Reference no: EM132416777

Problem: Radioactive isotopes of various elements can be used to label molecules for use in studies of metabolic pathways. For example, 14C is a radioactive isotope of carbon and naturally occurs at much lower rates than non-radioactive 12C (i.e. most molecules contain 12C carbon atoms). A cell can be fed a nutrient molecule labeled with the radioactive isotope and scientists can detect where the radioactive isotope ends up.

Required:

a) In a laboratory experiment, a culture of E. coli is fed 14C -labeled glucose and grown under aerobic conditions. What pathways would the radioactive isotope travel through? What is the final end product that the radioactive carbon would end up in?

b) In a second experiment E. coli is fed 14C-labeled acetyl CoA and grown under conditions that promote biosynthetic pathways. What molecules would be radioactively labeled at the end of the experiment?