Extrapolation of the Orthorhombicn‐Paraffin Melting Properties to Very Long Chain Lengths

1962 ◽  
Vol 36 (10) ◽  
pp. 2578-2582 ◽  
Author(s):  
Martin G. Broadhurst
Keyword(s):  
Melting Properties ◽  
Chain Lengths ◽  
Long Chain

The Use of N-alkanes for Estimating Intake and Passage Rate in Horses

1996 ◽  
Vol 1996 ◽  
pp. 98-98
Author(s):  
B M L McLean ◽  
R W Mayes ◽  
F D DeB Hovell
Keyword(s):  
Recent Work ◽  
Chain Length ◽  
Carbon Chain ◽  
Carbon Chain Length ◽  
Passage Rate ◽  
Forage Crops ◽  
Carbon Chains ◽  
Naturally Occurring ◽  
Chain Lengths ◽  
Long Chain

Alkanes occur naturally in all plants, although forage crops tend to have higher alkane contents than cereals. N-alkanes have odd-numbered carbon chains. They are ideal for use as markers in feed trials, because, they are inert, indigestible and naturally occurring, and can be recovered in animal faeces. Synthetic alkanes (even-numbered carbon chains) are available commercially and can also used as external markers. Dove and Mayes (1991) cite evidence indicating that faecal recovery of alkanes in ruminants increases with increasing carbon-chain length. Thus the alkane “pairs” (e.g. C35 & C36, and C32 & C33) are used in calculating intake and digestibility because they are long chain and adjacent to each other. However, recent work by Cuddeford and Mayes (unpublished) has found that in horses the faecal recovery rates are similar regardless of chain lengths.

Antibacterial Effects of Long-Chain Polyphosphates on Selected Spoilage and Pathogenic Bacteria

2008 ◽  
Vol 71 (7) ◽  
pp. 1401-1405 ◽  
Author(s):  
JEREMY A. OBRITSCH ◽  
DOJIN RYU ◽  
LUCINA E. LAMPILA ◽  
LLOYD B. BULLERMAN
Keyword(s):  
Food Industry ◽  
Pathogenic Bacteria ◽  
Antimicrobial Activities ◽  
Lag Phase ◽  
E Coli ◽  
Inhibition Of Growth ◽  
K 12 ◽  
Chain Lengths ◽  
And Staphylococcus Aureus ◽  
Long Chain

The antimicrobial activities of four long-chain food-grade polyphosphates were studied at concentrations allowed in the food industry (<5,000 ppm) in defined basal media by determining the inhibition of growth of three gram-negative and four gram-positive spoilage and pathogenic bacteria. Both generation time and lag phase of Escherichia coli K-12, E. coli O157: H7, and Salmonella Typhimurium were increased with all of the polyphosphates tested. Bacillus subtilis and Staphylococcus aureus were more sensitive to polyphosphates, but not in all cases, with multiphased growth. The growth of Lactobacillus plantarum was inhibited by polyphosphates at concentrations above 750 ppm, but the lag time of Listeria monocytogenes was shortened by the presence of polyphosphates. No single polyphosphate was maximally inhibitory against all bacteria. Polyphosphates with chain lengths of 12 to 15 were significantly different from those with chain lengths of 18 to 21 depending on the organism and concentrations of polyphosphate used. Overall, higher polyphosphate concentrations resulted in greater inhibition of bacterial growth.

scholarly journals Multiple mutagenesis of non-universal serine codons of the Candida rugosa LIP2 gene and biochemical characterization of purified recombinant LIP2 lipase overexpressed in Pichia pastoris

2002 ◽  
Vol 366 (2) ◽  
pp. 603-611 ◽  
Author(s):  
Guan-Chiun LEE ◽  
Li-Chiun LEE ◽  
Vasyl SAVA ◽  
Jei-Fu SHAW
Keyword(s):  
Pichia Pastoris ◽  
Biochemical Characterization ◽  
Candida Rugosa ◽  
Residual Activity ◽  
Site Directed Mutagenesis ◽  
Overlap Extension ◽  
Chain Lengths ◽  
Serine Codons ◽  
Long Chain ◽  
Lip2 Lipase

The 17 non-universal serine codons (CTG) in the Candida rugosa LIP2 gene have been converted into universal serine codons (TCT) by overlap extension PCR-based multiple site-directed mutagenesis. An active recombinant LIP2 lipase was overexpressed in Pichia pastoris and secreted into the culture medium. The recombinant LIP2 showed distinguishing catalytic activities when compared with recombinant LIP4 and commercial C. rugosa lipase. The purified enzyme showed optimum activity at pH7 and a broad temperature optimum in the range 30–50°C. The enzyme retained 80% of residual activity after being heated at 70°C for 10min. Recombinant LIP2 demonstrated high esterase activity towards long-chain (C12–C16) p-nitrophenyl esters. Tributyrin was the preferred substrate among all triacylglycerols tested for lipolysis. Among cholesteryl esters, LIP2 showed highest lipolytic activity towards cholesteryl laurate. The esterification of myristic acid with alcohols of various chain lengths showed that the long-chain n-octadecanol (C18) was the preferred substrate. In contrast, the esterification of n-propanol with fatty acids of various chain lengths showed that the short-chain butyric acid was the best substrate. From comparative modelling analysis, it appears that several amino acid substitutions resulting in greater hydrophobicity in the substrate-binding site might play an important role in the substrate specificity of LIP2.

Abstract 16607: Age-induced Endoplasmic Reticulum Stress in the Heart: Role of Increased Very Long-chain Ceramides

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Qun Chen ◽  
Anna Kovilakath ◽  
Jeremy Allegood ◽  
Lauren A Cowart ◽  
Edward J Lesnefsky
Keyword(s):  
Er Stress ◽  
Mitochondrial Dysfunction ◽  
Acyl Chain ◽  
Membrane Domains ◽  
Ceramide Synthase ◽  
Age Related ◽  
Chain Lengths ◽  
Endoplasm Reticulum ◽  
Long Chain

Introduction: Mitochondrial function is impaired in aged hearts. Increased endoplasm reticulum (ER) stress contributes to the mitochondrial dysfunction observed during aging. Ceramides (CRMD) are sphingolipid metabolites that contribute key roles in cell signaling. Increased CRMD can lead to ER stress. Ceramide synthase enzymes (CerS) generate chain length specific CRMD with the CerS isoform 2 (Cers2) forming very long chain CRMD of ≥ 20 carbon acyl chain lengths. Hypothesis: An increase in CRMD content during aging contributes to age-related ER stress. Methods: Male mice (3, 18, 24 mo.) from the NIA colony were studied. Cardiac mitochondria (MITO), mitochondrial associated membranes (MAM), and ER were isolated from mouse hearts. CRMD content was measured using LC-MS. The contents of CerS enzymes were measured by immunoblotting in myocardial homogenates. Results: ER stress increased progressively during aging with increased contents of cleaved ATF6 and CHOP, indicators of increased ER stress, evident at 18 and 24 mo. (Panel A) (all data mean±SEM; *p<0.05 vs. 3 mo., † p<0.05 vs. 18 mo.). Aging increased very long-chain CRMD (≥C20) in ER (Panel B) at 18 and 24 mo. Similar CRMD trends were observed MAM (Panel C), shared membrane domains where ER and MITO interact. The content of CerS2 was increased at 24 mo. compared to 3 mo. (Panel D, n=4 each age). In contrast, the contents of CerS isoforms 4 and 5, that generate shorter chain CRMD (<C20) were unchanged (not shown). CRMD contents in MITO were unaltered with age (not shown). Thus, increased generation of very long chain CRMD in the ER is the likely mechanism of increased ER stress in the aged heart. Conclusion: Aging increased ER CRMD content by enhancing the formation of very long chain CRMD in ER by an increase in CerS2 content, concomitant with the onset of ER stress. The increase in age-induced ER stress, in turn, leads to mitochondrial dysfunction in the aged heart.

scholarly journals The occurrence of polyenoic very long chain fatty acids with greater than 32 carbon atoms in molecular species of phosphatidylcholine in normal and peroxisome-deficient (Zellweger's syndrome) brain

1988 ◽  
Vol 253 (3) ◽  
pp. 645-650 ◽  
Author(s):  
A Poulos ◽  
P Sharp ◽  
D Johnson ◽  
C Easton
Keyword(s):  
Fatty Acids ◽  
Molecular Species ◽  
Carbon Chain ◽  
Normal Brain ◽  
Long Chain Fatty Acids ◽  
Brain Physiology ◽  
Chain Lengths ◽  
The Brain ◽  
Long Chain ◽  
Chain Fatty Acids

The n-6 tetra- and pentaenoic fatty acids with carbon chain lengths greater than 32 found in normal brain are located predominantly in a separable species of phosphatidylcholine. A similar phospholipid is found in increased amounts in the brain of peroxisome-deficient (Zellweger's syndrome) patients, but the fatty acid composition differs in that penta- and hexaenoic derivatives predominate. Our data strongly suggest that the polyenoic very long chain fatty acids are confined to the sn-1 position of the glycerol moiety, while the sn-2 position is enriched in saturated, monounsaturated and polyunsaturated fatty acids with less than 24 carbon atoms. It is postulated that these unusual molecular species of phosphatidylcholine may play some, as yet undefined, role in brain physiology.

scholarly journals Elevation of 20-carbon long chain bases due to a mutation in serine palmitoyltransferase small subunit b results in neurodegeneration

2015 ◽  
Vol 112 (42) ◽  
pp. 12962-12967 ◽  
Author(s):  
Lihong Zhao ◽  
Stefka Spassieva ◽  
Kenneth Gable ◽  
Sita D. Gupta ◽  
Lan-Ying Shi ◽  
...  
Keyword(s):  
Chain Length ◽  
Small Subunit ◽  
Fatty Acyl ◽  
Substrate Affinity ◽  
Serine Palmitoyltransferase ◽  
Membrane Structures ◽  
Long Chain Base ◽  
Chain Lengths ◽  
Long Chain

Sphingolipids typically have an 18-carbon (C18) sphingoid long chain base (LCB) backbone. Although sphingolipids with LCBs of other chain lengths have been identified, the functional significance of these low-abundance sphingolipids is unknown. The LCB chain length is determined by serine palmitoyltransferase (SPT) isoenzymes, which are trimeric proteins composed of two large subunits (SPTLC1 and SPTLC2 or SPTLC3) and a small subunit (SPTssa or SPTssb). Here we report the identification of an Sptssb mutation, Stellar (Stl), which increased the SPT affinity toward the C18 fatty acyl-CoA substrate by twofold and significantly elevated 20-carbon (C20) LCB production in the mutant mouse brain and eye, resulting in surprising neurodegenerative effects including aberrant membrane structures, accumulation of ubiquitinated proteins on membranes, and axon degeneration. Our work demonstrates that SPT small subunits play a major role in controlling SPT activity and substrate affinity, and in specifying sphingolipid LCB chain length in vivo. Moreover, our studies also suggest that excessive C20 LCBs or C20 LCB-containing sphingolipids impair protein homeostasis and neural functions.

13C.N.M.R. chemical shift and crystal structures of cyclic paraffins of long chain lengths

1987 ◽  
Vol 61 (9) ◽  
pp. 563-565 ◽  
Author(s):  
M. Takenaka ◽  
T. Yamanobe ◽  
T. Komoto ◽  
I. Ando ◽  
H. Sato
Keyword(s):  
Chemical Shift ◽  
Crystal Structures ◽  
Chain Lengths ◽  
Long Chain

scholarly journals Single-Nucleotide Polymorphisms Found in themigAandwbpXGlycosyltransferase Genes Account for the Intrinsic Lipopolysaccharide Defects Exhibited by Pseudomonas aeruginosa PA14

2015 ◽  
Vol 197 (17) ◽  
pp. 2780-2791 ◽  
Author(s):  
Youai Hao ◽  
Kathleen Murphy ◽  
Reggie Y. Lo ◽  
Cezar M. Khursigara ◽  
Joseph S. Lam
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Specific Antigen ◽  
Nucleotide Polymorphisms ◽  
Core Oligosaccharide ◽  
Polysaccharide Antigen ◽  
Single Nucleotide ◽  
Content Type ◽  
Chain Lengths ◽  
Long Chain

ABSTRACTPseudomonas aeruginosaPA14 is widely used by researchers in many laboratories because of its enhanced virulence over strain PAO1 in a wide range of hosts. Although lipopolysaccharide (LPS) is an important virulence factor of allP. aeruginosastrains, the LPS of PA14 has not been characterized fully. A recent study showed that the structure of its O-specific antigen (OSA) belongs to serotype O19. We found that the OSA gene cluster of PA14 shares ∼99% identity with those of the O10/O19 group. These two serotypes share the same O-unit structure, except for anO-acetyl substitution in one of the sugars in O10. Here we showed that both PA14 and O19 LPS cross-reacted with the O10-specific monoclonal antibody MF76-2 in Western blots. Analysis by SDS-PAGE and silver staining showed that PA14 LPS exhibited modal chain lengths that were different from those of O19 LPS, in that only “very long” and “short” chain lengths were observed, while “medium” and “long” chain lengths were not detected. Two other novel observations included the lack of the uncapped core oligosaccharide epitope and of common polysaccharide antigen (CPA) LPS. The lack of the uncapped core oligosaccharide was caused by point mutations in the glycosyltransferase genemigA, while the CPA-negative phenotype was correlated with a single amino acid substitution, G20R, in the glycosyltransferase WbpX. Additionally, we showed that restoring CPA biosynthesis in PA14 significantly stimulated mature biofilm formation after 72 h, while outer membrane vesicle production was not affected.IMPORTANCEP. aeruginosaPA14 is a clinical isolate that has become an important reference strain used by many researchers worldwide. LPS of PA14 has not been characterized fully, and hence, confusion about its phenotype exists in the literature. In the present study, we set out to characterize the O-specific antigen (OSA), the common polysaccharide antigen (CPA), and the core oligosaccharide produced by PA14. We present evidence that PA14 produces an LPS consisting of “very-long-chain” and some “short-chain” OSA belonging to the O19 serotype but is devoid of CPA and the uncapped core oligosaccharide epitope. These intrinsic defects in PA14 LPS were due to single-nucleotide polymorphisms (SNPs) in the genes that encode glycosyltransferases in the corresponding biosynthesis pathways. Since sugars in CPA and the uncapped core are receptors for different bacteriocins and pyocins, the lack of CPA and an intact core may contribute to the increased virulence of PA14. Restoring CPA production in PA14 was found to stimulate mature biofilm formation.

scholarly journals n-Alkane Profile of Argemone mexicana Leaves

2010 ◽  
Vol 65 (9-10) ◽  
pp. 533-536 ◽  
Author(s):  
Indranil Bhattacharjee ◽  
Anupam Ghosh ◽  
Nandita Chowdhury ◽  
Soroj Kumar Chatterjee ◽  
Goutam Chandra ◽  
...  
Keyword(s):  
Carbon Number ◽  
Epicuticular Waxes ◽  
Carbon Preference Index ◽  
Argemone Mexicana ◽  
Mature Leaves ◽  
Preference Index ◽  
Chain Lengths ◽  
First Time ◽  
Long Chain ◽  
Carbon Number Predominance

An n-hexane extract of fresh, mature leaves of Argemone mexicana (Papaveraceae), containing thin-layer epicuticular waxes, has been analysed for the first time by TLC, IR and GLC using standard hydrocarbons. Seventeen long-chain alkanes (n-C18 to n-C34) were identified and quantified. Nonacosane (n-C29) was established as the n-alkane with the highest amount, whilst octadecane (n-C18) was the least abundant component of the extracted wax fraction. The carbon preference index (CPI) calculated for the hydrocarbon sample with the chain lengths between C18 and C34 was 1.2469, showing an odd to even carbon number predominance.

scholarly journals Unique molecular species of phosphatidylcholine containing very-long-chain (C24-C38) polyenoic fatty acids in rat brain

1990 ◽  
Vol 265 (3) ◽  
pp. 763-767 ◽  
Author(s):  
B S Robinson ◽  
D W Johnson ◽  
A Poulos
Keyword(s):  
Fatty Acids ◽  
Rat Brain ◽  
Molecular Species ◽  
Carbon Chain ◽  
Neonatal Rat ◽  
Adult Rat ◽  
Adult Rat Brain ◽  
Chain Lengths ◽  
Neonatal Rat Brain ◽  
Long Chain

Rat brain has been shown to contain polyenoic very-long-chain fatty acids (VLCFA) belonging to the n-3 and n-6 series with four, five and six double bonds and even-carbon chain lengths from 24 to 38. These fatty acids are almost exclusively located in unusual molecular species of phosphatidylcholine at the sn-1 position of the glycerol backbone, whereas saturated, monoenoic and polyenoic fatty acids with less than 24 carbon atoms are present at the sn-2 position. Polyenoic VLCFA phosphatidylcholine in neonatal rat brain is enriched with n-6 pentaenoic and n-3 hexaenoic VLCFA with up to 36 carbon atoms, whereas the corresponding phospholipid in adult rat brain mainly contains n-6 tetraenoic and n-3 pentaenoic VLCFA with up to 38 carbon atoms. The total amount of polyenoic VLCFA associated with phosphatidylcholine is highest in the brain of immature animals. Polyenoic VLCFA phosphatidylcholine appears to be predominantly confined to nervous tissue in rats, and it is envisaged that this phospholipid is of physiological significance.

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