Daniel M. Keller

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A new member of the staphylococcal bi-component leucotoxins family, LukE (32 kDa) and LukD (34.3 kDa) has been characterized from Staphylococcus aureus strain Newman. LukE was 58-68% identical with the class S proteins, whereas LukD was 71-77% identical with the class F proteins of the family. A partial immunoreactivity with the various affinity-purified(More)
The staphylococcal alpha-toxin and bipartite leucotoxins belong to a single family of pore-forming toxins that are rich in beta-strands, although the stoichiometry and electrophysiological characteristics of their pores are different. The different known structures show a common beta-sandwich domain that plays a key role in subunit-subunit interactions,(More)
BACKGROUND Mesangial cell proliferation is a characteristic feature of IgA nephropathy and many other forms of glomerulonephritis. Recent clinical studies have shown that dietary fish oil supplementation retards renal disease progression in patients with IgA nephropathy. The mechanism by which this effect occurs is unknown. METHODS The anti-Thy 1.1 (ATS)(More)
Staphylococcus aureus is an opportunistic commensal bacterium that mostly colonizes the skin and soft tissues. The pathogenicity of S. aureus is due to both its ability to resist antibiotics, and the production of toxins. Here, we characterize a group of genes responsible for toxin production and antibiotic resistance of S. aureus strains isolated from(More)
UNLABELLED α-Defensins produced by neutrophils are important effector molecules of the innate immune system. In addition to their microbicidal effects, α-defensins have the ability to neutralize bacterial toxins. Panton-Valentine leukocidin (PVL) is the hallmark of community-acquired methicillin-resistant Staphylococcus aureus. Staphylococcus aureus that(More)
Staphylococcus aureus is responsible for severe bacterial infections in hospitals and healthcare facilities. It produces single and bicomponent toxins (leukotoxins and hemolysins) that hinder innate immune function. Leukotoxin subunits bind to leukocyte cell membrane thus inducing transmembrane pores and subsequently, cell lysis. Leukotoxin LukE/D is a(More)
OBJECTIVE Staphylococcus lugdunensis is a coagulase-negative staphylococcus that displays an unusually high virulence rate close to that of Staphylococcus aureus. It also shares phenotypic properties with S. aureus and several studies found putative virulence factors. The objective of the study was to describe the clinical manifestations of S. lugdunensis(More)
Hydrostatic pressure was found to cause a marked narrowing of pH ranges for growth and reductions in growth yields for a variety of bacteria. In many cases, reduced yields under pressure could be directly related to increased sensitivities to metabolic acids that accumulated in the enclosed culture vessels used. Magnesium and calcium ions partially reversed(More)