title: Functional domains of Pseudomonas exotoxin identified by deletion analysis of the gene expressed in E. coli.
abstract: Pseudomonas exotoxin A is a single chain toxin with three structural domains that inhibits protein synthesis in eukaryotic cells by catalyzing ADP ribosylation of elongation factor 2. To study the function of these domains, we deleted different portions of the PE structural gene and expressed these constructs in E. coli using an inducible T7 promoter. These studies indicate that structural domain Ia is required for cell recognition, that structural domain II is required to translocate the toxin across a cellular membrane, and that structural domain III and a portion of domain Ib are required for ADP ribosylation activity. Toxin lacking domain Ia is about 100-fold less toxic to mice than intact PE and should be a useful molecule for the construction of immunotoxins.
mesh_terms: D036002:ADP Ribose Transferases; D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D001427:Bacterial Toxins; D001665:Binding Sites; D001692:Biological Transport; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D004926:Escherichia coli; D005098:Exotoxins / Q000235:genetics* / Q000633:toxicity; D010430:Pentosyltransferases / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000472:pathogenicity*; D013329:Structure-Activity Relationship; D037521:Virulence Factors; D000097668:Pseudomonas aeruginosa Exotoxin A
chemical_list: D036002:ADP Ribose Transferases; D000246:Adenosine Diphosphate Ribose; D001427:Bacterial Toxins; D005098:Exotoxins; D010430:Pentosyltransferases; D037521:Virulence Factors; D000097668:Pseudomonas aeruginosa Exotoxin A