Research in lipids attracted special attention recently. While originating in Life Sciences, current topics of interest are making important connections with nutrition and health issues, and with technological applications of lipids and their derivatives in New Materials Science, for example. A discipline of Lipidomics studies chemical and metabolic lipid transformations in living organisms and offers a comprehensive platform for combining relevant data on lipid changes for further research. Recent studies of fatty acid-related compounds, such as triglycerides, phospholipids, and cholesteryl esters, are adding many significant roles and functions to the canonical properties formerly assigned to them. Lipidomics applied to microorganisms is of special significance as a powerful research tool and also due to its many biotechnology prospects.
The microbial lipids' functions are numerous: first of all, bacteria use cell wall lipids to prevent alien things from getting in the cell and for keeping its inner contents within. In this reflection fluorescence microscopy picture (Fig.1) of Bacillus subtilis cell, the area of the cell wall lipids shows such delineation and outlined in blue. Membrane lipid homeostasis is based on diversity of biochemical and genetic regulatory mechanisms and represents a vitally significant fact of bacterial cell physiology . Based on several common building blocks, lipids form an abundance of secondary and tertiary molecular structures, often in cooperation with variety of complex proteins. Thus hierarchical scaffolds form where numerous cascades of metabolic transformations occur.
Hence, in terms of developing new therapeutics that may block pathogen bacterial phospholipid synthesis, or control disorders of lipid metabolism, for example, the studies and application of relevant lipids will be of great interest. Some of the recent substances of interest are:
This novel area of microbial lipids use is based on their natural ability to compartmentalize and delineate environments, producing nano size vesicles for therapeutic or pharmaceutical purposes. The lipid building blocks in the case normally may have no pronounced pharmacological effects themselves but they serve, in their natural form or derivative one, as vehicles for pharmaceuticals, e.g. in transdermal systems (Fig.3). These include advanced drug delivery systems based on scaffolding dendrimers or liposome structures of specifically tailored microbial lipids. A suitable example would be gadolinium carrying Gd-DTPA-PE hybrid constructs based on phosphatidylethanolamine moieties. They are succesfully applied in Magnetic Resonance Imaging and cancer therapy. Many new hybrid materials for Engineering, such as gold nano shells and quantum dots, were created recently through biomimetic synthetic routes employing nano reactors that mimic bacterial cell walls . A creation of such 3-dimensional structures is often monitored by various NMR spectroscopy tools.
The Metabolomics database at the BMRB contains 1H, 13C, 13CDEPT90, DEPT135, TOCSY, COSY45, HSQC, HMBC and HSQC-TOCSY-ADIA NMR spectral data for compounds related to these lipids researches (such as cardiolipin, bmse001105), presented as the time domain data, the spectra pictures as well as the tables of peak transitions and assigned chemical shifts. The compounds include various fatty acids and their esters, sphingolipids, cholesterol and related substances, isoprenoids, lipid synthesis cofactors etc. Besides direct research, the data are of a real interest for building of the modular suites of exercises for laboratory sessions in Physical Chemistry and Instrumental Analysis, and specifically useful for teaching the 1D and 2D 1H-13C data assignments, providing visual context .
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The picture of bacteria cell (Fig.1) comes from http://www.mpg.de/4334236/Bacterial_roundabouts; © Roland Wedlich-Söldner / Copyright: MPI for Biochemistry