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. 1980 Jun;28(3):1051–1053. doi: 10.1128/iai.28.3.1051-1053.1980

Physiochemical properties of a heat-stable enterotoxin produced by Escherichia coli of human origin.

G L Madsen, F C Knoop
PMCID: PMC551059  PMID: 6995319

Abstract

Concentrated cell-free filtrates, prepared from a human strain of enterotoxigenic Escherichia coli, were subjected to isoelectric focusing, molecular sieve chromatography, and polyacrylamide disc gel electrophoresis. Isoelectric focusing in a pH 3 to 5 gradient resulted in two biologically active peaks, I and II, that electrofocused at pI 1.5 and 3.8, respectively. Molecular sieve chromatography of the major enterotoxic peak (II) at pH 3.8 indicated a molecular weight of 2,500. Polyacrylamide disc gel electrophoresis of ST revealed a single protein band containing enterotoxic activity.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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