Question

practice exam 2 2020 cell biology

1) Professor Kornberg discovered the first DNA polymerase and won the Nobel Prize for doing so. The specific biochemical assay he used to identify this enzyme was: a) Protein purification by column chromatography b) E. coli mutants c) The principle of limited sloppiness d) Ability to replicate DNA e) Calf thymus DNA

Answer 1

Ans. Protein purification by column chromatography

Sol. DNA polymerase I (also known as kornberg enzyme) is the first DNA polymerase discovered in E. coli. It was discovered by Arthur Kornberg, who subsequently won the Nobel prize for his work. The work was helped by the recent instalment of fermentor in the deperment for the growth of E. coli  which supplied hundreds of grama of logs phase E. coli. With the aid of column chromatography Kornberg's team was able to obtain a severe thousand fold purified but not yet homogeneous preparation of DNA polymerase. While still impure, the enzyme proved the capable of DNA polymerase. This DNA synthesis was aided by the addition of DNA as a primer.