Question

The bacterial enzyme streptokinase is used to digest fibrin in patients with atherosclerosis. Why doesn't the injection of streptokinase cause a streptococcal infection?

2- How do we know that streptokinase will break down fibrin and not functional tissue?

3- bromouracil is used as an anti cancer drug it is mistaken for thymine by cellular enzymes during DNA replication, name the enzyme site the nucleoside analog is probably binding.

4- Is glucose completely broken down in respiration or fermentation?

5- How does aerobic and anaerobic respiration differ?

Answer 1

1) streptokinase required for dissolving blood clot as it break down fibrin protein. It does not cause infection as for infection complete organismr is which causes disease and spread in form of droplet like mycobacterium. If we take protein, it is not harmful.

2) we already done several experiments using human skin cell line and treating it with streptokinase which does not dissolve or act on cells or tissue .it only act on fibrin protein. And we know enzyme are very specific so it won't bond with any other tissue except fibrin.

3) it will bind to DNA polymerase thymidine site and incorporate 5 bromouracil instread of thymidine.

4)glucose is completely breakdown in aerobic respiration as it will completely oxidized in form of CO2 and H2O with release of huge amount of energy 32 ATP while in case of fermentation ,glucose is partially oxidized to form lactic or ethanol with net release of 2 ATP .

5) aerobic respiration is characteristic of higher organism where food is completely oxidized in presence of oxygen into CO2 and H2O with relases of huge amount of energy. Here final electron acceptor is oxygen to form water.

While anaerobic respiration, oxygen is absent and food is partially oxidized and small amount of energy release. It's characterstics of ancient and lower organisms. Here final electron acceptor is like S, Fe, Cu, NO3, NO2.

Hope it's clear..thanks