Question

The antibiotic streptomycin inhibits protein synthesis in bacteria. If this antibiotic is added to a culture of animal cells, protein synthesis in the cytoplasm continues normally. However, over time, the population of mitochondria in the cell decreases. More specifically, the protein-synthesis machinery inside the mitochondria is inhibited. Explain this observation based on what you know about the origins of the modern eukaryote. (With respect to the number of mitochondria within the cell) what would you expect to observe if, in a new experiment, the animal cells were treated with diphtheria toxin, a protein that is known to block eukaryotic protein synthesis (but does not have any impact on bacterial growth)?

Answer 1

According to endomsymbiotic theory eukaryotes are evolved by having a bacteria within it which is known as mitochondria nowdays .

So this may be reason that mitochondrial protein synthesis inhibited by streptomycin ..

In case of diphtheria toxin fragment A of diphtheria toxin inhibits protein synthesis in mitochondria and mitoplasts by inhibiting mitochondrial energy transduction. And fragment a is responsible for uncoupling of mitochondria ...mechanism is not well known yet ...