D-aminolevulinic acid dehydratase is essential for the biosynthesis of hemoglobin. Inhibition of this enzyme interferes with the formation of blood to the point of anemia. The active site zinc ion binds to four ligands, three of which a sulfur atom. When lead replaces zinc, it only binds to the three sulfur atoms. The reason for this is the emerging free electron pair of the lead cation. It acts like an electronic shield on the one hand, pushing away the fourth ligand. Such a dramatic geometrical distortion at the active center could explain why lead inhibits this enzyme.
Parisel took a closer look at two proteins that bind to lead you. Calmodulin, a calcium-binding protein, plays an important role in regulating and transporting the calcium cation in the human body. A calcium ion binds to seven ligands at the active centers of the enzyme. When one of the four possible calcium ion is replaced by calmodulin by lead, lead ion remains approximately heptacoordinated but the active site is distorted and inefficient remaining three remaining three sides a reduced performance.. Lead does the most damage to the nervous system, brain and blood. This type of damage is particularly severe for children as they may be irreversible. Complexing agents , which are used to grip the metal cations as an antidote. However, these substances are not lead-specific, which means of hemoglobin.A complete Index , seeAbout the Book: Careers Opportunities in the biotechnology and Drug Development, After 1933 Harbor Laboratory) written by Toby Freedman . It is 409 pages in length and has to hardcover .