Concerning SDS-PAGE artifactual bands in the 60-70 kDa range, there is
evidence for two origins of these bands: 1) reduced keratin proteins or
2) reducing reagent (B-ME, DTT) contaminants.
1) keratin related bands - Ochs, D. (1983) Anal. Biochem. 135, 470-474
Berube, B. et al (1993) Anal. Biochem. 217, 331-333
2) DTT or B-ME contaminants-Tasheva, B. & Dessev, G. (1983) Anal. Biochem.
129, 98-102.
Beis, A. & Lazou, A. (1990) Anal. Biochem. 190,
57-59.
Suresh Kumar, T.K. et al (1993) Anal. Biochem.
213, 226-228.
Gorg, A. et al (1987) Electrophoresis 8, 122-124.
These artifacts can be mostly eliminated by alkylating your boiled reduced
sample (using iodoacetamide, methods in above refs). Keeping plates clean and
dust free is not enough if one wants to use high sensitivity silver staining
methods. For coomassie blue staining, cleanliness may suffise. I hope this is
helpful.
Neil W. Ross, Ph.D.
National Research Council Canada
Institute for Marine Biosciences
1411 Oxford St., Halifax, NS B3H 3Z1
(902)426-8402 FAX (902) 426-9413
Email: ROSSN at imb.lan.nrc.ca
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From: r.k.mcewen at bham.ac.uk (ANON)
Subject: SDS-PAGE problem
Date: Tue, 17 Jan 1995 18:50:01
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Recently I`ve been observing an artefactual band on my SDS-PAGE gels
regardless of whether there is any samples on it. This band typically runs
between 50 and 60 kDa right across the gel, through all the sample lanes and
varys in intensity from one to another.
To date, I have tried fresh reagents; a colleagues reagents and gel
equipment
all to no avail.
Needless to say, he does not see this band. I have tried to mimic his method
of preparing the gel but I am at a loss to explain it.
Any suggestion ?
