Novel observation of hot-cold-hot hemolysis exhibited by group B streptococci.
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.
Okazaki
Norio
N
Department of Bacteriology and Pathology, Kanagawa Prefectural Public Health Laboratory, Nakao 1-1-1, Asahi-ku, Yokohama 241-0815, Japan.
Osawa
Ro
R
Suzuki
Rieko
R
Nikkawa
Takayasu
T
Whiley
Robert A
RA
D006461:Hemolysis / Q000502:physiology*; D006358:Hot Temperature; D006801:Humans; D013292:Streptococcus agalactiae / Q000502:physiology*; D013696:Temperature