Leptospirosis is a spirochetal zoonosis that causes an acute febrile systemic illness in humans. Leptospira sp. hemolysins have been shown to be virulence factors for the pathogenesis of leptospirosis. Previously, we cloned a hemolysin SphH of Leptospira interrogans serovar lai, a homologue of L. borgpetersenii sphingomyelinase (SphA), from a genomic library (S. H. Lee, K. A. Kim, Y. K. Kim, I....

Bacillus cereus causes a highly fulminant endophthalmitis which usually results in blindness. We previously concluded that hemolysin BL (HBL), a tripartite necrotizing pore-forming toxin, is a probable endophthalmitis virulence factor because it is highly toxic to retinal tissue in vitro and in vivo. We also determined that B. cereus produces additional retinal toxins that might contribute to v...

Group B Streptococcus (GBS), a common commensal of the female genital tract, is the leading cause of invasive infections in neonates. Expression of major GBS virulence factors, such as the hemolysin operon cyl, is regulated directly at the transcriptional level by the CovSR two-component system. Using a random genetic approach, we identified a multi-spanning transmembrane protein, Abx1, essenti...

Liu, Pinghui V. (University of Louisville, Louisville, Ky.). Factors that influence toxigenicity of Pseudomonas aeruginosa. J. Bacteriol. 88:1421-1427. 1964.-Hemolysin, lecithinase, and protease of Pseudomonas aeruginosa were produced with cellophane-covered plates and completely synthetic agar of simple composition containing alpha-alanine, aspartic acid, glutamic acid, glucose, and salts. The...

We present a novel NMR-based study of the molecular aspects of the "attack" on human red blood cells (RBCs) by growing bacteria. Staphylococcus aureus expresses virulence factors, including alpha-hemolysin, which contribute to the clinical condition known as septic shock. alpha-Hemolysin is a pore-forming toxin and its secretion increases the permeability of a range of mammalian cell types infe...

BACKGROUND Candida spp. is frequently isolated from cases of vulvovaginal candidiasis and catheter associated UTI. C.albicans is the most frequently isolated species but non-albicans species of candida are gaining clinical significance. OBJECTIVES To compare the virulence factors like biofilm production, phospholipase and hemolytic activity in C.albicans with that of non albicans species of c...

The hemolytic phenotype in Escherichia coli is determined by four genes. Two (hlyC and hlyA) determine the synthesis of a hemolytically active protein which is transported across the cytoplasmic membrane. The other two genes (hlyBa and hlyBb) encode two proteins which are located in the outer membrane and seem to form a specific transport system for hemolysin across the outer membrane. The prim...

Secretion of the 107-kDa hemolysin A (HlyA) from Escherichia coli is mediated by the membrane proteins hemolysin B and hemolysin D. Hemolysin B is a member of the so-called ATP binding cassette transporter superfamily, which includes the multidrug resistance P-glycoprotein, the cystic fibrosis CFTR protein, and the major histocompatibility complex-associated transporter of antigenic peptides. R...

We found that virulent hemolysin-producing (Hly+) Listeria monocytogenes strains inhibit antigen processing and presentation when added to macrophages in vitro. A virulent Hly- bacteria caused little or no inhibition. Live Hly+ bacteria inhibited presentation of both heat-killed L. monocytogenes and ovalbumin. Several observations indicate that hemolysin produced by intracellular bacteria was r...