Providencia alcalifaciens in a patient with a staghorn calculus: a novel presentation.

A member of the Enterobacteriaceae family, Providencia alcalifaciens is typically recognized as a source of gastrointestinal illness. Although its pathogenicity is not well known, many studies have suggested its mechanism of action involves the invasion of the intestinal mucosal layer. Although P.

Differential regulation of Spa47 ATPase activity by a native C-terminal product of Spa33.

is a Gram-negative bacterial pathogen that relies on a single type three secretion system (T3SS) as its primary virulence factor. The T3SS includes a highly conserved needle-like apparatus that directly injects bacterial effector proteins into host cells, subverting host cell function, initiating infection, and circumventing resulting host immune responses. Recent findings have located the T3SS ATPase Spa47 to the base of the T3SS apparatus and have correlated its catalytic function to apparatus formation, protein effector secretion, and overall pathogen virulence.