Foundation of Lipids

• Mycobacterium tuberculosis evades both the human and immune system and antibiotic drugs due in part to a thick cell wall containing lipids known as mycolic acids
• The inflammatory response of bee sting is triggered by either Melittin or Phospholipase A
• Melittin is a 26 residue peptide that interacts with the membrane and creates a leak
• Phospholipase A is a hydrolytic enzyme that damages the membrane which actually causes inflammatory activity
• Lipids are energy storage, hydrophobic, mixed bags of organic molecules, and are components of biological membranes
• Lipids are water insoluble
• Lipids store more energy than carbohydrates because they have more C-H bonds
• Lipids can be extracted from the cell by organic solvents like acetone, and chloroform
• The lipid bilayer is the basic structural support of the biological membrane that is made out of two layers of lipids
• Lipids also function as enzyme cofactors, electron carriers, light absorbing pigments, hydrophobic anchors, emulsifying agents, hormones, and intracellular messengers
• Lipids are considered unique from the different biomolecules because they are all heterogenous
• Lipids can be either simple or complex
• Simple lipids contain C, H, and O
• Complex lipids contains C, H, O, N, P, and S
• Storage lipids are store energy in a compact form and are stored in technical organelles
• Membrane lipids contribute to the structural integrity and the fluidity of cell membranes
• Triacylglycerol is an example of a storage lipids which consists of fatty acids esters of glycerol
• The glycerol backbone contains a small organic molecule with three hydroxyl groups
• Membrane lipids have the capacity to form lipid bilayers
• Each lipid in membrane must assume the form to have a polar head and two nonpolar tails
• The examples of membrane lipids include Phospholipids and Glycolipids
• Phospholipids are lipids that contains phosphate groups
• Glycerophospholipids is a category under phospholipids that are fatty acid diglycerides with a phosphatidyl ester attached to the terminal carbon
• Glycerophospholipids contains a phosphate and alcohol which are the polar heads while the fatty acid carbon chains are the nonpolar tails
• A nonpolar tail which is bent represents an unsaturated bonds in cis configuration
• Sphingosine is a an 18-carbon amino alcohol with an unsaturated hydrocarbon chain
• Sphingolipids is made up of a sphingosine backbone, where the glycerol component is replaced by a long-chain amino alcohol at C2, which is amide linked to a fatty acid and a phosphate group
• This structure is a sphingolipid

  
• Glycolipids are lipids containing carbohydrates
• Sphingolipids in glycolipids has the same structure in sphingolipids in phospholipids, but the phosphate group is replaced with a carbohydrate
• This structure is a sphingolipid

  
• This structure is glycerophospholipids

  
• Triacylglycerols and Glycerophospholipids contain fatty acids and glycerol which are esterified
• Fats, oils, and waxes include triacylglycerols
• Fats and waxes are solid at room temperature while oils are liquid at room temperature
• Waxes are harder than fats because of the ester reaction between the saturated fatty acid chain and an alcohol
• Fatty acids are carbon chains with one methyl group on one end and a carboxyl group on the other end
• The number of carbons in a fatty acid determines its melting point
• As the length of the chain increases, the melting point also increases
• The increase or decrease in melting point indicates the amount of hydrophobic interaction between the hydrocarbon chain of the fatty acids