Q7. The protein MACKINS, which is composed of the newly discovered amino acids, binds to DNA. Multiple experiments were conducted to determine the nature of the binding and understand how binding varies by pH. The melting temperature of the DNA melting was measured at pH 6 and 8 and the fluorescence of MACKINS was measured at pH 6 and 8. The results are shown below. PH Melting temp Fluorescence (F) of DNA of MACKINS pH 6 control 6 DNA only 55C Control (normal) F pH 6 experiment DNA+ MACKINS 45C Increased F pH 8 control 8 DNA only 55C Control (normal) F pH 8 experiment DNA + MACKINS 55C Unchanged F a. Indicate 2 of the discovered amino acids that may be involved in binding to the outside of DNA structure. b. A poly-SARAH chain in the MACKINS sequence was shown to be present in the structure. How would you expect poly-SARAH to interact with the DNA at pH 6 and pH 8? c. How can you use this knowledge to explain the pH dependence on binding?
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The melting temperature of the DNA melting was measured at pH 6 and 8 and the fluorescence of MACKINS was measured at pH 6 and 8. Show more…
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