BIOC 2580 Lecture Notes - Lecture 16: The Double Helix, Erwin Chargaff, Fritz Albert Lipmann

• School: University of Guelph
• Department: Biochemistry
• Course: BIOC 2580
• Professor: John Dawson

Document Summary

Francis crick and james watson: relying on these accumulated data on dna structure, watson and crick were able to come up with a model for dna secondary structure in 1953. Chemical basis for the large free-energy change associate with atp hydrolysis: 1. Hydrolysis released the electrostatic repulsion among the negative charges: 2. The product inorganic phosphate has greater resonance stabilization than does atp: 3. Adp2- product rapidly ionizes to release a proton into a medium of very low [h+] driving the hydrolysis toward completion. Hydrolysis of atp: there are to high energy bonds (phosphoanhydride linkages) in atp, 1. Hydrolysis of the link between gamma and beta phosphate (nucleophilic attack of the y phosphate: yields adp and pi releasing ~30kj of energy, 2. Chemical mechanism that allows atp hydrolysis to drive reactions forward: example: glutamine synthetase, the cell drives the synthesis of glutamine forward by coupling the reaction to atp hydrolysis as illustrated by the atp -> adp + pi notation.