Identification of lipids in the cuticle of the parasitic nematode Anisakis simplex and the somatic tissues of the Atlantic cod Gadus morhua.

The main aim of this work was to assign the cuticular lipids identified in a parasitic nematode and to distinguish those originating from its host. The hypothesis that long-chained fatty acids and sterols are imported by the parasite in the absence of certain enzymes was also tested. The organisms (Anisakis simplex and Gadus morhua) were extracted in petroleum ether and dichloromethane. Matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF) was used to identify unknown components, and electrospray ionization mass spectrometry (ESI/MS) to verify recognized groups of lipids. The lipid classes identified in the surface layer were free saturated and unsaturated fatty acids, triacylglycerols, sterols and non-polar sphingolipids (ceramides, sphingoid bases). The most abundant fraction consisted of fatty acids. The predominant saturated acids were tetradecanoic acid in the petroleum ether extract of A. simplex, hexadecanoic acid in the dichloromethane extract of A. simplex, and also the polyunsaturated octadecahexaenoic and octadecatrienoic acids in both extracts of the parasitic nematode. The mass spectrum revealed the presence of fatty acids with different numbers of carbons, and with odd and even numbers of unsaturated bonds. The MALDI-TOF mass spectrum also identified triacylglycerols (TAGs). The dominant short-chain TAGs were CoCoCy:(1), CoCoPg and Bu0:0B:(6). The majority of TAGs were found in the ether and dichloromethane extracts of A. simplex. Sterols were the least common class of lipids found in the nematode extracts; most likely, this is the fraction that is entirely incorporated from the host organism because of the parasite's inability to synthesize them. MALDI-TOF also identified non-polar sphingolipids--ceramides and sphingoid bases. The signals due to N-octanoyl-D-erythro-octasphinganine (m/z 288.3) and N-tetranoyl-D-erythro-tetradecasphinganine (m/z 316.4) were dominant on the mass spectra; quite a large number of short-chain non-polar sphingolipids were also identified.

Smith degradation of the O-antigenic polysaccharide of Salmonella Dakar: structural studies of the products.

Two different oligosaccharides were obtained from the Smith degradation of the O-polysaccharide isolated from the lipopolysaccharide of Salmonella Dakar. The structures of these oligosaccharides were investigated by chemical analysis, NMR spectroscopy and MALDI-TOF mass spectrometry. The following structures of these products were determined: alpha-D-GalpNAc-(1-->4)-alpha-D-Quip3NAc-(1-->3)-alpha-L-Rhap-(1-->2)-threitol and [Formula: see text] where Quip3NAc is 3-acetamido-3,6-dideoxyglucose. The reaction products confirmed the structure of the repeating unit of the Salmonella Dakar O-polysaccharide reported previously [Kumirska, J.; Szafranek, J.; Czerwicka, M.; Paszkiewicz, M.; Dziadziuszko, H.; Kunikowska, D.; Stepnowski, P. Carbohydr. Res. 2007,342, 2138-2143].

The structure of the O-polysaccharide isolated from the lipopolysaccharide of Salmonella Dakar (serogroup O:28).

The structure of the O-antigenic part of the lipopolysaccharide (LPS) of Salmonella Dakar was analysed using chemical methods, NMR spectroscopy and mass spectrometry. The following structure for the repeating unit of the O-polysaccharide was determined: [see text] where Quip3NAc is 3-acetamido-3,6-dideoxyglucose. This is the first published structure of the O-polysaccharides from 101 serotypes of Salmonella bacteria belonging to serogroup O:28 (formerly M) in the Kauffmann-White scheme.

Identification of the cuticular lipid composition of the Western Flower Thrips Frankliniella occidentalis.

The Western Flower Thrips Frankliniella occidentalis effectively resists many insecticides, but it can be controlled by the use of bioinsecticides such as entomopathogenic fungi. The epicuticular chemistry of these insects is therefore of great interest, and accordingly, the cuticular lipid composition of F. occidentalis was analysed. It was found that the cuticular lipids of both the adult and larval stages of F. occidentalis consist of two groups of compounds--hydrocarbons and free fatty acids. The same hydrocarbon pattern was found in both adults and larvae, with the exception of n-hentriacontane, which was detected only in adult insects. The following homologous series were identified: n-alkanes from C-25 to C-29 (31) with the marked dominance of odd numbers of carbon atoms, 3-methylalkanes with 26 and 28 carbon atoms, and branched monomethylalkanes (branched at C-9, -11, -13 and -15) with 26, 28 and 30 carbon atoms. The chemical composition of the free fatty acids consists of two homologous series: saturated (C(14:0), C(16:0), C(18:0)) and unsaturated fatty acids (C(16:1) and C(18:1)). This analysis confirmed the lack of potential inhibitors of entomopathogenic fungi in the cuticular lipids of this insect species.

Accumulation of nodularin in sediments, mussels, and fish from the Gulf of Gdansk, southern Baltic Sea.

In the Gulf of Gdansk, as in other parts of the Baltic Sea, toxic blooms of Nodularia spumigena are an annual phenomenon. In the present work, the accumulation of nodularin (NOD), a cyanobacterial pentapeptide hepatotoxin, in sediments, blue mussels, and flounders from the Gulf of Gdansk was studied by enzyme-linked immunosorbent assay (ELISA). In the surface layers of the sediments NOD concentration ranged from 2.3 ng/g dry weight (dw) several months after cyanobacterial bloom to 75 ng/g dw during the bloom. The highest toxin content in mussels was 139 ng/g dw. In two sampling stations situated in the coastal waters of the Gulf of Gdansk the concentrations of NOD in sediments and mussels were significantly lower than those measured in the Gulf of Finland. In sediments and mussels collected in the Gulf of Gdansk, the toxin was also detected in March when N. spumigena did not occur. In flounder, NOD accumulated in the liver (489 ng/g dw), guts (21 ng/g dw), and gonads (21 ng/g dw). Hybride quadrupole-time-of-flight liquid chromatography/mass spectrometry/mass spectrometry (TOF-LC/MS/MS) confirmed the presence of NOD in sediment, mussel, and fish samples. Additionally, other NOD analogues, ([DMAdda(3)]NOD and [dhb(5)]NOD), were detected in sediments and mussel tissue. No NOD conjugates with reduced glutathione or cysteine were found in fish and mussels.

Structure and heterogeneity of the O-antigen chain of Salmonella Agona lipopolysaccharide.

Lipopolysaccharide of Salmonella Agona smooth-type cells was obtained from bacteria by a hot phenol-water extraction procedure. Mild acid hydrolysis of lipopolysaccharide, followed by gel filtration, yielded the pure O-polysaccharide. Abequose, rhamnose, mannose, galactose and glucose in the molar ratio 0.8 : 1.0 : 1.0 : 1.1 : 0.5 were detected, and their linkages were established. Sugar configurations were determined by gas chromatography. Two repeating units, namely -->2)-[alpha-Abep-(1-->3)-]-alpha-d-Manp-(1-->4)-alpha-l-Rhap-(1-->3)-alpha-d-Galp-(1-->and -->2)-[alpha-Abep-(1-->3)-]-alpha-d-Manp-(1-->4)-alpha-l-Rhap-(1-->3)-[alpha-d-Glcp-(1-->4)-]-alpha-d-Galp-(1-->, were deduced from nuclear magnetic resonance studies. The effort to separate them was unsuccessful. An immunochemical test performed by means of Western blotting with anti O12 serum demonstrated that glucose was present in the longer lipopolysaccharide chains, at some distance from the core region.

Leaf surface sesquiterpene alcohols of the potato (Solanum tuberosum) and their influence on colorado beetle (Leptinotarsa decemlineata Say) feeding.

The structures of two previously unknown sesquiterpene alcohols of the potato (Solanum tuberosum) were assigned. The potato alcohols were obtained by steam-distillation, preparative column chromatography, and separation into fractions by HPLC on a silica gel column. The fractions were studied by GC-FID, GC-MS, and NMR spectroscopy. The potato sesquiterpene alcohols were identified as kunzeaol (6-alpha-hydroxygermacra-1(10),4-diene) and ledol. These two compounds were used in feeding tests with larvae and beetles of the Colorado potato beetle (Leptinotarsa decemlineata Say). In a bioassay, kunzeaol was found to act as a feeding attractant for the beetles.

Characterization of nodularin variants in Nodularia spumigena from the Baltic Sea using liquid chromatography/mass spectrometry/mass spectrometry.

Nodularin is a potent hepatotoxic cyclic pentapeptide produced by planktonic cyanobacterium Nodularia spumigena. Bloom and culture samples of the cyanobacterium collected and isolated from the Gulf of Gdansk, southern Baltic Sea, were analyzed. Hybrid quadrupole-time-of-flight liquid chromatography/mass spectrometry/mass spectrometry (TOF-LC/MS/MS) with ionspray (ISP) and collision-induced dissociation (CID) were used to characterize nodularin and its analogues. The identification process was based on the comparison of recorded product ion spectra with the previously reported FAB-MS/CID (high-energy) mass spectra of the corresponding nodularin variants. Amino acid structures and sequences were derived from the fragmentation pattern of the [M+H](+) ions. Apart from unmodified nodularin with an arginine residue (NOD-R), three demethylated variants have been found. The sites of demethylation were located on aspartic acid [Asp(1)]NOD, the Adda residue [DMAdda(3)]NOD, and dehydrobutyric acid [dhb(5)]NOD. In two other nodularin variants an additional methyl group is located in the Adda [MeAdda]NOD and Glu [Glu(4)(OMe)]NOD residues. The linear NOD and the geometrical isomer of NOD-R, reported earlier in N. spumigena from New Zealand, have also been detected. Two of the total eight nodularin variants characterized in the present study, [dhb(5)]NOD and [MeAdda]NOD, have not been described earlier.

Analysis of leaf surface sesquiterpenes in potato varieties.

A comparative study of potato leaf sesquiterpenes was carried out. GC, GC-MS, and NMR analyses were used to identify and quantify the sesquiterpenes in the leaf surfaces of 10 potato (Solanum tuberosum) varieties. Two sesquiterpene alcohols and 17 sesquiterpene hydrocarbons were identified and quantitatively determined. The distribution of the sesquiterpenes was found to be variety-specific. The sesquiterpene contents of the different potato varieties were subjected to cluster and principal component analyses. The eight potato varieties of the main chemotype cluster were dominated by beta-caryophyllene (9-148 ng/cm2), germacrene D (2-46 ng/cm2), germacrene D-4-ol (0.4-31 ng/cm2), beta-sesquiphellandrene (1-34 ng/cm2), and an unknown sesquiterpene alcohol III (0.2-37 ng/cm2). Chemometric classification distinguished two varieties, Mila and Vistula, from a major cluster. The Vistula variety was distinguished from the others by its high contents of beta-caryophyllene, alpha-humulene, germacrene D, and germacrene D-4-ol and the Mila variety by beta-elemene, trans-alpha-bergamotene, (Z)-beta-farnesene, (E)-beta-farnesene, trans-beta-bergamotene, beta-sesquiphellandrene, and unknown sesquiterpene alcohols I, II, III.