Lipids have a hydrophobic nature because of the predominantly of hydrocarbon chains in their structure. They are insoluble or poorly soluble in water, but readily soluble in non polar solvents such as ether and benzene.
Characteristics of Lipids:
Amphiphatic
Naturally occurring
Soluble in organic solvents but insoluble in water
Undergo saponification
Undergo emulsification
Classification and biological functions of Lipids:
• Fatty Acids:
Energy sources
Biosynthetic precursors
• Triglycerols:
Storage
Transport
• Phosphoglycerides:
Membranes components
• Ketone bodies:
Energy sources
• Sphingolipids:
Membrane components
• Eicosanoids:
Modulators of physiological activity
• Cholesterol:
Membrane component …show more content…
Structure:
Sphingomyelin , which is derived from the amino alcohol(sphingosine) is the only sphingolipid that contains phosphate and has no sugar moiety. It is formed from ceramide, which is the core structure of naturally occuring sphingolipids, including the glycosphingolipids.
Degradation of sphingomyelin:
Sphingomyelinase degrade sphingomyelin. It is a lysosomal enzyme that hydrolytically removes phosphorycholine, leave a ceramide. On the other hand ceramide cleaved by ceramidase into sphingosine and a fatty acid. Due to the degradation of sphingomyelin ceramide and sphingosine released which play role as intracellular messengers. Ceramide involved in response to stress. Many nerve cells which are rich in sphingomyelin contain membranous sheath that surrounds and electrically insulates them.
Degradation of sphingomyelin
2- Cerebrosides:
These are simplest sphingolipids are actually ceramides with head groups that contain a single sugar residue. Moreover these are ceramide monohexosides, the most important being galactocerebrosides and glucocerebroside. Present in neural tissue membranes, particularly the myelin