title: The effects of physical and chemical agents on the secretion and stability of a Fusobacterium necrophorum hemolysin.
abstract: The effect of various agents as enhancers or inhibitors of hemolysin secretion by Fusobacterium necrophorum was investigated. The hemolysin secreted in phosphate buffered saline (PBS) alone was inactivated shortly after secretion. Tween-80 or albumin preserved the hemolytic activity in PBS in which cultures of F. necrophorum had been suspended. Hemoglobin was found to enhance hemolysin secretion. However, higher concentrations diminished secretion. Chloramphenicol, an inhibitor of protein synthesis, exhibited no effect on the hemolytic activity. However, the addition of sodium azide, an energy metabolic inhibitor, significantly reduced the hemolytic activity. Lower temperatures and pH above 9 and below 6 all yielded a low hemolytic activity. Cells suspended in Tween-80 prior to sonication yielded a substantial amount of extracellular hemolytic activity with low intracellular activity detected. However, cells suspended in PBS alone yielded a low extracellular activity but rather a high intracellular activity. The same spectrum of red blood cells of different species were found to be sensitive to both the extracellular and intracellular hemolysins.
authors.affiliation: Department of Veterinary Microbiology, Faculty of Agriculture, Miyazaki University, Japan.
authors.forename: K K
authors.initials: KK
authors.lastname: Amoako
authors.forename: Y
authors.initials: Y
authors.lastname: Goto
authors.forename: D L
authors.initials: DL
authors.lastname: Xu
authors.forename: T
authors.initials: T
authors.lastname: Shinjo
mesh_terms: D000418:Albumins / Q000494:pharmacology*; D001386:Azides / Q000494:pharmacology*; D003470:Culture Media / Q000737:chemistry; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005675:Fusobacterium necrophorum / Q000378:metabolism*; D006454:Hemoglobins / Q000494:pharmacology*; D006460:Hemolysin Proteins / Q000187:drug effects* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D011136:Polysorbates / Q000494:pharmacology*; D019810:Sodium Azide; D012965:Sodium Chloride / Q000494:pharmacology; D013696:Temperature
chemical_list: D000418:Albumins; D001386:Azides; D003470:Culture Media; D004791:Enzyme Inhibitors; D006454:Hemoglobins; D006460:Hemolysin Proteins; D011136:Polysorbates; D012965:Sodium Chloride; D019810:Sodium Azide