CHARACTERIZATION AND SEQUENCE OF A 33-KDA ENTEROHEMOLYSIN (EHLY1)-ASSOCIATED PROTEIN IN ESCHERICHIA-COLI

The nucleotide sequence of the 2.1-kb EcoRI-AccI fragment of the enter ohemolysin (Ehly)-associated plasmid, pEO21, has been determined. A th ird of this sequence encodes a 29.6-kDa protein, and coincides with th c location of Tn1725 insertions which inactivate the production of Ehl y. A protein of similar size (33-35 kDa) was found to be produced in l arge amounts by JM83[pEO21] and found to be immunologically related to the approximately 65-kDa protein made by the parental strain, C3888. DNA sequences coding for the 29.6-kDa protein of phiC3888, now designa ted Ehlyl, were found only in some enterohemolytic Escherichia coli in dicating the existence of multiple, genetically different Ehlys.