Martian organisms have DNA similar to Earth (Terran) DNA, but with a different s

Question

Martian organisms have DNA similar to Earth (Terran) DNA, but with a different set of bases, shown below. The bases are uniquely Martian.

b- Scientists attempt to interpret the Martian genetic code by first transforming it into a Terran counterpart using PCR. DNA polymeras is able to “read” Martian DNA, but the scientists find that only some of the Martian bases form stable pairs with the Terran ones. Please draw the potential base pairs and comment on their stability.

c- Attempts to culture Martian organisms on Earth fail; apparently, Martian DNA is stable at the colder temperatures on Mars but sometimes denatures at the warmer temperatures of Earth. Explain why Martian duplex DNA could be less stable than Terran duplex DNA.

d- If you attempted to isolate a Martian DNA gene using PCR, how would the typical “melt” and “anneal” temperatures be affected if there was a preponderance of base pair 1 (from a)? What about base pair 2 (from a)?

Explanation / Answer

Part A- The structure of Adenine resembles with the Ap of the given Martian organism. The thymine resembles with CAz because it has one oxygen atom and lesser number of nitrogen atoms than the Gf. The basic structure of pyrimidines contain oxygen atom. Therefore Ap and CAz are pyrimidines here. The Cm will bind to Gf.

Part b- The one reason behind the happened is the basic structure. Thymine contain one oxygen atom while cytosine contains two oxygen atoms. Therefore, thymine can work with terrain nucleotides but Cytosine will not.

Part c- This is the case of stability. If a nitrogen base does not contain the required numbers of atoms, then it will loose its stability. That things also are happening with Martian bases. The same thing will also happen with Duplex because still this is weaker than normal nitrogen base pairs.

Part D- Due to the strong temperature difference the melting and annealing both temperatures will drastically reduce from the Earth DNA duplication temperature.

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