Bleomycin_Spence
Bleomycin is a protein in the chemotherapy drug Blenoxane which inhibits the division of cancer cells, and “works by killing rapidly growing cells. This drug will affect all fast growing cells, cancer cells and normal cells, in [the] body” (Carlson 1). The drug aims to halt the growth of a malignant tumor, by attaching to the cancerous cell’s DNA and breaking the strand, which prohibits the division of cells for reproduction. To a lesser extent, the protein also has the ability to break RNA strands and proteins created by the cancerous cell. Specifically, Bleomycin is a glycopepetide antibiotic with specific tumor inhibiting functions and the ability to bond to cytosine-guanine rich portions of cancerous DNA. Using iron ions with two valence electrons, copper, and inactive and active ligands (Metal bonded to an molecule or ion through coordinate bonding), the oxygen bonded to the divalent ion can produce a free radical, which has the ability to break DNA at the 3'-4' bonds in the deoxyribose sides of the double helix structure. This prevents the nitrogenous bases in the cancerous DNA from bonding, resulting in the inability of that cell to further replicate. The metal ions and oxygen are essential to the reaction’s ability to break apart the cancerous DNA strand. In addition, a CO in the primary structure of the protein is also essential to the function of Bleomycin because without this molecule, the protein would be unable to bond to the DNA strand.
