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PubMed2003

Seroprevalence of Coxiella burnetii infections among cats in different living environments.

The seroprevalence of Coxiella burnetii infection among pet cats in Japan and Korea and stray cats in Japan was investigated by an indirect fluorescent antibody technique and PCR test. Forty-four (14.2%) of 310 pet cats in Japan were seropositive, as were 15 (41.7%) of 36 stray cats in Japan and 10 (8.6%) of 116 pet cats in Korea. The antibody positive rate in stray cats was significantly higher than that in pet cats, but there was no correlation between the rates in Japanese and Korean pet cats. In this study, the prevalence of C. burnetii infection among cats in different living environments was found and it is difficult to deny that stray cats would be one of the important sources of infection for human Q fever.

Animals↗

PubMed1993

Immunocytochemical demonstration of Coxiella burnetii antigen in the fetal placenta of naturally infected sheep and cattle.

Coxiella burnetii antigen was demonstrated immunocytochemically in the placental tissues of aborted fetuses from four cows and two ewes and from one full-term calf. Antigen was observed in cytoplasmic vacuoles of trophoblasts, especially along the base of the chorionic villi. Positive trophoblasts were of normal size or exhibited striking cytoplasmic enlargement. Antigen was also demonstrated in neutrophils, degenerated cells and extracellularly in the intervillous spaces. The chorioallantoic connective tissue, allantoic surface and fetal tissues were devoid of C. burnetii antigen. Ovine placentas showed strong coxiella-specific staining and histological lesions characterized by moderate to severe, multifocal, necrotizing and purulent inflammation. In bovine placentas, the number of immunopositive cells varied from few to moderate and changes were mild or absent. Placental vasculitis consisting of infiltrating mononuclear cells, neutrophils or eosinophils was observed in both of the ovine and two of the bovine fetuses. In addition, a few intravascular thrombi were observed in one ovine and one bovine placenta. Thus the ovine coxiellosis cases were associated with an abundant accumulation of C. burnetii antigen and with severe necrotizing purulent placentitis, whereas in bovine coxiellosis the lesions were mild or absent and the number of organisms demonstrated immunocytochemically was much smaller. These results suggest a relation between species, lesion severity and weight of infection.

Animals↗

PubMed1971

Biochemistry of Coxiella burnetii: Embden-Meyerhof pathway.

Purified preparations of Coxiella burnetii were examined for enzymes of the glycolytic pathway. Glucose-phosphate isomerase, fructose-1,6-diphosphatase, aldolase, glyceraldehyde-3-phosphate dehydrogenase, and pyruvate kinase were shown to be present in C. burnetii extracts. Heat-killed C. burnetii purified with normal yolk sacs demonstrated no activity after disruption. Aldolase was shown to be of the class II type by complete inhibition of activity in the presence of 8 x 10(-3)m ethylenediaminetetraacetic acid. The host enzyme activity (normal and infected yolk sacs) was not affected by the same treatment. When cellulose acetate electrophoresis was performed on the extracts, aldolase from both normal and infected yolk sacs exhibited five isozyme bands, whereas aldolase from the C. burnetii extract appeared as a single band.

Acetates↗

PubMed1994

Coxiella burnetii phase I and II proteins studied by SDS-page.

Coxiella burnetii cells in both phase I and II reveal in sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE) similar protein profiles with only small differences. C. burnetii protein profile in SDS-PAGE depended on the method of purification of C. burnetii cells from chick embryo yolk sacs. Immune mouse sera against C. burnetii phase I cells recognized in phase I and II cell protein profiles mainly the 61 K and 29 K proteins by the immunoblot method. Hyperimmune mouse and rabbit sera against phase I and II cells reacted in different way with phase I and II cells. Sera against phase I cells recognized in both phase I and II profiles more protein bands than sera against phase II cells. Thus phase I LPS present in phase I cells exerted adjuvant effect on the antibody response in animals immunized with phase I cells.

Animals↗

PubMed2005

Identification and characterization of an immunodominant 28-kilodalton Coxiella burnetii outer membrane protein specific to isolates associated with acute disease.

Coxiella burnetii causes acute Q fever in humans and occasional chronic infections that typically manifest as endocarditis or hepatitis. Isolates associated with acute disease were found to be distinct from a group of chronic disease isolates by a variety of biochemical parameters and in a guinea pig fever model of acute disease, suggesting a difference in virulence potential. We compared antigenic polypeptides among C. burnetii isolates and found an immunodominant 28-kDa protein in acute group isolates but not in chronic group isolates (T. Ho, A. Hotta, G. Q. Zhang, S. V. Nguyen, M. Ogawa, T. Yamaguchi, H. Fukushi, and K. Hirai, Microbiol. Immunol. 42:81-85, 1998). In order to clone the adaA gene, the N-terminal amino acid sequence of adaA was determined and a 59-bp fragment was amplified from Nine Mile phase I DNA by PCR. The putative gene fragment was used to screen a lambda ZAP II genomic DNA library, and an open reading frame expressing a 28-kDa immunoreactive protein was identified. Sequence analysis predicted a gene encoding an approximately 28-kDa mature protein with a typical signal sequence. The adaA (acute disease antigen A) gene was detected in acute group C. burnetii isolates but not identified in chronic group isolates by PCR and Southern blotting. A typical signal peptide was predicted in adaA, and specific antibody to adaA reacted with the purified membrane fraction of acute group isolates by Western blotting, suggesting that adaA is exposed on the outer surface of C. burnetii. adaA was overexpressed in pET23a as a fusion protein in Escherichia coli to develop anti-recombinant adaA (anti-radaA) specific antibody, which recognized a approximately 28-kDa band in acute group isolates but not in chronic group isolates. In addition, immunoblotting indicates that radaA reacted with sera derived from animals infected with acute group isolates but did not react with sera from animals infected with chronic group isolates. These results support the idea that an adaA gene-targeted PCR assay and an radaA antigen-based serodiagnostic test may be useful for differential diagnosis of acute and chronic Q fever.

Acute Disease↗

PubMed2000

Detection of Coxiella burnetii DNA in dental pulp during experimental bacteremia.

Colonization of dental pulp by blood-borne bacteria in the absence of previous inflammation has been hypothetized but has never been convincingly demonstrated. In order to provide convincing support for this hypothesis we attempted to detect Coxiella burnetii DNA in the dental pulp of bacteremic, intraperitoneally inoculated guinea-pigs by PCR amplification and direct sequencing of two molecular targets. Coxiella burnetii DNA was recovered from 20-50% of the animals depending on the molecular target, from 15-20 days after experimental challenge. These results demonstrated, for the first time, that dental pulp is contaminated by blood-borne bacteria and can be detected by molecular tools.

Animals↗

PubMed1993

In vitro activities of ceftriaxone and fusidic acid against 13 isolates of Coxiella burnetii, determined using the shell vial assay.

The susceptibilities of 13 isolates of Coxiella burnetii to fusidic acid and ceftriaxone were determined by use of the recently described shell vial assay (D. Raoult, H. Torres, and M. Drancourt, Antimicrob. Agents Chemother, 35:2070-2077, 1991). At a concentration of 4 micrograms/ml, ceftriaxone was bacteriostatic for four isolates and slowed the multiplication of the other nine. Fusidic acid at a concentration of 2 micrograms/ml was bacteriostatic for six isolates and slowed the multiplication of three others. These results show that these compounds could be effective in the phagolysosome of C. burnetii-infected cells.

Ceftriaxone↗

PubMed1995

Conventional viral cultures and shell vial assay for diagnosis of apparently culture-negative Coxiella burnetii endocarditis.

A patient with culture-negative endocarditis was diagnosed with Q fever endocarditis based on the results of serological tests and positive leukocyte cultures obtained using conventional viral cultures and the shell vial technique. This case report suggests that isolation of Coxiella burnetii from blood may allow better diagnostic and therapeutical evaluation of patients with Q fever endocarditis. The use of both conventional and shell vial viral cultures is recommended for the isolation of Coxiella burnetii from the blood of patients with apparently culture-negative endocarditis.

Adult↗

PubMed1992

[Dependence between penetration route and course of infection with Coxiella burnetii in mice].

This study was aimed at investigation of course of Coxiella burnetii infection in mice infected by these bacteria by different routes. The animals infected intranasally, perorally, intraperitoneally and intravaginally by suspension of C. burnetii cells. Mice were also infected via peritoneal and intravaginal route with spermatozoa derived from infected males. In all animals at the same time specific antibodies against phase I and phase II antigens of C. burnetii belonging to IgG and IgM classes of similar titers appeared and this was detected by dot-blot immunoenzymatic test. Independently of route of infection C. burnetii were present in the liver, spleen, testicles, prostate and spermatozoa of tested animals. The bacteria were detected in these organs for 18 days of infection, in the blood for 7 days only, whereas in urine they appeared as late as 14 days after infection. The course of infection with C. burnetii in mice in thus similar regardless of site of bacterial penetration. Infection with C. burnetii may be also transmitted by a sexual route from male to female animals. Infection of female mice occurs both after intravaginal application of live suspension of C. burnetii or spermatozoa derived from infected males.

Animals↗

PubMed2005

Genome analysis of Coxiella burnetii species: insights into pathogenesis and evolution and implications for biodefense.

Coxiella burnetii, the etiological agent of Q fever, is a class B biodefense agent. We are continuing the momentum of discovery generated by the first Coxiella genome sequences by extending the breadth of genomics to include four additional heterogeneous C. burnetii strains. We are also sequencing the genome of Rickettsiella grylli, an intracellular parasite of grasshoppers and the closest known phylogenetic relative to the Coxiella group. These data will enable the investigation of fundamental questions about Coxiella pathogenicity and virulence as well as broader evolutionary questions about the transition to obligate intracellular life. Specifically, sequence comparisons will permit examination of genetic differences, allowing us to address key questions: What core genes are necessary for an obligate intracellular lifestyle and developmental cycle of the genus? What specific genetic determinants can be linked to virulence properties such as host preference, disease severity, and pathology (i.e., acute vs. chronic disease)? What are the frequencies of mutation and intragenomic recombination, and levels of genome reduction? What specific factors are relevant to colonization and virulence in human hosts (based on comparisons with R. grylli)? From a public health and biodefense perspective, exposure to different strains, either natural or due to illegitimate release, may have different outcomes. With extensive genomic-level information from diverse strains, investigators can determine effective drug and vaccine targets and design methods to accurately type Coxiella based on a subset of genes, opening the way for cost-effective targeted PCR- or antibody-based tests.

Biological Warfare↗

PubMed1991

Sequence and linkage analysis of the Coxiella burnetii citrate synthase-encoding gene.

The nucleotide (nt) sequence of the Coxiella burnetii citrate synthase-encoding gene (gltA), previously cloned in Escherichia coli, was determined. The nt sequence analysis revealed an open reading frame (ORF) of 1290 bp capable of coding for a protein of 430 amino acids (aa) with a deduced Mr of 48,633. Preceding an ATG start codon, a possible transcription start point (tsp) with homology to the E. coli promoter consensus was detected. A poly-purine-rich region occurred immediately upstream from the gltA reading frame and potentially serves as a ribosome-binding site. Additionally, a G + C-rich region of dyad symmetry 3' to the translational stop codon was found that could possibly function as a Rho-independent transcriptional termination signal. A large, nearly perfect, inverted repeat was identified upstream from the gltA tsp and was shown by Southern analysis to be present in multiple copies in the C. burnetii genome. The deduced aa sequence of C. burnetii GltA was optimally aligned with enzymes from various prokaryotic sources and one eukaryotic source (pig heart). Using perfect aa identity, the C. burnetii enzyme demonstrated the greatest homology with GltA from Acinetobacter anitratum (65%). Although only 26% aa identity was seen with the pig heart enzyme, many of the residues identified in ligand binding appear to be conserved. Sequencing studies of a region centered approx. 5.6 kb upstream from gltA revealed an ORF read with opposite polarity that encodes a peptide highly homologous to the C terminus of the flavoprotein subunit of E. coli succinate dehydrogenase. This report represents the first nt sequence analysis of a gene of known function from the obligate intracellular parasite, C. burnetii.

Amino Acid Sequence↗

PubMed1998

[Recurrent osteitis and Coxiella burnetii: the relation to chronic recurrent multifocal osteomyelitis].

UNLABELLED: Chronic recurrent multifocal osteomyelitis (CRMO) is a disorder of suspected--but unproved-infectious etiology. OBSERVATION: A girl presented with a typical CRMO involving successively the left fibula, radius, humerus and the right carpus. A Coxiella burnetii infection was indicated during the first attack. Two recurrences occurred in spite of suitable antibiotic treatment and with negative infectious investigation. Two months after stopping antibiotic treatment, a new recurrence associated with antibodies increase and positive bone culture occurred. CONCLUSION: Coxiella burnetii can initiate a CRMO. The mechanism involved is probably a delayed hypersensitivity. CRMO would therefore be the first type of reactive osteitis.

Anti-Bacterial Agents↗

PubMed1995

A new plasmid (QpDV) common to Coxiella burnetii isolates associated with acute and chronic Q fever.

Genetic studies of Coxiella burnetii strains suggested the possibility of differentiating new isolates according to their plasmid DNA content. Virulence and/or clinical manifestations ('chronic' and 'acute' Q fever) had been claimed to correlate with this plasmid typing. A new plasmid, named QpDV, was found to be common to C. burnetii isolates obtained from acute and chronic Q fever. According to the results obtained, plasmid usage for detection and differentiation of respective pathovars of C. burnetii and the correlation between gene specificity and pathovar has to be revised. Closer studies suggested a common origin of C. burnetii plasmids, but also showed some differences characteristic for each plasmid, probably reflecting divergent evolution.

Acute Disease↗

PubMed2002

Seroprevalence of Coxiella burnetii in selected populations of domestic ruminants in Newfoundland.

The seroprevalence of Coxiella burnetii among cattle, sheep, and goats in Newfoundland was determined by microimmunofluorescence. Seropositivity to phase II antigen increased in sheep from 3.1% in 1997 to 23.5% in 1999-2000 (P < 0.001). Cows (24%) had antibodies to phase I antigen; goats (15.6%) had antibodies to phase II antigen. Seroprevalence of C. burnetii is increasing among sheep.

Animals↗

PubMed1999

Acute cerebellitis caused by Coxiella burnetii.

We report a childhood case of severe acute cerebellitis caused by Coxiella burnetii. After 10 days of fever and headache, the patient fell into a drowsy state. Examination of the cerebrospinal fluid (CSF) revealed pleocytosis, an increased level of protein, and negative results in bacterial and viral studies. Magnetic resonance imaging demonstrated a herniated tonsil compressed by the swollen vermis. Administration of minocycline relieved the patient's clinical symptoms. C. burnetii was isolated from the CSF obtained during convalescence.

Acute Disease↗

PubMed1990

Coxiella burnetii antigens may induce resistance to tumour growth.

Coxiella burnetii antigens stimulate the defence against growth of hepatoma 22a cells. The antigen-stimulated mice survived longer, they considerably later developed palpable tumours and showed a retarded tumour growth. The enhanced resistance to tumour growth may be explained by at least 2 interrelated phenomena; namely by the induction of interferon-like activity and an increased NK cell activity.

Adjuvants, Immunologic↗

PubMed1967

Physiology of rickettsiae. VI. Host-independent synthesis of polyribonucleotides by Coxiella burnetii.

Preparations of purified and disrupted suspensions of Coxiella burnetii are able to incorporate ribonucleotides into polymers in the presence of adenosine, guanosine, cytidine, and uridine triphosphates. Nucleotide incorporation requires the presence of all four ribonucleoside triphosphates. The reaction is enhanced by the addition of phosphoenolpyruvate and pyruvic kinase, and exogenous deoxyribonucleic acid, and is inhibited by deoxyribonuclease and actinomycin D. Incorporation is maximal between pH 7.0 and 8.0, and at 37 C. The synthesized polymer is relatively insensitive to deoxyribonuclease and is sensitive to ribonuclease and dilute alkaline hydrolysis. The data indicate the presence of an autonomous deoxyribonucleic acid-dependent ribonucleic acid polymerase in the rickettsial agent.

Coxiella↗

PubMed1980

In vitro studies of interaction of rickettsia and macrophages: effect of ultraviolet light on Coxiella burnetii inactivation and macrophage enzymes.

The inactivation of Coxiella burnetii in suspension or in cultures of guinea pig peritoneal macrophages by ultraviolet (UV) light was studied. The effect of UV treatment on the activity of macrophage organelle marker enzymes and their subsequent equilibration in linear sucrose gradients was also determined. It was shown that UV treatment of 600 mu W/cm2 for 15 s at a distance of 10 cm inactivated C. burnetti, either in suspension (10(8) organisms per ml) or within guinea pig peritoneal macrophages. Similar UV treatment had little effect on the activity or equilibration of macrophage organelle marker enzymes in linear sucrose gradients. However, longer exposure caused considerable inactivation of these enzymes.

Acetylglucosaminidase↗