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where fAT and fGC are fractions of AT and GC base pairs, respectively.
Melting temperature
The melting temperature is calculated as follows. For sequences of length 15 or longer:
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Tm = 64.9 + 41 * (nG + nC - 16.4) / (nA + nT + nG + nC)
For shorter sequences:
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Tm = (nA + nT) * 2 + (nG + nC) * 4
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Click on the gear icon near Melting temperature label and the Melting temperature settings dialog will be opened.
Note, that UGENE computes Tm fot sequence regions from 8 to 10000 bp. Otherwise, an undefined value N/A is output.
See the corresponding page for settings details.
nmole/OD260
The amount of DNA or RNA represented in nanomoles per 1 unit of absorbance at 260 nm dissolved in 1 ml cuvette with 1 cm pathlength.
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