Open AccessCharge heterogeneity of heat‐labile enterotoxins from human enterotoxigenic Escherichia coli
Author(s) -
Tsuji Takao,
Yao Shunkun,
Encarnacion Joya Josephine,
Honda Takeshi,
Miwatani Toshio
Publication year - 1989
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1989.tb03541.x
Subject(s) - isoelectric focusing , heat stable enterotoxin , isoelectric point , enterotoxigenic escherichia coli , escherichia coli , enterotoxin , polyacrylamide gel electrophoresis , molecular mass , gel electrophoresis , electrophoresis , protein subunit , chemistry , biology , biochemistry , microbiology and biotechnology , enzyme , gene
We purified heat‐labile enterotoxins (LThs) from YT3, H‐10407 and YT240 strains isolated from human diarrheal patients. These LThs were immunologically identical to each other. The molecular weights of their A and B subunits were also the same by means of SDS‐polyacrylamide gel electrophoresis. However, the ionic charges of the molecular surfaces of these LThs were different as shown by polyacrylamide gel isoelectric focusing. Though the p I points of B subunits of the LThs were identical to each other, the p I points of A subunits were found to be different. These data suggest that the ionic charge differences among A subunits cause differences in holo LThs in their charge, and that there is heterogeneity among A subunits produced by strains of human enterotoxigenic Escherichia coli .