Members of the species chlamydia are characterised by their obligate intracellular life cycle. The genus comprises three species; Chlamydia trachomatis, Chlamydia psittaci and Chlamydia pneumoniae. C. pneumoniae causes acute respiratory infections in humans. This organism has only recently been shown to warrant its own species classification within the chlamydial genus based on immunological, u...

We cloned and sequenced the gene encoding the major outer membrane protein (MOMP) of two Chlamydia psittaci strains, guinea pig inclusion conjunctivitis (GPIC) strain 1, and meningopneumonitis (Mn) strain Cal-10. Intraspecies alignment of the two C. psittaci MOMP genes revealed 80.6% similarity, and interspecies comparison of C. trachomatis and C. psittaci MOMP genes yielded about 68% similarit...

Reports on the prevalence of abortion due to Chlamydia psittaci (Chlamydophila abortus) in Kerala have indicated a need for the in depth study of the organism. To unearth differences among the isolates of Chlamydia psittaci, at molecular level, restriction enzyme analysis of genomic DNA and plasmid profiling were carried out. Four isolates from four different sources were used in this study. DN...

The primary sequence of the small cysteine-rich protein (EnvA) of Chlamydia psittaci 6BC has been shown to possess a potential lipid modification/signal peptidase II-processing site, and the mature protein was labeled by a [3H]palmitic acid precursor. We further characterized the mature EnvA, showing that it lacks the N-terminal methionine of the primary peptide, is hydrophobic despite a peptid...

During the summer of 1986, more than 400 California gulls (Larus californicus) and ring-billed gulls (Larvus delawarensis), primarily fledglings, died on an island in Lake Sakakawea near New Town, North Dakota (USA). Mortality was attributed largely to chlamydiosis. Necropsy findings in nine carcasses included splenomegaly (n = 9), hepatomegaly (n = 4), and pericarditis (n = 1). Livers from thr...

In a flock of 12,000 bobwhite quail (Colinus virginianus) and 7200 chukar partridge (Alectoris chukar), the owner had 100% morbidity and 40%-50% mortality in birds between the ages of 2 and 4 wk. Affected birds were stunted and anorexic and had yellow/green diarrhea. Two- and 4-wk-old birds submitted for necropsy all had slight nasal discharge. Histopathologic examination revealed mild (bobwhit...

Chlamydia psittaci is an obligately intracellular Gram-negative bacterium causing respiratory disease (chlamydiosis) or asymptomatic carriage in birds. C. psittaci is a zoonotic agent causing psittacosis or parrot fever in humans. Vertical and/or horizontal transmission via eggs might have serious repercussions on the C. psittaci infection status of poultry flocks and thus on zoonotic risk for ...

Chlamydia psittaci is an avian pathogen and zoonotic agent of atypical pneumonia. The most pathogenic C. psittaci strains cluster into the 6BC clade, predicted to have recently emerged globally. Exposure to infected parrots is a risk factor with limited evidence also of an indirect exposure risk. Genome sequencing was performed on six Australian human and a single avian C. psittaci strain isola...