|
Nucleotide Molecular Weights
|
Nucleotide
|
MW (g/mol)
|
|
Ribonucleotide Triphosphates
(Avg. MW = 499.5)
|
|
ATP
|
507.2
|
|
CTP
|
483.2
|
|
GTP
|
523.2
|
|
UTP
|
484.2
|
|
Ribonucleotide Monophosphates
(Avg. MW = 339.5)
|
|
AMP
|
347.2
|
|
CMP
|
323.2
|
|
GMP
|
363.2
|
|
UMP
|
324.2
|
|
Deoxyribonucleotide
triphosphates (Avg. MW = 487.0)
|
|
dATP
|
491.2
|
|
dCTP
|
467.2
|
|
dGTP
|
507.2
|
|
dTTP
|
482.2
|
|
Deoxyribonucleotide
Monophosphates (Avg. MW = 327.0)
|
|
dAMP
|
331.2
|
|
dCMP
|
307.2
|
|
dGMP
|
347.2
|
|
dTMP
|
322.2
|
Nucleic Acid Molecular Weight Conversions
Exact M.W. of ssRNA (e.g.,
RNA Transcript)
M.W. = (An x 329.2) + (Un x
306.2) + (Cn x 305.2) + (Gn x 345.2) + 159ª
An, Un, Cn,
and Gn are the number of each respective nucleotide
within the polynucleotide.
M.W. calculated is valid
at physiological pH.
ªAddition
of "159" to the M.W. takes
into account the M.W. of a 5' triphosphate.
Exact M.W. of ssDNA (e.g.,
Oligonucleotides)
M.W. = (An x 313.2) + (Tn x
304.2) + (Cn x 289.2) + (Gn x 329.2) + 79.0ª
An, Tn, Cn,
and Gn are the number of each respective nucleotide within
the polynucleotide.
ªAddition
of "79.0" to the M.W. takes
into account the 5' monophosphate left by most restriction enzymes.
No phosphate is present at the 5' end of strands made by primer extension.
Approximate M.W.'s of
Nucleic Acids
M.W. of ssRNA
= (# nucleotides x 320.5) + 159.0
M.W. of ssDNA = (# nucleotides x 303.7) + 79.0
M.W. of dsDNA = (# nucleotides x 607.4) + 157.9
ssRNA Size and Mass Conversions
|
Size (nt)
|
Daltons or g/mol
|
1 µg equivalent
|
|
pmol
|
molecules
|
|
20
|
6,569
|
152.23
|
9.17 x 1013
|
|
100
|
32,209
|
31.05
|
1.87 x 1013
|
|
300
|
96,309
|
10.38
|
6.25 x 1012
|
|
500
|
160,409
|
6.23
|
3.75 x 1012
|
|
1000
|
320,659
|
3.12
|
1.88 x 1012
|
|
1800
|
577,059
|
1.73
|
1.04 x 1012
|
ssDNA Size and Mass Conversions
|
Size
(nt)
|
Daltons
or g/mol
|
1 µg
equivalent
|
|
pmol
|
molecules
|
|
20
|
6,153
|
162.52
|
9.79 x 1013
|
|
100
|
30,449
|
32.84
|
1.98 x 1013
|
|
300
|
91,189
|
10.97
|
6.6 x 1012
|
|
500
|
151,929
|
6.58
|
3.96 x 1012
|
|
1000
|
303,779
|
3.29
|
1.98 x 1012
|
|
1800
|
546,739
|
1.83
|
1.1 x 1012
|
dsDNA Size and Mass Conversions
|
Size
(nt)
|
Daltons
or g/mol
|
1 µg
equivalent
|
|
pmol
|
molecules
|
|
20
|
12,306
|
81.26
|
4.89 x 1013
|
|
100
|
60,898
|
16.42
|
9.89 x 1012
|
|
300
|
182,378
|
5.48
|
3.3 x 1012
|
|
500
|
303,858
|
3.29
|
1.98 x 1012
|
|
1000
|
607,558
|
1.65
|
9.91 x 1011
|
|
1800
|
1,093,478
|
0.91
|
5.51 x 1011
|
Absorbance Units to Nucleic
Acid Concentration Conversion
1 A260 dsDNA = 50 µg/ml
1 A260 ssDNA = 37 µg/ml
1 A260 ssRNA = 40 µg/ml
Nucleotide Absorbance
Maxima and Molar Extinction Coefficients
|
Nucleotide
|
Absorbance Maximum at pH 7.0 (nm)
|
Molar Extinction Coefficient at pH 7.0
|
|
ATP
|
259
|
15,400
|
|
CTP
|
271
|
9,000
|
|
GTP
|
253
|
13,700
|
|
UTP
|
262
|
10,000
|
|
dATP
|
259
|
15,200
|
|
dCTP
|
271
|
9,300
|
|
dGTP
|
253
|
13,700
|
|
dTTP
|
267
|
9,600
|
|