title: Evolutionary perspective on a composite Shigella flexneri 2a virulence plasmid-borne locus comprising three distinct genetic elements.
abstract: Nucleotide sequence analysis of a Shigella flexneri 2a virulence plasmid-borne locus revealed that it comprised three distinct genetic elements: a stretch of colicin 1a/1b-linked sequence, a truncated IS911 element, and a third element containing two ORFs that shared a high level of similarity to a Salmonella-specific chromosomal sequence. Examination of other known IS911-like sequences showed that these sequences also were frequently associated with other accessory elements and appeared to be prone to partial deletion events. Analysis of the data led to a model of the evolution of this unusual composite locus.
authors.affiliation: Department of Microbiology, Monash University, Melbourne, Vic, Australia. Kumar.Rajakumar@med.monash.edu.au
authors.forename: K
authors.initials: K
authors.lastname: Rajakumar
authors.forename: F
authors.initials: F
authors.lastname: Luo
authors.forename: C
authors.initials: C
authors.lastname: Sasakawa
authors.forename: B
authors.initials: B
authors.lastname: Adler
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003087:Colicins / Q000235:genetics; D004251:DNA Transposable Elements; D019143:Evolution, Molecular; D008957:Models, Genetic; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009154:Mutation; D016366:Open Reading Frames; D010957:Plasmids / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012763:Shigella flexneri / Q000235:genetics* / Q000472:pathogenicity*
chemical_list: D003087:Colicins; D004251:DNA Transposable Elements