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

G. L. Madsen, Floyd C. Knoop

Research output: Contribution to journalArticle

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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.

Original languageEnglish (US)
Pages (from-to)1051-1053
Number of pages3
JournalInfection and Immunity
Issue number3
Publication statusPublished - Jan 1 1980


All Science Journal Classification (ASJC) codes

  • Immunology

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