How blue light and enzymes repair damaged DNA

摘要

Photolyase is a DNA repair enzyme that utilizes blue light to repair UV light-induced damage that can cause skin cancer. Researchers have previously shown that photolyase works by splitting an anomalous linkage within the DNA helix that causes bunching and inhibits replication. Zheyun Liu et al. (pp. 14831-14836) attempted to determine the specific chemical and electron movements required to split this cyclobutane pyrimidine dimer by mutating small units of DNA and using UV absorption spectroscopy to probe—in increments as small as one-quadrillionth of a second—how an Escheri-chia coli photolyase changes and repairs the damage.