title: Novel observation of hot-cold-hot hemolysis exhibited by group B streptococci.
abstract: Six human isolates of group B streptococci (GBS) were cultured on blood agar anaerobically at 37 degrees C for 18 h and then at 4 degrees C for 6 h and reincubated anaerobically at 37 degrees C for 6 h. Three of the strains showed a marked enlargement of the hemolysis zone compared with that obtained after hot-only (37 degrees C for 18 h) or hot-cold (37 degrees C for 18 h and then 4 degrees C for 6 h) treatment. Subsequent broth culture experiments revealed that enhanced hemolytic activity due to hot-cold-hot treatment was observed in all 6 GBS strains when cultured in the presence of starch.
authors.affiliation: Department of Bacteriology and Pathology, Kanagawa Prefectural Public Health Laboratory, Nakao 1-1-1, Asahi-ku, Yokohama 241-0815, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Okazaki
authors.forename: Ro
authors.initials: R
authors.lastname: Osawa
authors.forename: Rieko
authors.initials: R
authors.lastname: Suzuki
authors.forename: Takayasu
authors.initials: T
authors.lastname: Nikkawa
authors.forename: Robert A
authors.initials: RA
authors.lastname: Whiley
mesh_terms: D006461:Hemolysis / Q000502:physiology*; D006358:Hot Temperature; D006801:Humans; D013292:Streptococcus agalactiae / Q000502:physiology*; D013696:Temperature