title: Correlation between Congo red binding and contact haemolysin production in Shigella species.
abstract: Haemolytic strains of Shigella dysenteriae type 1, Shigella flexneri, Shigella boydii and Shigella sonnei cultured on Congo red agar produced pigmented colonies (Pcr+) whereas nonhaemolytic strains produced white colonies and did not bind Congo red (Pcr-). S. flexneri-1 haemolysin negative mutant (lacking plasmid) of haemolysin positive prototroph also did not bind Congo red and produced nonpigmented colonies. Among the twelve strains of Shigella included in this study, the characteristics of Congo red binding, plasmid profile and haemolytic activity appeared to be correlated. Congo red binding occurred comparatively more by haemolysin-producing strains. Congo red binding can be used as a quick and reliable method for virulence traits of pathogens, including haemolysin activity.
authors.affiliation: Department of Microbiology, Panjab University, Chandigarh, India.
authors.forename: K
authors.initials: K
authors.lastname: Sharma
authors.forename: P
authors.initials: P
authors.lastname: Rishi
authors.forename: J S
authors.initials: JS
authors.lastname: Grewal
authors.forename: S
authors.initials: S
authors.lastname: Ram
authors.forename: R P
authors.initials: RP
authors.lastname: Tiwari
mesh_terms: D001422:Bacterial Adhesion; D003224:Congo Red / Q000378:metabolism*; D004269:DNA, Bacterial / Q000032:analysis; D004587:Electrophoresis, Agar Gel; D006460:Hemolysin Proteins / Q000378:metabolism*; D010957:Plasmids; D012760:Shigella / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D012761:Shigella boydii / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity; D012762:Shigella dysenteriae / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity; D012763:Shigella flexneri / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity; D012764:Shigella sonnei / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity; D014774:Virulence
chemical_list: D004269:DNA, Bacterial; D006460:Hemolysin Proteins; D003224:Congo Red