title: Short report: high prevalence of serine protease autotransporter cytotoxins among strains of enteroaggregative Escherichia coli.
abstract: Enteroaggregative Escherichia coli (EAEC) pathogenesis is thought to comprise intestinal colonization followed by the release of enterotoxins and cytotoxins. Here, we use a polymerase chain reaction (PCR) to determine the prevalence of 10 genes encoding serine protease autotransporter toxins (SPATEs) in a collection of clinical EAEC isolates. Eighty-six percent of EAEC strains harbored genes encoding one or more class I cytotoxic SPATE proteins (Pet, Sat, EspP, or SigA). Two Class II, non-cytotoxic, SPATE genes were found among EAEC strains: pic and sepA, each originally described in Shigella flexneri 2a. Using a multiplex PCR for five SPATE genes (pet, sat, sigA, pic, and sepA), we found that most of the Shigella isolates also harbored more than one SPATE, whereas members of most other E. coli pathotypes rarely harbored a cytotoxic SPATE gene. SPATEs may be relevant to the pathogenesis of both EAEC and Shigella spp.
authors.affiliation: Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Nadia
authors.initials: N
authors.lastname: Boisen
authors.forename: Fernando
authors.initials: F
authors.lastname: Ruiz-Perez
authors.forename: Flemming
authors.initials: F
authors.lastname: Scheutz
authors.forename: Karen A
authors.initials: KA
authors.lastname: Krogfelt
authors.forename: James P
authors.initials: JP
authors.lastname: Nataro
mesh_terms: D001427:Bacterial Toxins / Q000235:genetics* / Q000378:metabolism; D003603:Cytotoxins / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods; D015995:Prevalence; D012697:Serine Endopeptidases / Q000235:genetics* / Q000378:metabolism; D012760:Shigella / Q000201:enzymology / Q000235:genetics / Q000472:pathogenicity; D037521:Virulence Factors
chemical_list: D001427:Bacterial Toxins; D003603:Cytotoxins; D029968:Escherichia coli Proteins; D037521:Virulence Factors; D012697:Serine Endopeptidases