Distribution of the dienic long chain bases in shellfish sphingophosphonolipids

Glyco- and sphingophosphonolipids from the medusa Phyllorhiza punctata: NMR and ESI-MS/MS fingerprints

The medusa Phyllorhiza punctata has been found in Brazilian waters where it is an exotic species, having arrived in ballasts from the Indo-Pacific Ocean in the general region of North Australia and Indonesia. Fatty acids of the intact animal and its component umbrella, oral arms, and mucus were identified. Two different groups of glycolipids and a sphingolipid were isolated by silica-gel column chromatography and characterized using GC-MS, ESI-MS, 1D, 2D (13)C, (1)H and (31)P NMR spectroscopy. They were sulfoquinovosyldiacylglycerol (SQDG), monogalactosyldiacylglycerol (MGDG), and ceramide aminoethylphosphonate (CAEP). The CAEP long chain base (LCB) and its polar head group (PHG) formed by partial hydrolysis, were analyzed by ESI-MS/MS. The probable origin of MGDG and SQDG in the jellyfish is the result of an endosymbiotic association with a microalga of the Dinoflagellate group, since these lipids are commonly found in photosynthetic membranes.

Sphingophosphonolipid molecular species from edible mollusks and a jellyfish

The goal of this study is to supplement the composition and nature of sphingophosphonolipids diversity from edible mollusks (Mytilus galloprovincialis, Eobania vermiculata) and from jellyfish Pelagia noctiluca, organisms rich in phosphonolipids. M. galloprovincialis contained a major ceramide 2-aminoethylphosphonate (CAEP-IM) and a minor ceramide that was detected chromatographically as the methyl analog (CAEP-IIM). In CAEP-IM, saturated fatty acids (FA) of 14, 16 and 18 carbons amounted to 68.8%; also 52.5% dihydroxy bases were detected. On thin layer chromatography, the Rf for CAEP-IIM was smaller than the Rf for CAEP-IM because of an increase of 22.0% in 2OH-16:0 FA, plus 29.2% trihydroxy bases (phytosphingosine). Similarly, a ceramide 2-methylaminoethylphosphonate (CAEP-IIE, 1.5% of phospholipids) was quantitated in Eobania (apart from the previously reported major CAEP, 7.6%). In CAEP-IIE, saturated and hydroxy FA of 14, 16 and 18 carbons amounted to 37.0 and 37.8%; 29.1% dihydroxy and 23.0% trihydroxy bases were detected in the same molecule. Eobania's unsaturated FA percentages (total lipids: 66.3, polar: 47.5, neutral: 59.0) were similar to those previously found for other land snails. A suite of two minor CAEP (CAEP-IIP, CAEP-IIIP) was quantitated in Pelagia at 2.0 and 1.3% of phospholipids (apart from the previously reported major CAEP, 21.0%) identified chromatographically as methyl analogs. In CAEP-IIP, saturated FA of 14, 16, 18 and 19 carbons amounted to 56.0%; 12.6% dihydroxy and 34.1% trihydroxy bases were also detected in CAEP-IIP. The Rf CAEP-IIIP<Rf CAEP-IIP owing to an increase of +8.5% of hydroxy FA and +12.3% of trihydroxy bases. The compositions of CAEP-IIM and CAEP-IIE appear to be specific of each organism, while the composition of molluscan or jellyfish major sphingophosphonolipids appears not specific.

Sphingophosphonolipids, phospholipids, and fatty acids from Aegean jellyfish Aurelia aurita

The goal of this study is to elucidate and identify several sphingophosphonolipids from Aurelia aurita, an abundant but harmless Aegean jellyfish, in which they have not previously been described. Total lipids of A. aurita were 0.031-0.036% of fresh tissue, and the lipid phosphorus content was 1.3-1.7% of total lipids. Phosphonolipids were 21.7% of phospholipids and consisted of a major ceramide aminoethylphosphonate (CAEP-I; 18.3%), as well as three minor CAEP (II, III, IV) methyl analogs at 1.3, 1.1, and 1.0%, respectively. The remaining phospholipid composition was: phosphatidylcholine, 44.5%, including 36.2% glycerylethers; phosphatidylethanolamine, 18.6%, including 4.5% glycerylethers; cardiolipin, 5.6%; phosphatidylinositol, 2.6%; and lysophosphatidylcholine, 5.0%. In CAEP-I, saturated fatty acids of 14-18 carbon chain length were 70.8% and were combined with 57.3% dihydroxy bases and 23.4% trihydroxy bases. The suite of the three minor CAEP methyl analogs were of the same lipid class based on the head group, but they separated into three different components because of their polarity as follows: CAEP-II and CAEP-III differentiation from the major CAEP-I was mainly due to the increased fatty acid unsaturation and not to a different long-chain base, but the CAEP-IV differentiation from CAEP-I, apart from fatty acid unsaturation, was due to the increased content of hydroxyl groups originated from both hydroxy fatty acids and trihydroxy long-chain bases. Saturated fatty acids were predominant in total (76.7%), polar (83.0%), and neutral lipids (67.6%) of A. aurita. The major phospholipid components of A. aurita were comparable to those previously found in a related organism (Pelagia noctiluca), which can injure humans.

Comparative investigation of phospholipids and fatty acids of freshwater molluscs from the Volga river basin

1. Four Gastropoda species and two Bivalvia species from the Volga river basin were examined. 2. Distribution of phospholipids in the molluscs was studied by qualitative and quantitative micro thin-layer chromatography. 3. Major phospholipid classes, phosphatidylethanolamine and phosphatidylcholine, were found to contain plasmalogens. 4. One mollusc species notably contained 67 fatty acids including 25 saturated (both iso and anteiso), 24 monoenoic, five dienoic, four trienoic and eight polyenoic compounds identified by capillary gas chromatography; fatty acid contents in the other studied species were considerably lower. 5. Relatively high concentrations of nonmethylene-interrupted fatty acids were detected in certain examined species.

Occurrence of ceramide digalactoside as the main glycosphingolipid in the marine sponge Halichondria japonica

The main glycosphingolipid of the sponge Halichondria japonica was isolated and its structure was determined to be ceramide digalactoside, Gal alpha 1----4Gal beta 1----1Cer, using FAB/MS, IR, 1H-NMR and chemical methods such as permethylation analysis and degradation techniques. The ceramide moiety was composed mainly of 4-hydroxy-iso-octadecasphinganine and 2-hydroxy-docosanoic acid. Interestingly, the branched long-chain bases were comprised of 70% total long-chain bases and 17.5% 4-hydroxy-anteiso-nonadecasphinganine. Ceramide monohexoside, consisting of galactosyl ceramide (81%) and glucosyl ceramide (19%), was also isolated as a minor component. The composition of the ceramide moiety was nearly the same as that of ceramide digalactoside.

Fragmentation pathways of O-trimethylsilyl ethers of dihydroxy long-chain bases analysed by linked-scan mass spectrometry

The fragmentation pathways of O-trimethylsilyl (TMS) ethers of long-chain bases were studied by the linked-scan technique and exact mass measurements of the characteristic ion of O-trimethylsilyl long-chain bases detected by gas chromatography combined with electron-impact mass spectrometry. The results indicate that there are three pathways: the M+ - 15 (CH3) - 90 (TMSOH) - 74 [OSi(CH3)2] series, the M+ - 103 (CH2OTMS) - 90 (TMSOH) series and the M+ - 132 (CHNH2CH2OTMS) series.

Determination of the presence of ceramide aminoethylphosphonate and ceramide N-methylaminoethylphosphonate in marine animals by fast atom bombardment mass spectrometry

Phosphonosphingolipids from 15 kinds of shellfish were analyzed by fast atom bombardment mass spectrometry to determine the contents of ceramide aminoethylphosphonate (CAEPn) and ceramide N-methylaminoethylphosphonate (CMAEPn). Two pairs of ions, at m/z 126 and 140 in the positive ion mode and at m/z 124 and 138 in the negative ion mode, were used to distinguish between aminoethylphosphonic acid and N-methylaminoethylphosphonic acid in CAEPn and CMAEPn. Interestingly, mollusca in the early stage of evolution have both CAEPn and CMAEPn, while most in the middle stage have only CMAEPn and those in the highest stage have only CAEPn.

Cerebroside of the dimorphic human pathogen, Candida albicans

Structural studies on the cerebroside isolated from the yeast form of a dimorphic pathogen, Candida albicans were carried out using fast atom bombardment mass spectrometry (FAB/MS), proton magnetic resonance spectrometry, gas chromatography-mass spectrometry and usual chemical methods. The component sugar was only glucose attached to ceramide in a beta-configuration. The major fatty acid was 2-hydroxystearic acid (62%). The predominant long chain base was identified as 9-methyl-C18-sphinga-4,8-dienine which is widely distributed in fungi and reported to be essential to the fruit-inducing activity of fungi. Therefore, the structure of the main molecular species of the cerebroside was determined to be N-2-hydroxystearoyl-1-O-beta-glucosyl-9-methyl-C18-sphinga-4 ,8-dienine. Cerebroside prepared from the mycelial form of C. albicans has the same structure.

Characterization of aminoalkylphosphonyl cerebrosides in muscle tissue of Turbo cornutus

From muscle tissues of the marine snail (Turbo cornutus) aminoalkylphosphonyl cerebrosides, which had been shown to be present in visceral parts were isolated. Their structure was determined by degradative methods and by characterization of components by gas chromatography-mass spectrometry. The aminoalkylphosphonyl cerebroside fraction consisted of a major portion of 1-O-[6'-O-(N-methylaminoethylphosphonyl) galactosyl] ceramide and a minor portion of a novel lipid, 1-O-[6'-O-(aminoethylphosphonyl)galactosyl] ceramide. The fatty acids of the fraction were mainly palmitic (53.3%) and 2-hydroxy palmitic acid (14.6%). The long chain bases were mainly dihydroxy C22: 2(36.6%), C18:1 (14.6%) and trihydroxy bases were also found as minor components.

Phosphonoglycoprotein from Metridium senile--heterogeneity of glycoproteins containing aminoethylphosphonic acid

1. After separation by SDS gel-chromatography, analysis of AEP-containing glycoproteins from M. senile, indicated 66% amino acids with 220 AEP res./1000 res. and 30% carbohydrate for high mol. wt (greater than 10(7) forms and 80% amino acids with 25-50 AEP res./1000 res. and 10% carbohydrate for low mol. wt (2-4 x 10(4) forms. 2. Uronic acids, sulfate, lipid, and sialic acids were absent. 3. Mild base digestion released AEP-hexosamine containing oligosaccharides and destroyed ser-thr residues in the high mol. wt components. 4. Phosphonoglycoproteins appear to be acidic connective tissue components with AEP linked to hexosamine containing oligosaccharide side chains.