Faculty of Chemistry, University of Gdańsk, ul. Sobieskiego 18/19, 80-952 Gdańsk, Poland.
Exp Parasitol. 2010 Mar;124(3):334-40. doi: 10.1016/j.exppara.2009.11.013. Epub 2009 Nov 27.
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.
本工作的主要目的是对寄生线虫中的表皮脂质进行归属，并区分源自其宿主的脂质。还测试了寄生虫在缺乏某些酶的情况下是否通过长链脂肪酸和甾醇进行输入的假设。使用基质辅助激光解吸飞行时间质谱（MALDI-TOF）来鉴定未知成分，使用电喷雾电离质谱（ESI/MS）来验证公认的脂质组。在表面层中鉴定的脂质类为游离饱和和不饱和脂肪酸、三酰基甘油、甾醇和非极性神经酰胺（神经酰胺、神经鞘氨醇碱）。最丰富的组分为脂肪酸。在 A. simplex 的石油醚提取物中，主要的饱和酸为十四烷酸，在 A. simplex 的二氯甲烷提取物中，主要的饱和酸为十六烷酸，在寄生线虫的两种提取物中，主要的多不饱和脂肪酸为十八碳六烯酸和十八碳三烯酸。质谱揭示了存在具有不同碳原子数和奇数和偶数不饱和键的脂肪酸。MALDI-TOF 质谱还鉴定了三酰基甘油（TAGs）。主要的短链 TAGs 为 CoCoCy：（1）、CoCoPg 和 Bu0：0B：（6）。大多数 TAGs存在于 A. simplex 的乙醚和二氯甲烷提取物中。甾醇是线虫提取物中发现的最常见的脂质类；很可能，由于寄生虫无法合成这些甾醇，因此这是完全从宿主生物体中掺入的部分。MALDI-TOF 还鉴定了非极性神经酰胺-神经酰胺和神经鞘氨醇碱。在质谱中，N-辛酰基-D-赤式-辛神经酰胺（m/z 288.3）和 N-四酰基-D-赤式-十四神经酰胺（m/z 316.4）的信号占主导地位；还鉴定了相当数量的短链非极性神经酰胺。
