HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Beecher, D. J. Articles by Wong, A. C.L. Search for Related Content PubMed PubMed Citation Articles by Beecher, D. J. Articles by Wong, A. C.L. Social Bookmarking                      What's this?

Volume 272, Number 1, Issue of January 3, 1997 pp. 233-239
©1997 by The American Society for Biochemistry and Molecular Biology, Inc.

---

Tripartite Hemolysin BL from Bacillus cereus
HEMOLYTIC ANALYSIS OF COMPONENT INTERACTIONS AND A MODEL FOR ITS CHARACTERISTIC PARADOXICAL ZONE PHENOMENON

(Received for publication, June 25, 1996, and in revised form, October 11, 1996)

From the Food Research Institute, Department of Food Microbiology and Toxicology, University of Wisconsin, Madison, Wisconsin 53706

Hemolysin BL (HBL) is a unique membrane-lytic toxin from Bacillus cereus composed of three distinct proteins, designated B, L₁, and L₂. HBL produces a paradoxical zone phenomenon in gel diffusion assays in sheep blood agar. Lysis does not begin immediately adjacent to the source of diffusion; rather, it begins several millimeters away. Cells near the source and at intersections of lysis zones remain intact longer. Here, we developed a spectrophotometric hemolysis assay system that measures the activities of the individual HBL components and used it to analyze the mechanisms of hemolysis and the paradoxical zone phenomenon. The B component was rate-limiting, and erythrocytes were slowly primed by B at an optimal concentration of about 1.3 nM to rapid lytic action by the combination of the L components (L₁₊₂). All of the individual components bound to cells independently, and membrane-associated HBL components were neutralized by specific antibodies, suggesting that lysis was caused by formation of a membrane attack complex on the cell surface. Osmotic protection experiments indicate a colloid osmotic lysis mechanism. Concentrations of the B component above 1.3 nM caused inhibition of L₁-mediated lysis, and L₁ inhibited the priming reaction of B over a similar concentration range. From analyses of spectrophotometric and diffusion assays we constructed a basic model for the interactions between HBL components and for the paradoxical zone phenomenon in blood agar. In the latter, areas of slow lysis near diffusion sources are caused primarily by the accumulation of inhibitory levels of L₁ reached before cells are primed by B.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				K. M. Gray, P. P. Banada, E. O'Neal, and A. K. Bhunia Rapid Ped-2E9 Cell-Based Cytotoxicity Analysis and Genotyping of Bacillus Species J. Clin. Microbiol., December 1, 2005; 43(12): 5865 - 5872. [Abstract] [Full Text] [PDF]

				T. Lindback, A. Fagerlund, M. S. Rodland, and P. E. Granum Characterization of the Bacillus cereus Nhe enterotoxin Microbiology, December 1, 2004; 150(12): 3959 - 3967. [Abstract] [Full Text] [PDF]

				J. Brillard and D. Lereclus Comparison of cytotoxin cytK promoters from Bacillus cereus strain ATCC 14579 and from a B. cereus food-poisoning strain Microbiology, August 1, 2004; 150(8): 2699 - 2705. [Abstract] [Full Text] [PDF]

				M.-H. Guinebretiere, V. Broussolle, and C. Nguyen-The Enterotoxigenic Profiles of Food-Poisoning and Food-Borne Bacillus cereus Strains J. Clin. Microbiol., August 1, 2002; 40(8): 3053 - 3056. [Abstract] [Full Text] [PDF]

				H. Abriouel, M. Maqueda, A. Galvez, M. Martinez-Bueno, and E. Valdivia Inhibition of Bacterial Growth, Enterotoxin Production, and Spore Outgrowth in Strains of Bacillus cereus by Bacteriocin AS-48 Appl. Envir. Microbiol., March 1, 2002; 68(3): 1473 - 1477. [Abstract] [Full Text] [PDF]

				D. J. Beecher and A. C. L. Wong Cooperative, synergistic and antagonistic haemolytic interactions between haemolysin BL, phosphatidylcholine phospholipase C and sphingomyelinase from Bacillus cereus Microbiology, December 1, 2000; 146(12): 3033 - 3039. [Abstract] [Full Text] [PDF]

				D. J. Beecher and A. C. L. Wong Tripartite haemolysin BL: isolation and characterization of two distinct homologous sets of components from a single Bacillus cereus isolate Microbiology, June 1, 2000; 146(6): 1371 - 1380. [Abstract] [Full Text]

				B. M. Prüß, R. Dietrich, B. Nibler, E. Märtlbauer, and S. Scherer The Hemolytic Enterotoxin HBL Is Broadly Distributed among Species of the Bacillus cereus Group Appl. Envir. Microbiol., December 1, 1999; 65(12): 5436 - 5442. [Abstract] [Full Text]

				R. Dietrich, C. Fella, S. Strich, and E. Märtlbauer Production and Characterization of Monoclonal Antibodies against the Hemolysin BL Enterotoxin Complex Produced by Bacillus cereus Appl. Envir. Microbiol., October 1, 1999; 65(10): 4470 - 4474. [Abstract] [Full Text]

				M. C. Callegan, B. D. Jett, L. E. Hancock, and M. S. Gilmore Role of Hemolysin BL in the Pathogenesis of Extraintestinal Bacillus cereus Infection Assessed in an Endophthalmitis Model Infect. Immun., July 1, 1999; 67(7): 3357 - 3366. [Abstract] [Full Text] [PDF]