title: Evolution and structure of two ADP-ribosylation enterotoxins, Escherichia coli heat-labile toxin and cholera toxin.
abstract: Nucleotide sequence comparisons of the heat-labile enterotoxin (LTh) genes of E. coli pathogenic for humans with cholera toxin (CT) genes suggest that the two toxin genes have evolved from a common ancestry by a series of single base changes, while conserving the catalytic fragment A1 (ADP-ribose transferase). Based on the local hydrophilicity profiles of LTh and CT peptides, a transmembrane segment appears to be present in A1 in both toxins.
mesh_terms: D000595:Amino Acid Sequence; D001427:Bacterial Toxins / Q000235:genetics*; D001483:Base Sequence; D002772:Cholera Toxin / Q000235:genetics*; D004768:Enterotoxins / Q000235:genetics*; D004926:Escherichia coli; D029968:Escherichia coli Proteins; D008958:Models, Molecular; D009713:Nucleotidyltransferases / Q000378:metabolism*; D009876:Operon; D011065:Poly(ADP-ribose) Polymerases
chemical_list: D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D002772:Cholera Toxin; C027538:heat-labile enterotoxin, E coli; D011065:Poly(ADP-ribose) Polymerases; D009713:Nucleotidyltransferases