13
Zheshuai Lin, Pifu Gong, Yi Yang, Siyang Luo, Fei Liang, Xingxing Jiang
As the first family of Sn-based alkaline earth metal mixed halides, three new compounds, BaSn2F5X (X = Cl, Br, and I), are synthesized by hydrothermal method. These compounds are crystallized in the centrosymmetric space groups of P21/c, P4/nmm, and Pmma for BaSn2F5Cl, BaSn2F5Br, and BaSn2F5I, respectively, and their microscopic frameworks are all composed of the fundamental structural unit [SnF4](2-) and its derivatives ([SnF4Cl](3-) and [SnF5](3-) groups). Interestingly, the structures in BaSn2F5X are significantly changed from one-dimensional (1D) to two-dimensional (2D) and then to 1D motifs as X varies from Cl, Br, to I...
November 6, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29037692/evaluation-of-sn-2-fatty-acid-composition-in-commercial-infant-formulas-on-the-chinese-market-a-comparative-study-based-on-fat-source-and-stage
#14
Cong Sun, Wei Wei, Hang Su, Xiaoqiang Zou, Xingguo Wang
The sn-2 fatty acid composition of 180 commercial infant, follow-on and growing-up formulas with three fat sources (plant oil, cows' milk and goats' milk) was investigated and compared with mature human milk (MHM). Sn-2 fatty acids in formulas were mostly dependent on fat source and stage. Compared with MHM, all types of formulas contained lower levels of palmitic acid (PA), saturated fatty acid and long-chain polyunsaturated fatty acids (LC-PUFA), and higher levels of oleic acid (OA), linoleic acid (LA) and α-linolenic acid (LNA) at the sn-2 position...
March 1, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29028022/continuous-tunable-broadband-emission-of-fluorphosphate-glasses-for-single-component-multi-chromatic-phosphors
#15
Ruilin Zheng, Qi Zhang, Kehan Yu, Chunxiao Liu, Jianyong Ding, Peng Lv, Wei Wei
A kind of Sn(2+)/Mn(2+) co-doped fluorphosphate (FP) glasses that served as single-component continuous tunable broadband emitting multi-chromatic phosphors are developed for the first time. Importantly, these FP glasses have high thermal conductivity (3.25-3.70  W/m·K) and good chemical stability in water (80°C). By combining with commercially available UV-LEDs directly, the emission colors can be tuned from blue/cold-white to warm-white/red through the energy transfer from Sn(2+) to Mn(2+), and the broadband spectra covering the whole visible region from 380 nm to 760 nm...
October 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/29023569/pancreatic-and-snake-venom-presynaptically-active-phospholipases-a2-inhibit-nicotinic-acetylcholine-receptors
#16
Catherine A Vulfius, Igor E Kasheverov, Elena V Kryukova, Ekaterina N Spirova, Irina V Shelukhina, Vladislav G Starkov, Tatyana V Andreeva, Grazyna Faure, Marios Zouridakis, Victor I Tsetlin, Yuri N Utkin
Phospholipases A2 (PLA2s) are enzymes found throughout the animal kingdom. They hydrolyze phospholipids in the sn-2 position producing lysophospholipids and unsaturated fatty acids, agents that can damage membranes. PLA2s from snake venoms have numerous toxic effects, not all of which can be explained by phospholipid hydrolysis, and each enzyme has a specific effect. We have earlier demonstrated the capability of several snake venom PLA2s with different enzymatic, cytotoxic, anticoagulant and antiproliferative properties, to decrease acetylcholine-induced currents in Lymnaea stagnalis neurons, and to compete with α-bungarotoxin for binding to nicotinic acetylcholine receptors (nAChRs) and acetylcholine binding protein...
2017: PloS One
https://www.readbyqxmd.com/read/29021496/comparison-of-the-distribution-of-unsaturated-fatty-acids-at-the-sn-2-position-of-phospholipids-and-triacylglycerols-in-marine-fishes-and-mammals
#17
Fumiaki Beppu, Keiko Yasuda, Ayako Okada, Yoshitsugu Hirosaki, Masako Okazaki, Naohiro Gotoh
Highly unsaturated fatty acid (HUFA) binding at the sn-2 position of phospholipids (PL) becomes a resource for prostaglandin, leukotriene, resolvin, and protectin synthesis. Both triacylglycerol (TAG) and PL synthesis pathways in vivo are via phosphatidic acid; therefore, the distribution of fatty acid species at the sn-2 position must theoretically be the same for TAG and PL if rearrangement does not occur. However, it is known that little HUFA is located at the sn-2 position of TAG in marine mammals. Therefore, distribution of fatty acid species at the sn-2 position of TAG and PL was compared between marine fishes and mammals in this study...
October 11, 2017: Journal of Oleo Science
https://www.readbyqxmd.com/read/28992041/peripheral-tissue-levels-and-molecular-species-compositions-of-n-acyl-phosphatidylethanolamine-and-its-metabolites-in-mice-lacking-n-acyl-phosphatidylethanolamine-specific-phospholipase-d
#18
Manami Inoue, Kazuhito Tsuboi, Yoko Okamoto, Mayumi Hidaka, Toru Uyama, Toshihiko Tsutsumi, Tamotsu Tanaka, Natsuo Ueda, Akira Tokumura
N-acylethanolamines (NAEs), a class of lipid mediators, are produced from N-acyl-phosphatidylethanolamine (NAPE) by several pathways, including the direct release by NAPE-specific phospholipase D (NAPE-PLD) or the multistep pathway via sn-glycero-3-phospho-N-acylethanolamine (Gp-NAE). Using liquid chromatography-tandem mass spectrometry, we compared peripheral tissue levels of NAPE, Gp-NAE and NAE in NAPE-PLD-deficient (NAPE-PLD-/-) and wild type (WT) mice. NAPE-PLD was suggested to play a major role in the NAPE degradation in heart, kidney, and liver, but not in jejunum, because the NAPE levels except jejunum were significantly higher in NAPE-PLD-/- mice than in WT mice...
August 16, 2017: Journal of Biochemistry
https://www.readbyqxmd.com/read/28989600/chemical-tuning-of-dynamic-cation-off-centering-in-the-cubic-phases-of-hybrid-tin-and-lead-halide-perovskites
#19
Geneva Laurita, Douglas H Fabini, Constantinos C Stoumpos, Mercouri G Kanatzidis, Ram Seshadri
Hybrid halide perovskites combine ease of preparation and relatively abundant constituent elements with fascinating photophysical properties. Descriptions of the chemical and structural drivers of the remarkable properties have often focused on the potential role of the dynamic order/disorder of the molecular A-site cations. We reveal here a key aspect of the inorganic framework that potentially impacts the electronic, thermal, and dielectric properties. The temperature evolution of the X-ray pair distribution functions of hybrid perovskites ABX3 [A(+) = CH3NH3 (MA) or CH(NH2)2 (FA); B(2+) = Sn or Pb; X(-) = Br, or I] in their cubic phases above 300 K reveals temperature-activated displacement (off-centering) of the divalent group 14 cations from their nominal, centered sites...
August 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28973305/metabolic-reproductive-and-neurologic-abnormalities-in-agpat1-null-mice
#20
Anil K Agarwal, Katie Tunison, Jasbir S Dalal, Sneha S Nagamma, F Kent Hamra, Shireesha Sankella, Xinli Shao, Richard J Auchus, Abhimanyu Garg
Defects in the biosynthesis of phospholipids and neutral lipids are associated with cell membrane dysfunction, disrupted energy metabolism, and diseases including lipodystrophy. In these pathways, the 1-acylglycerol-3-phosphate O-acyltransferase (AGPAT) enzymes transfer a fatty acid to the sn-2 carbon of sn-1-acylglycerol-3-phosphate (lysophosphatidic acid) to form sn-1, 2-acylglycerol-3-phosphate [phosphatidic acid (PA)]. PA is a precursor for key phospholipids and diacylglycerol. AGPAT1 and AGPAT2 are highly homologous isoenzymes that are both expressed in adipocytes...
November 1, 2017: Endocrinology
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