BIOL355 Lecture Notes - Lecture 23: Lipid Peroxidation, Oxidative Stress, Catalase
Document Summary
While trying to stabilize, free radicals will attack and modify other molecules, altering their shape and function. Dna: nucleotide substitutions, single strand breaks and cross-links, evidence of free radical damage to dna in human breast cancer cells. Proteins: proteins can become oxidized (lose an electron, no longer functional, amino acids with thiol groups (sh) are easily oxidized, could alter the proteins conformation and function. Example: s shaped protein functional a free radical comes in and steals an electron and the proton. Another free radical comes in and steals an electron and the proton. Molecules leave with the 2 electrons and 2 h+ No longer free radicals since they have stabilized themselves stealing an electron from the protein. Basically they crosslink by oxidizing and forming age. Free radicals cause this: age, there is a 2-3 fold in oxidized proteins, proteins that are oxidized with age also usually become inactive. In the # of cross-links of protein (age/free radicals)