scholarly journals Glycoinositol phospholipids from Endotrypanum species express epitopes in common with saccharide side chains of the lipophosphoglycan from Leishmania major

1998 ◽  
Vol 329 (3) ◽  
pp. 665-673 ◽  
Author(s):  
Erika XAVIER DA SILVEIRA ◽  
Christopher JONES ◽  
Robin WAIT ◽  
O. José PREVIATO ◽  
Lucia MENDONÇA-PREVIATO

We have characterized glycoinositol phospholipids (GIPLs) from three strains of the trypanosomatid parasites Endotrypanum schaudinni and Endotrypanum monterogeii. Methanolysis of the intact GIPLs liberated methyl esters of tetracosanoic acid, docosanoic acid, octadecanoic acid and hexadecanoic acid and C20 and C21 phytosphingosines. Phosphoinositol oligosaccharides were released from the GIPLs by mild base treatment, and their structures were determined by compositional analysis, fast-atom-bombardment MS and NMR spectroscopy. Similar compounds were detected in all three strains, although their relative proportions varied. The predominant components in E. schaudinni strain LV59 and E. monterogeii LV88 were Galpβ1-3Galpβ1-3Manα1-3Manα1-4GlcNα1-6Ins-1-P and Arapβ1-2Galpβ1-3Galpβ1-3Manα1-3Manα1-4GlcNα1-6Ins-1-P, and the major phosphoinositol oligosaccharide in E. schaudinni LV58 was the hybrid-type GIPL Manα1-2(EtNP-6)Manα1-6(Galpβ1-3Manα1-3)Manα1-4GlcNα1-6Ins-1-P (where EtNP is ethanolamine phosphate). Several minor oligosaccharides containing additional galactose and/or arabinose residues were also detected.

1959 ◽  
Vol 26 (2) ◽  
pp. 190-195 ◽  
Author(s):  
R. P. Hansen ◽  
F. B. Shorland ◽  
N. June Cooke

Butterfat has been shown to contain the normal odd-numbered saturated acids n-nonadecanoic acid (C19), n-heneicosanoic acid (C21), and n-tricosanoic acids (C23).The presence of the normal even-numbered acids n-octadecanoic acid (C18), n-docosanoic acid (C22), n-tetracosanoic acid (C24) and n-hexacosanoic acid (C26) is conclusively established.n-Eicosanoic acid (C20) formerly assumed to be present in butterfat has been isolated and identified by its physical and chemical properties.


1994 ◽  
Vol 302 (3) ◽  
pp. 861-865 ◽  
Author(s):  
C A Redman ◽  
J E Thomas-Oates ◽  
S Ogata ◽  
Y Ikehara ◽  
M A Ferguson

The glycosylphosphatidylinositol membrane anchor of human placental alkaline phosphatase was isolated by exhaustive proteolysis followed by hydrophobic interaction chromatography. The resulting glycosylphosphatidylinositol-peptide was subjected to compositional analysis and chemical and enzymic modifications. The neutral-glycan fraction, prepared by dephosphorylation followed by HNO2 deamination and reduction, was sequenced using exoglycosidases and acetolysis. The phosphatidylinositol moiety was analysed by fast-atom bombardment mass spectrometry and gas chromatography-mass spectrometry. Taken together the data suggest the structure, Thr-Asp-ethanolamine-PO4-Man alpha 1-2Man alpha 1-6Man alpha 1-4GlcN-(sn-1-O- alkyl-2-O-acylglycerol-3-PO4-1-myo-D-inositol), which contains an additional ethanolamine phosphate group at an unknown position.


Author(s):  
Ann Kiplagat Jepkorir ◽  
Charles Maina Irungu ◽  
Philip Bett Kendagor

All parts of A. indica (neem) and R. communis (castor) plants have mostly been used as natural remedies in the control and treatment of several ailments, control of pests and insects, animal feeds and production of industrial products globally. The seed oils of A. indica and R. communis are known to have antidiabetic, anti-helminthic, antifertility, antioxidant, antibacterial, anti-inflammatory, anti-cancer, insecticidal and mosquitocidal activity. This study reports for the first time the chemical composition of A. indica and R. communis seed oils from Marigat, Baringo County, Kenya. Seed oils of A. indica and R. communis were   extracted from mature dried seeds through cold pressing and boiling respectively and chemical composition determined using Gas Chromatography (GC)-Mass Spectrometry (MS).  The constituents of both seed oils were dominated by saturated and unsaturated fatty acids, cyclic esters and methyl esters. The predominant constituents of R. communis were (Z)-6-Octadecenoic acid (37.33%), Ricinoleic acid (30.22%) and 13-Hexyloxacyclotridec-10-en-2-one (26.67%) while those of A. indica were 2-hexyl-1-decanol (30.97%), Octadecanoic acid (29.69%) and Oxalic acid, 6-ethyloct-3-yl ethyl ester (15.55%). Oils contained Hexadecanoic acid and Octadecanoic acid which are used in the manufacture of several products such as candles, soaps, lotions, perfumes and cosmetics. Octadecenoic acid is important in control of human diseases and Ricinoleic acid in production of alkyd resins for surface coating and biofuel.  From the results, A. indica and R. communis seed oils constituents have potential in the agricultural, industrial, comestics and pharmaceutical sectors but require further fractionation to isolate the bioactive compounds.


2000 ◽  
Vol 2 (20) ◽  
pp. 4515-4520 ◽  
Author(s):  
Marina Fix ◽  
Manfred Sieber ◽  
Michael Overs ◽  
Hans J. Schäfer ◽  
Hans-Joachim Galla

1995 ◽  
Vol 308 (1) ◽  
pp. 251-260 ◽  
Author(s):  
M Li ◽  
Z Lin ◽  
M E Johnson

Tryptophan and 5-bromotryptophan (5-BrTrp) are relatively potent inhibitors of sickle-haemoglobin polymerization. The binding sites of these compounds to normal and sickle haemoglobin (HBA and HBS) have been suggested, but not firmly established, through the use of spin-labelled derivatives and/or computer modeling. In the present study we approached the problem by utilizing the technique of photoaffinity labelling. The cyanomet forms of HBA and HBS were subjected to photoaffinity labelling with N alpha-(4-azidotetrafluorobenzoyl)tryptophan and N alpha-(1-ethyl-2-diazomalonyl)-5-bromotryptophan respectively. Both irradiated samples of HBA and HBS were denatured, digested with trypsin, and then separated by reversed-phase HPLC. A labelled tryptic peptide was isolated from the photolabelling of HBS with N alpha-(1-ethyl-2-diazomalonyl)-5-bromotryptophan. The peptide was identified to be Val1(alpha)-Lys7(alpha), with the label attached to Val1(alpha), by virtue of amino acid analysis and sequencing, in conjunction with fast-atom-bombardment MS. The binding mode of N alpha-(1-ethyl-2-diazomalonyl)-5-bromotryptophan is proposed and its relevance to the potency of the 5-BrTrp-based anti-sickling agents is discussed.


2002 ◽  
Vol 363 (3) ◽  
pp. 437-447 ◽  
Author(s):  
Laurent KREMER ◽  
Sudagar S. GURCHA ◽  
Pablo BIFANI ◽  
Paul G. HITCHEN ◽  
Alain BAULARD ◽  
...  

Phosphatidyl-myo-inositol mannosides (PIMs), lipomannan (LM) and lipoarabinomannan (LAM) are an important class of bacterial factors termed modulins that are found in tuberculosis and leprosy. Although their structures are well established, little is known with respect to the molecular aspects of the biosynthetic machinery involved in the synthesis of these glycolipids. On the basis of sequence similarity to other glycosyltransferases and our previous studies defining an α-mannosyltransferase from Mycobacterium tuberculosis, named PimB [Schaeffer, Khoo, Besra, Chatterjee, Brennan, Belisle and Inamine (1999) J. Biol. Chem. 274, 31625–31631], which catalysed the formation of triacyl (Ac3)-PIM2 (i.e. the dimannoside), we have identified a related gene from M. tuberculosis CDC1551, now designated pimC. The use of a cell-free assay containing GDP-[14C]mannose, amphomycin and membranes from Myobacterium smegmatis overexpressing PimC led to the synthesis of a new alkali-labile PIM product. Fast-atom-bombardment MS established the identity of the new enzymically synthesized product as Ac3PIM3 (i.e. the trimannoside). The results indicate that pimC encodes an α-mannosyltransferase involved in Ac3PIM3 biosynthesis. However, inactivation of pimC in Myobacterium bovis Bacille Calmette—Guérin (BCG) did not affect the production of higher PIMs, LM and LAM when compared with wild-type M. bovis BCG, suggesting the existence of redundant gene(s) or an alternate pathway that may compensate for this PimC deficiency. Further analyses, which compared the distribution of pimC in a panel of M. tuberculosis strains, revealed that pimC was present in only 22% of the clinical isolates examined.


1998 ◽  
Vol 334 (3) ◽  
pp. 585-594 ◽  
Author(s):  
Antonio M. GIL-SERRANO ◽  
Miguel A. ÍGUEZ-CARVAJAL RODR ◽  
Pilar TEJERO-MATEO ◽  
José L. ESPARTERO ◽  
Jane THOMAS-OATES ◽  
...  

The structure of a polysaccharide from Sinorhizobium frediiSVQ293, a thiamine auxotrophic mutant of S. fredii HH103, has been determined. This polysaccharide was isolated following the protocol for lipopolysaccharide extraction. On the basis of monosaccharide analysis, methylation analysis, fast atom bombardment MS, collision-induced dissociation tandem MS, one-dimensional 1H and 13C NMR and two-dimensional NMR experiments, the structure was shown to consist of the following trisaccharide repeating unit → 2)-α-d-Galp-(1 → 2)-β-d-Ribf-(1 → 9)-α-5-O-Me-Kdnp-(2 →, in which Kdn stands for deaminated neuraminic acid; 25% of the Kdn residues are not methylated. The structure of this polysaccharide is novel and this is the first report of the presence of Kdn in a rhizobial polysaccharide, as well as being the first structure described containing 5-O-Me-Kdn. This Kdn-containing polysaccharide is not present in the wild-type strain HH103, which produces a 3-deoxy-d-manno-2-octulosonic acid (Kdo)-rich polysaccharide. We conclude that it is likely that the appearance of this new Kdn-containing polysaccharide is a consequence of the mutation.


2003 ◽  
Vol 58 (7-8) ◽  
pp. 502-504 ◽  
Author(s):  
Ahmet C. Gören ◽  
Gökhan Bilsel ◽  
Mehmet Altun ◽  
Fatih Satıl

Abstract The chemical composition of fatty acid methyl esters (FAMEs) from seeds of S. thymbra and S. cuneifolia were analyzed by GC/MS. 7 FAMEs were identified from the seeds of S. thymbra mainly as 9-octadecenoic acid methyl ester (43.9%), hexadecanoic acid methyl ester (11.4%), 9,12,15-octadecatrienoic acid methyl ester (Z,Z,Z) (30.2%), and octadecanoic acid methyl ester (14.1%), while from the seed of S. cuneifolia 10 FAMEs were obtained with the main components, similar to S. thymbra. These were identified as 9-octadecenoic acid methyl ester (10.1%), hexadecanoic acid methyl ester (methyl palmitate, 34.6%), 9,12,15-octadecatrienoic acid methyl ester (Z,Z,Z) (6.3%) and octadecanoic acid methyl ester (1.8%).


1983 ◽  
Vol 213 (1) ◽  
pp. 261-265 ◽  
Author(s):  
R E Isaac ◽  
N P Milner ◽  
H H Rees

Ecdysonoic acid and 20-hydroxyecdysonoic acid have been purified from developing eggs of the desert locust, Schistocerca gregaria, by high performance liquid chromatography (h.p.l.c.), and their structures were determined by p.m.r. spectroscopy and fast atom bombardment mass spectrometry of the free and methyl ester derivatives. 20-Hydroxyecdysonoic acid was also characterized from Spodoptera littoralis pupae. The occurrence of both 20-hydroxyecdysonoic acid and ecdysonoic acid in Sp. littoralis pupae was also established by h.p.l.c. comparison of the 3H-labelled acids formed from [3H]ecdysone and of their methyl esters with the corresponding substances from Sch. gregaria. The significance of ecdysteroid acids as products of ecdysteroid inactivation is discussed.


1994 ◽  
Vol 77 (2) ◽  
pp. 525-532 ◽  
Author(s):  
Ronald D Plattner ◽  
Bruce E Branham

Abstract Fumonisin B1 (FB1) labeled on the branch methyl groups with deuterium was produced in liquid cultures, and methyl-D3-labeled methionine was added. The isolated FB1 had 90% incorporation of 6 deuterium atoms and 9% incorporation of 3 deuterium atoms. The labeled FB1 was used as an internal standard for 2 analytical methods to measure FB1 in extracts of corn, corn products, and cultures. One method was hydrolysis followed by gas chromatography/mass spectrometry (GC/MS) of the derivatized backbone, and the other was analysis by fast atom bombardment MS (FAB/MS). Incorporation of labeled FB1 into samples resulted in a GC/MS method with improved precision and accuracy and allowed for a quantitative FAB/MS method.


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