title: Detection of haemolytic activity of campylobacters by agarose haemolysis and microplate assay.
abstract: There are several methods for the detection of haemolytic activity in campylobacters. However, we found the haemolytic effect of campylobacters on conventional blood agar plates to be variable, inconsistent and difficult to interpret. Blood agarose plates showed campylobacter haemolytic activity more clearly. The incubation conditions (temperature and gaseous) appear to be important for the expression of this activity. Ninety four percent of the Campylobacter isolates examined were found to be haemolytic by the microplate assay with minimal haemolytic units that ranged from 1 to 64. Haemolytic activity was detected only from live bacterial cultures and not from any of the 50 bacterial culture supernates, which suggests that campylobacters may possess a cell-associated haemolysin. The identification of such haemolytic activity in a large number of campylobacters (94%) suggests its potential role as a virulence factor in campylobacter gastroenteritis.
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: S T
authors.initials: ST
authors.lastname: Tay
authors.forename: S
authors.initials: S
authors.lastname: Devi
authors.forename: S D
authors.initials: SD
authors.lastname: Puthucheary
authors.forename: I M
authors.initials: IM
authors.lastname: Kautner
mesh_terms: D000818:Animals; D002167:Campylobacter / Q000378:metabolism* / Q000472:pathogenicity; D002417:Cattle; D003470:Culture Media; D006461:Hemolysis; D006358:Hot Temperature; D006801:Humans; D011112:Polymyxin B / Q000494:pharmacology; D011817:Rabbits; D012685:Sepharose; D012756:Sheep; D014774:Virulence
chemical_list: D003470:Culture Media; D012685:Sepharose; D011112:Polymyxin B