1-O-Alkylglyceryl Ether Lipids of the Gut Walls and Contents of an Abyssal Holothurian (Oneirophanta mutabilis)

Abstract

Um estudo de éter de glicerol foi realizado nos lipídios livres da membrana e do conteúdo do aparelho digestivo de uma espécie de holothuria abissal, Oneirophanta mutabilis. Foi detectada uma série desses compostos, saturados e insaturados, variando de C 15 a C 21 , totalizando de 5-12 % dos lipídios das amostras investigadas. Tanto as amostras das membranas quanto às dos conteúdos analisadas mostraram composições similares, sendo C 16:0 , C 16:1 , C 17:0 , C 18:0 e C 18:1 os componentes principais e, entre eles, C 18:0 o composto dominante para essa espécie de holoturia. O teor do carbono orgânico total (TOC) e de nitrogênio (N) também foram avaliados nas amostras de conteúdos do trato digestivo e decresceram do esôfago para o reto. A média da eficiência de assimilação média foi estimada em 40 e 55% para TOC e N respectivamente A study of the glyceryl ether composition of free lipids of gut walls and contents of an abyssal holothurian species, Oneirophanta mutabilis has been carried out. A series of saturated and unsaturated 1-O-alkylglyceryl ethers with alkyl side chains ranging from C 15 to C 21 were detected inthe gut walls and contents of O. mutabilis. Glyceryl ethers accounted for 5-12% of the total free lipids contents. Foregut, midgut and hindgut walls and contents have identical 1-O-alkylglyceryl ether compositions. The C 16:0 , C 16:1 , C 17:0 , C 18:0 and C 18:1 are the main glyceryl ethers with C 18:0 being dominant. The total organic carbon (TOC) and nitrogen (N) contents were also evaluated in gut contents of the digestive tract of O. mutabalis and these decreased from foregut to hindgut. The average assimilation efficiencies were estimated to be 40 and 55% for TOC and N respectively.

1-O-Alkylglycerol Ether Lipids in Two Holothurian Species:Cucumaria japonicaandC. okhotensis

“…In spite of similarity in biological functions of O-alkylglycerol ether lipids, the structure of their O-alkyl radicals may be different. The revealed differences between C. japonica and C. okhotensis were similar to those observed in the studies of some other holothurian species, for example S. japonicus, C. fraudatrix [5] and Oneirophanta mutabilis [12]. In these species, Fig.…”

Synthesis of neutral ether lipid monoalkyl-diacylglycerol by lipid acyltransferases

“…bonds on the glycerol backbone. Ether lipids are widely distributed in nature and have been found in bacteria (1), deep-sea holothurians (2), fish (3), and mammals, including humans (4).…”

Unusual Ether Lipids and Branched Chain Fatty Acids in Sea Cucumber (Cucumaria frondosa) Viscera and Their Seasonal Variation

“…Analysis of the components of glyceryl ethers derived from both DAGE and MAGE revealed unique alkyl chain structures that were characteristically rich in 16:0 and 18:0 ( Figure 2 ). Other studies have found a similar dominance of 16 and 18 carbon O -alkyl chains in DAGE and MAGE of C. japonica, C. okhotensis and Oneirophanta mutabilis [ 5 , 18 ]. This narrow range of alkyl structures indicates a high specificity for particular substrates in the pathways responsible for the biosynthesis of alkylglycerols [ 26 ].…”

“…The presence of ether lipids in C. frondosa viscera was expected as alkyl structures including saturated (branched and unbranched) and monounsaturated alkyl chains associated with an ether bond in glycerol ethers have been previously identified in Holothurians [ 5 , 6 , 18 ]. High levels of α-glyceryl ethers have been reported in lipid extracts of Stichopus japonicas (18%), C. fraudatrix (9.3%), and C. japonica and C. okhotensis (25–27%) [ 5 , 6 ].…”