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Results for Standard Proteins with WM ranging from 6.5 kDa to 476 kDa

Molecular Weights Determined from ASTRA analysis.

ProteinOligomeric statePredicted
MW (kDa)a
# runsAverage MW (kDa)Standard deviation
(kDa)b
Average (%) errorc
Alcohol dehydrogenasetetramer147.44144.00.92.4
BSA (monomer)monomer66.4567.11.01.2
BSA (dimer)dimer132.95137.13.93.2
Carbonic anhydrasemonomer29.0429.20.20.8
Cytochrome Cmonomer12.3512.00.62.4
Apo-ferritin24 x monomer475.92470.42.61.2
α-lactalbuminmonomer14.2214.30.010.9
Aldolase (rabbit)tetramer156.81155.1 1.1
β-lactoglobulinmonomer18.3220.10.39.7
Enolase (rabbit)ddimer93.7486.4d1.97.8 d
Enolase (yeast)ddimer93.3179.5 d 14.9d
Myoglobinemonomer17.0314.20.916.3e
Transferrinmonomer75.2276.91.02.3
Tripsin inhibitormonomer20.0120.5 2.3
Ovalbuminmonomer42.81042.50.71.4
Aprotininfmonomer6.526.80.54.6
Median:0.92.3

(column: Superdex 200 [Pharmacia], buffer: 20 mM HEPES, 100 mM KCl, 1 mM EDTA pH=8.0). Further information with regard to colored protein designations can be viewed here.

a predicted MW was calculated based on protein sequence as retrieved from the
ExPASy molecular biology WWW server of the Swiss Institute of Bioinformatics
(SIB) http://expasy.hcuge.ch/ (except of Aprotinin)
b SD represents one standard deviation calculated as
S.D. = SQRT{ [sum(Yi-M)^2]/(n-1)}, where
M is arithmetic mean calculated as M = sum(Yi )/n
(given in column "Average Experimental MW")
Yi is a result of the "ith" measurement , i.e. MW determined in the "ith" run
n is a number of runs
c % error is calculated as an average from the absolute values of
{100x[(Experimental MW-pred. MW)/pred. MW]}
d these dimers are unstable under chromatographic condition used, i.e. buffer with
1 mM EDTA.
e colored protein: absorbs at the wavelength of the laser beam (633 nm). Thus
the amount of scattered light is smaller and leads to underestimated Mw as the
instrument is not capable of correcting for the absorbed light.
f analyzed on Superdex 75 column in 20 mM HEPES, 600 mM KCl, 1 mM EDTA ,
1 mM DTT, pH=8.0