title: Comparison of effects of nicked and unnicked Escherichia coli heat-labile enterotoxin on Chinese hamster ovary cells.
abstract: The effect on nicking (proteolytic cleavage) of heat-labile enterotoxin (LT) on its activities on Chinese hamster ovary (CHO) cells was examined. LT nicked with trypsin induced morphological change (elongation) of CHO cells from round to spindle-shaped cells faster than did unnicked LT. The times for elongation of 50% of the CHO cells with nicked and unnicked LT were 3 and 6 h, respectively. The activity of nicked LT on CHO cells was not inhibited by antiserum 20 min after treatment, whereas that of unnicked LT was inhibited by antiserum until ca. 130 to 160 min after treatment. These data suggest that unnicked LT remains on the cell surface longer than nicked LT and thus induces morphological changes of CHO cells more slowly than does nicked LT.
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000378:metabolism / Q000494:pharmacology*; D002478:Cells, Cultured / Q000187:drug effects*; D006224:Cricetinae; D003412:Cricetulus; D004768:Enterotoxins / Q000378:metabolism / Q000494:pharmacology*; D004926:Escherichia coli; D029968:Escherichia coli Proteins; D005260:Female; D010053:Ovary; D013329:Structure-Activity Relationship; D014357:Trypsin / Q000378:metabolism
chemical_list: D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; C027538:heat-labile enterotoxin, E coli; D014357:Trypsin