Thirty-six ruminant isolates of Chlamydia psittaci, previously classified as invasive or non-invasive in a mouse model of virulence, were compared by analysing AluI restriction patterns of the major outer-membrane protein (MOMP) gene after DNA amplification by the polymerase chain reaction. The 24 invasive isolates, although from various origins, all belonged to serotype 1 and represented a str...

The ability of the housefly to carry viable Chlamydia trachomatis and to transmit a chlamydial ocular infection was studied under laboratory conditions. After feeding flies (Musca domestica) on suspensions of egg yolk sac infected with C. trachomatis serotypes A or B (responsible for hyperendemic trachoma) the agents were reisolated from flies' intestines for up to 6 hours and from their legs a...

The obligate intracellular nature of chlamydiae presents challenges to the characterization of its phages, which are potential tools for a genetic transfer system. An assay for phage infectivity is described, and the infectious properties of phage Chp2 were determined.

Chlamydia pneumoniae (C. pneumoniae) is a common human pathogen causing a range of respiratory diseases from pharyngitis to pneumonia. Even though the majority of diseases are mild or even asymptomatic, persistent C. pneumoniae infections have been associated with chronic diseases such as asthma and atherosclerosis which represent significant health problems in many countries. Consequently, the...

Chlamydiae are obligate intracellular pathogens that exhibit an extensive intracellular developmental cycle in vivo. Clinical treatment of chlamydial infection is typically initiated upon occurrence of symptomatology and is directed against an asynchronous population of different chlamydial developmental forms. Pharmacodynamics of antichlamydial drugs are predominantly characterized by MICs; ho...

Chlamydiae are obligate intracellular bacteria, developing inside host cells within chlamydial inclusions. From these inclusions, the chlamydiae secrete proteins into the host cell cytoplasm. A pathway through which secreted proteins can be delivered is the type III secretion system (T3SS). The T3SS is common to several gram-negative bacteria and the secreted proteins serve a variety of functio...

The process of chlamydial cell division has not been thoroughly investigated. The lack of detectable peptidoglycan and the absence of an FtsZ homolog within chlamydiae suggest an unusual mechanism for the division process. Our laboratory has identified an antigen (SEP antigen) localized to a ring-like structure at the apparent septum within dividing chlamydial reticulate bodies (RB). Antisera d...

Sexually transmitted Chlamydia trachomatis is an extremely common infection and often leads to serious complications including infertility and pelvic inflammatory syndrome. Several broad-spectrum antibiotics are currently used to treat C. trachomatis. Although effective, they also kill beneficial vaginal lactobacilli. Two N-acylhydrazones, CF0001 and CF0002, have been shown previously to inhibi...

An in vitro model of persistent infection of mouse fibroblasts (McCoy cells) with a trachoma strain (G17) of Chlamydia trachomatis has been developed. Persistently infected cultures were established by infecting McCoy cells with high multiplicities of chlamydiae. After the first cycle of chlamydial replication, the host cells multiplied more rapidly than the parasites, so that the fraction of i...