Abstract
Two variants of Escherichia coli heat-stable enterotoxin Ip, in which the amino acid residue at position 11 was substituted with lysine or arginine, were purified to near homogeneity from the culture supernatants of toxin-producing mutant strains. Neither the purified heat-stable enterotoxin Ip(Lys-11) nor the purified heat-stable enterotoxin Ip(Arg-11) showed a positive response in the suckling mouse assay or in the mouse intestinal loop assay. Furthermore, live bacteria producing these mutant heat-stable Ip enterotoxins did not cause fluid accumulation in mouse intestinal loops, in contrast to bacteria producing native heat-stable enterotoxin Ip. Nevertheless, antisera raised against both heat-stable enterotoxin Ip(Lys-11) and heat-stable enterotoxin Ip(Arg-11) neutralized the enterotoxic activity of native heat-stable enterotoxin Ip. These results demonstrate that heat-stable enterotoxin Ip(Lys-11) and heat-stable enterotoxin Ip(Arg-11) lose enterotoxicity but retain epitopes which are common to native heat-stable enterotoxin Ip.
Original language | English |
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Pages (from-to) | 191-195 |
Number of pages | 5 |
Journal | FEMS Microbiology Letters |
Volume | 98 |
Issue number | 1-3 |
DOIs | |
Publication status | Published - Nov 1 1992 |
Externally published | Yes |
Keywords
- Diarrhea
- Escherichia coli
- Heat-stable enterotoxin
- Mutation
- Vaccine
ASJC Scopus subject areas
- Microbiology
- Molecular Biology
- Genetics