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Homework Help: DNA melt curve questions

  1. Oct 6, 2012 #1
    1. The problem statement, all variables and given/known data

    You have a dye, Sybr GreenI which binds only to double stranded DNA (not single stranded). Once bound, it fluoresces strongly and can be used to monitor DNA melting (transition from double stranded to single stranded).

    (i) on the axes provided draw the DNA melt curve for a sample of E. coli DNA which has been mixed with Sybr GreenI.
    --> the axes shown has Temperature for x-axis and Fluorescence for y-axis.
    on the same graph show the melt curve for a sample of DNA
    (ii) with a lower %(G+C) content
    (iii) from the same source dissolved in a buffer at pH>9 prior to the measurements.

    2. Relevant equations

    3. The attempt at a solution

    (i) okay so im thinking the shape of the curve is like an S
    kind of like this: http://www.entelechon.com/wp-content/uploads/2008/10/dna_melting-300x178.gif [Broken]
    but is it exactly like that? or is the other way?

    (ii) for this one i know that i just have to draw the exact same shape except more towards 0 since more GC content means higher melting point.

    (iii) im not sure about this one.
    help please?
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Oct 7, 2012 #2
    bump. anyone?
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