Plastoglubuli contain both structural proteins and enzymes involved in lipid synthesis and metabolism. The virus replicates on intracellular lipid membranes. These lipids vary in shape (see page on lipid polymorphism). Lower protein/lipid ratios make for less dense lipoproteins. Fatty acids are a family of molecules classified within the lipid macronutrient class. NKT cells bind to proteins that present lipid or glycolipid antigens. They are transported as complexes of lipid and proteins known as lipoproteins. Total concentration of molecules in categories such as protein, lipid or nucleic acid. The preparation method reveals the proteins embedded in the lipid bilayer. Uncouplers are capable of transporting protons through mitochondrial and lipid membranes. Activating PPARs induces the transcription of a number of genes that facilitate lipid metabolism. Glycolipids are lipid molecules bound to oligosaccharides, generally present in the lipid bilayer. Class IV bacteriocins are defined as complex bacteriocins containing lipid or carbohydrate moieties. It causes disruption of intermolecular interactions and dissociation of lipid bilayers. Knockout of the NF1 gene in muscle results in deregulated lipid metabolism and muscle weakness.