The thermostable direct hemolysin produced by Vibrio parahaemolyticus showed cytotoxic activity on FL cells derived from human amniotic membrane. Scanning electron micrographs of the whole cells showed that the microvilli on the cell surface decreased in number and changed in shape on treatment with the hemolysin. Most of the microvilli disappeared before death of the cells, as judged from the ...

Thermostable direct hemolysin purified from cultured filtrates of a pathogenic strain of Vibrio parahaemolyticus (1) has been reported to have potent cardiotoxic and hemolytic activities (2, 3). Intravenous injection of small doses (10 to 20 ug/kg) of hemolysin killed the rats within several hr. Electrocardiograms of rats after administration (i.v.) of hemolysin showed significant changes due t...

BACKGROUND Serratia marcescens, a frequent agent of catheterization-associated bacteriuria, strongly adheres to human bladder epithelial cells in culture. The epithelium normally provides a barrier between lumal organisms and the interstitium; the tight adhesion of bacteria to the epithelial cells can lead to internalization and subsequent lysis. However, internalisation was not shown yet for S...

The contribution of the cell-bound hemolysin of Serratia marcescens to uropathogenicity was studied in an experimental urinary tract infection in rats. The strain carrying the Serratia hemolysin colonized the urinary tract more and lead to a stronger inflammatory response compared to the isogenic hemolysin negative strain.

The bacteriocin and hemolysin produced by a Streptococcus faecium strain were partially separated after gel filtration on Ultrogel AcA-22. The molecular weight of bacteriocin was approximately 300,000, and that of hemolysin was 220,000. Non-bacteriocinogenic mutants retained the hemolytic activity. Production of hemolysin required glucose, whereas that of bacteriocin did not.

It is shown that Serratia marcescens exports a hemolysin to the cell surface and secretes it to the extracellular space. Escherichia coli containing the cloned hemolysin genes shlA and shlB exported and secreted the S. marcescens hemolysin. A nonhemolytic secretion-incompetent precursor of the hemolysin, designated ShlA*, was synthesized in a shlB deletion mutant and accumulated in the periplas...

Some properties of the cell-free and cell-associated hemolysins of Escherichia coli were studied. Several strains of E. coli that were isolated from intestines of pigs with edema disease produce large quantities of cell-free hemolysin when grown in the presence of an extract of meat. The component of meat that stimulates production of cell-free hemolysin is not extracted by lipid solvents and i...

Sixty-four verotoxin-producing (VT+) Escherichia coli strains were analyzed for VT1- and VT2-specific DNA sequences and for production of hemolysin. Strains of human origin were of the following serotypes: O157:H7 or H-, O111:H8 or H-, O26:H11, O114:H4, and rough:H7. Strains of serotypes O157:H7, O113:H21, O116:H21, and rough:H- were from cattle, while those of serotype O139:K12:H1 were from pi...

We examined the effects of human low density lipoprotein (LDL) and oxidized LDL (Ox-LDL) on the cytotoxic activity of Asp-hemolysin from Aspergillus fumigatus Fresenius-Muramatsu strain to mouse peritoneal macrophages (M phi). The inhibitory effects of LDL and Ox-LDL on the cytotoxic activity of Asp-hemolysin to M phi increased in a dose-dependent manner, and the effect of Ox-LDL was greater th...

El Tor and non-O1 strains of Vibrio cholerae were analyzed to determine whether synthesis of secreted hemolysin was influenced by the concentration of iron in the medium. Synthesis of hemolysin was found to be iron regulated in both El Tor and non-O1 isolates. Increased levels of hemolytic activity were detected in supernatants of iron-starved cells. Spontaneous hemolysin-deficient mutants of o...