Thi question has two compared parts: Joshua Lederberg worked with strains of col

Question

Thi question has two compared parts:

Joshua Lederberg worked with strains of coli strains that unable to make all the nutrients they need. He observed that when he mixed two different strains together, some of their daughter offspring could survive without any nutrient supplements. What is the significance of these observations?

Jan-Hendrick Hehemann observed the presence of a porphyranase gene in the gut microbes of an unweaned infant. What was the significance of this discovery? (Was the porpyranase gene found in human cells or bacterial cells int he unweaned infant?)

Explanation / Answer

Joshua was working with coli strains. He observed that theses coli strains were uncapable of making the nutrients they need. But when he mixed two strains he found that the daughter strains could survive without nutrients, This means that the ecoli strains could share genetic information through recombination. The genes of the two strains got mixed and created a new strain with better features.

Jan obseved the presence of porphyranase gene in the gut microbes. Usually it is observed in people who eat oceanic sea-weed or nori. These genes have been transferred by the oceanic bacteria and help in the digestion of sea-weed. But here we have an unweaned infant which means he has'nt eaten nori. But it is a known fact that essential flora and bacteria will be transferred from the mother to child through birth canal. Likewise these acquired genes must be transferred to infant from mother. The porphyranase genes will be found in the gut bacterial cells.

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