JAMES KING-HOLMES / SCIENCE PHOTO LIBRARY JAMES KING-HOLMES / SCIENCE PHOTO LIBRARY
DNA repair enzyme. Computer simulation of a HAP1 (lower frame, called APE/Ref-1) enzyme repairing a damaged Deoxyribonucleic Acid (DNA, stick model) molecule. HAP1's surface has been colour-coded: red areas are positively charged & blue areas are negative. HAP1's positively-charged active site is at upper centre. DNA carries a cell's genetic code. The DNA in each cell is damaged 2000-10,000 times a day by hydrolysis reactions which convert N-glycosyl bonds to apurinic/apyrimidinic breaks. DNA damage can cause cell death or cancer. HAP1 is the first protein to recognise the damage & starts repairs by breaking DNA's molecular backbone so other proteins can replace the faulty section.
Model release not required. Property release not required.