Function
β-defensins are cationic and can therefore interact with the membrane of invading microbes, which are negative due to lipopolysaccharides (LPS) and lipoteichoic acid (LTA) found in the cell membrane. The peptides have higher affinity to the binding site compared to Ca2+ and Mg2+ ions. The peptides will therefore exchange place with those ions, thus affecting the stability of the membrane. The peptides have a greater size compared with the ions which cause changes in the membrane structure. Due to changes in the electric potential, peptides will pass across the membrane and thus aggregate into dimers. Pore complex will be created as a result of breaking the hydrogen bonds between the amino acids in the terminal end of the strands connecting defensins monomers. Formation of pore complex will cause membrane depolarization and cell lysis.
Defensins not only have the ability to strengthen the innate immune system but can also enhance the adaptive immune system by chemotaxis of monocytes, T-lymphocytes, dendritic cells and mast cells to the infection site. Defensins will also improve the capacity of macrophage phagocytosis.
Read more about this topic: Beta Defensin
Famous quotes containing the word function:
“The function of comedy is to dispel ... unconsciousness by turning the searchlight of the keenest moral and intellectual analysis right on to it.”
—George Bernard Shaw (1856–1950)
“Morality and its victim, the mother—what a terrible picture! Is there indeed anything more terrible, more criminal, than our glorified sacred function of motherhood?”
—Emma Goldman (1869–1940)
“The mother’s and father’s attitudes toward the child correspond to the child’s own needs.... Mother has the function of making him secure in life, father has the function of teaching him, guiding him to cope with those problems with which the particular society the child has been born into confronts him.”
—Erich Fromm (1900–1980)