Insertional inactivation of hblC encoding the L2 component of Bacillus cereus ATCC 14579 haemolysin BL strongly reduces enterotoxigenic activity, but not the haemolytic activity against human erythrocytes.
Haemolysin BL (HBL) is a Bacillus cereus toxin composed of a binding component, B, and two lytic components, L1 and L2. HBL is also the enterotoxin responsible for the diarrhoeal food poisoning syndrome caused by several strains of B. cereus. The three genes encoding the HBL components constitute an operon and are transcribed from a promoter 608 bp upstream of the hblC translational start site. The first gene of the hbl operon, hblC, in the B. cereus type strain, ATCC 14579, was inactivated in this study. Inactivation of hblC strongly reduced both the enterotoxigenic activity of B. cereus ATCC 14579 and the haemolytic activity against sheep erythrocytes, while maintaining full haemolytic activity against human erythrocytes.
Lindbäck
Toril
T
Biotechnology Centre of Oslo and School of Pharmacy, Department of Microbiology, University of Oslo, PO Box 1125 Blindern, N-0349 Oslo, Norway1.
Økstad
Ole Andreas
OA
Biotechnology Centre of Oslo and School of Pharmacy, Department of Microbiology, University of Oslo, PO Box 1125 Blindern, N-0349 Oslo, Norway1.
Rishovd
Anne-Lise
AL
Biotechnology Centre of Oslo and School of Pharmacy, Department of Microbiology, University of Oslo, PO Box 1125 Blindern, N-0349 Oslo, Norway1.
Kolstø
Anne-Brit
AB
Biotechnology Centre of Oslo and School of Pharmacy, Department of Microbiology, University of Oslo, PO Box 1125 Blindern, N-0349 Oslo, Norway1.
D000818:Animals; D001409:Bacillus cereus / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002645:Chickens; D002522:Chlorocebus aethiops; D004768:Enterotoxins / Q000378:metabolism*; D004912:Erythrocytes; D006460:Hemolysin Proteins / Q000378:metabolism*; D006461:Hemolysis; D006736:Horses; D006801:Humans; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D012329:RNA, Bacterial / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D012756:Sheep; D014158:Transcription, Genetic; D014709:Vero Cells
D001426:Bacterial Proteins; D004768:Enterotoxins; D006460:Hemolysin Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; C083961:hemolysin BL protein, Bacillus