Enterotoxic activity of hemolysin BL from Bacillus cereus
Year: 1995
Type: article
Abstract: Bacillus cereus causes exotoxin-mediated diarrheal food poisoning. Hemolysin BL (HBL) is a well-characterized B. cereus toxin composed of three components (B, L1, and L2) that together possess hemolytic, cytotoxic, dermonecrotic, and vascular permeability activities. Here, we show that HBL causes fluid accumulation in ligated rabbit ileal loops at a dose of 5 micrograms of each component per loop. Maximal fluid responses occurred for combinations of all three components at > or = 25 micrograms of each component per loop. Individual components and binary combinations did not cause significant fluid accumulation at 25 micrograms of each component. Specific antisera to HBL components inhibited the fluid accumulation response of crude culture supernatant from B. cereus F837/76. These antisera were tested against an antiserum to a partially characterized multicomponent diarrheal toxin described previously by Thompson et al. (N. E. Thompson, M. J. Ketterhagen, M. S. Bergdoll, and E. J. Shantz, Infect. Immun. 43:887-894, 1984). Immunoblot and immunoprecipitation analyses indicate that HBL and that toxin are identical. These results confirm previous speculation that HBL is a tripartite enterotoxin that, as for all of its other known activities, requires all three components for maximal activity.
Source: Infection and Immunity
Authors: D J Beecher, J L Schoeni, A C Wong
Institution: University of Wisconsin–Madison
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2118739457