Lipid molecular species

Schneiter, R. Brugger, B. Sandhoff, R. Zellnig, G. Leber, A. Lampl, M. Athenstaedt, K. Hrastnik, C. Eder, S. Daum, G. Paltauf, F. Wieland, F. T. Kohlwein, S. D. Electrospray ionization tandem mass spectrometry (ESI-MS/MS) analysis of the lipid molecular species composition of yeast subcellular membranes reveals acyl chain-based sorting/remodeling of distinct molecular species en route to the plasma membrane. J. Cell Biol. 1999,146,741-754. 

The pattern of thermotropic phase behavior exhibited by an aqueous dispersion of any lipid molecular species will vary considerably, depending on the length and structure of the hydrocarbon chains, the structure and charge of the polar headgroup, the nature of the link (ester or ether) of the hydrocarbon chains to the glycerol or sphingosine backbone, and other chemical features of the lipid under study. Also, the degree of hydration and the pH and ionic composition of the aqueous phase can affect lipid thermotropic phase behavior profoundly. However, even a cursory discussion of this topic is beyond the scope of this article, and the reader is referred to recent reviews for more detailed information (16-18). 

The selective hydrophobicity or amphiphilicity of some lipid molecular species play a most important biological role for the living cell, because it forces lipid molecules to accumulate, thus minimizing their contact to water. The non- polar lipid assemblies formatting in this way are the boundary of the living cell, separating it from its water environment. 

Lynch DV, Thompson GA. Retailored lipid molecular species a tactical mechanism for modulating membrane properties. Trans Biochem Sci 1984 9 442-445. 

Han, X., Abendschein, D.R., Kelley, J.G. and Gross, R.W., Diabetes-induced changes in specific lipid molecular species in rat myocardium, Biochem J 352 (2000) 79-89. 

Determination of Lipid Molecular Species Formed in Castor Microsomal Incubations with Radiolabeled Fatty Acids by HPLC Flow Counting Mann-Tsyh Lin, Jennifer M. Chen, Lucy P. Liao,... 

Fundamentally, lipidomics can be defined as the qualitative and quantitative determination of all lipid molecular species in a biological fluid, tissue, or cell type. This goal is impractical for individual groups of workers, but is a realistic aim, at least for the more abundant lipids, for consortia of lipid scientists. Such consorha exist and the Lipid Maps (http // www.lipidmaps.org/) grouping in the LFnited States has already published results from extensive joint studies of the human plasma lipidome... 

Ejsing, C. S., Duchoslav, E., Sampaio, J., Simons, K., Bonner, R., Thiele, C., Ekroos, K., and Shevchenko, A. 2006. Automated identification and quantification of glycerol phospho lipid molecular species by multiple precursor ion scanning. And. Chem. 78 6202-14. 

Culture Lipid Molecular species composition (% of total) ... 

Sukenik A, Yamaguchi Y and Livne A (1993) Alterations in lipid molecular species of the marine eustigmatophyte Nannochloropsis sp. J. Phycol. 29 620-626... 

Song, H., Hsu, P.P., Ladenson, J. and Turk, J. (2007) Algorithm for processing raw mass spectrometric data to identify and quantitate complex lipid molecular species in mixtures by data-dependent scanning and fragment ion database searching. J. Am. Soc. Mass Spectrom. 18, 1848-1858. 

Each individual molecular ion yields different characteristic product ions in a collision condition-dependent manner (see next section). These characteristic product ions are tightly associated with the building blocks of individual lipid molecular species and provide a pattern of individual lipid class from which individual molecular species can be relayed after considering the m/z value. Although it appears that the m/z values in a full scan mass spectrum within the mass range of interest serve as the variables in the product-ion analysis, the new dimension is the resultant product ions that constitute a 2D map from the building-block point of view. Therefore, in product-ion analysis, the yielded product ions could be conceivably recognized as a variable. 

MDMS-SL analyzes lipid molecular species in a combined targeted and nontargeted approach and extensively employs the building-block concept for identification of lipid molecular structures (see Chapter 2). The database for MDMS-SL should be as broad and flexible as possible and can be readily constructed based on the building blocks of individual lipid classes (see Chapter 1) [3]. Such a virtual database consists... 

Demonstrated the applications of the library for high-throughput lipid identification [7]. The group analyzed lipid extracts of the human plasma using a low-resolution mass spectrometer. Using LipidBlast, they structurally annotated a total of 264 lipids. The data set was cross-checked with manual peak annotations and data available from Lipid MAPS. Using accurate mass LC-MS/MS, they annotated a total of 523 lipid molecular species. A similar number of plasma lipids were obtained in comparison to those previously published [8, 9]. 

Samarakoon, T., Shiva, S., Lowe, K., Tamura, R, Roth, M.R. and Welti, R. (2012) Ara-bidopsis thaliana membrane lipid molecular species and their mass spectral analysis. Methods Mol. Biol. 918, 179-268. 

One of the yeasts, which were investigated the best, is the common bakers yeast, Saccharomyces cerevisiae, for which both complete genome and detailed protein data sets are available. S. cerevisiae contains a relatively simple, but conserved network of lipid metabolism/catabohsm pathways. This network controls the synthesis of hundreds of lipid molecular species [1], and therefore its full lipidome. As compared in Chapter 16, the biosynthesis and metabohsm of GPLs in the yeasts are very similar to those of higher eukaryotes, with three main exceptions. 

LIPID MOLECULAR SPECIES RETAILORING UNDER TEMPERATURE STRESS... 

Most plants respond to environmental stresses by changes in the lipid composition of their cel 1-membranes. Main transformations, observed in a long term period, are concerned with the phospholipid composition of membranes and the degree of unsaturation of component fatty acids (1). In the short term, some "retailoring" of lipid molecular species (intermolecular rearrangements of lipid acyl chains) can be observed (2). All these chemical changes would result in modifications of the physical state of membrane lipids. 

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