Isotopic compositions of carbon-bound hydrogen in individual compounds from eight di€erent organisms were measured using isotope-ratio-monitoring gas chromatography±mass spectrometry. This technique is capable of measuring D/H ratios at natural abundance in individual lipids yielding as little as 20 nmol of H2, and is applicable to a wide range of compounds including hydrocarbons, sterols, and ...

Diatoms are unicellular algae that accumulate significant amounts of triacylglycerols as storage lipids when their growth is limited by nutrients. Using biochemical, physiological, bioinformatics, and reverse genetic approaches, we analyzed how the flux of carbon into lipids is influenced by nitrogen stress in a model diatom, Phaeodactylum tricornutum. Our results reveal that the accumulation o...

The growth, cellular total lipids, bioaccumulation amount, and bioaccumulation factors (BAFs) of 2,4,4'-tribromodiphenyl ether (BDE28), 2,2',4,4'-tetrabromodiphenyl ether (BDE47), and 2,2',4,4',5-pentabromodiphenyl ether (BDE99) in a semi-continuous culture of Prorocentrum donghaiense were studied in relation to nitrate (0, 128, and 512 micromol/L) and phosphate (0, 8, and 32 micromol/L) concen...

A proper regulation of membrane fluidity is critical for cellular activities such as communication between cells, mitosis, and endocytosis. Unsaturated lipids, a main component of biological membranes, are particularly susceptible to oxidative attack of reactive oxygen species. The oxidation of lipids can produce structural derangement of membranes and eventually alter the membrane fluidity. We...

Biological membranes contain an extraordinary diversity of lipids. Phospholipids function as major structural elements of cellular membranes, and analysis of changes in the highly heterogeneous mixtures of lipids found in eukaryotic cells is central to understanding the complex functions in which lipids participate. Phospholipase-catalyzed hydrolysis of phospholipids often follows cell surface ...

A number of enzymes in the cyclooxygenase and lipoxygenase pathways process fatty acids to generate a variety of bioactive lipids. Recent findings that link inflammation to carcinogenesis have started to reveal how these bioactive lipids function in cellular signaling pathways as lipid messengers that mediate responses to cellular injury through inflammatory processes (1). Downstream effects of...

Cells have thousands of different lipids. In the plasma membrane, and in membranes of the late secretory and endocytotic pathways, these lipids are not evenly distributed over the two leaflets of the lipid bilayer. The basis for this transmembrane lipid asymmetry lies in the fact that glycerolipids are primarily synthesized on the cytosolic and sphingolipids on the noncytosolic surface of cellu...

To investigate the mechanism of azalomycin F5a against methicillin-resistant Staphylococcus aureus (MRSA), the conductivity of MRSA suspension and the adenylate kinase activity of MRSA culture were determined with the intervention of azalomycin F5a, which were significantly increased compared to those of blank controls. This inferred that azalomycin F5a could lead to the leakage of cellular sub...

Domains are present in every natural membrane. They are characterized by a distinctive protein and/or lipid composition. Their size is highly variable from the nano- to the micrometer scale. The domains confer specific properties to the membrane leading to original structure and function. The determinants leading to domain organization are therefore important but remain obscure. This review pre...

Lipids are the building blocks of cellular membranes and are synthesized at distinct parts of the cell. A precise control of lipid synthesis and distribution is crucial for cell function and survival. The endoplasmic reticulum (ER) is the major lipid-synthesizing organelle. However, a subset of lipids is synthesized within mitochondria, and this aspect has become a focus of recent lipid researc...