Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Q Fever microbe’s genome is deciphered

15.04.2003


Study sheds light on potential bioterror agent, Coxiella burnetii



Scientists at The Institute for Genomic Research (TIGR) and their collaborators have deciphered and analyzed the complete genome sequence of Coxiella burnetii, a potential bioterror agent that causes Q Fever.

C. burnetii, which was first isolated as the cause of Q Fever in Australia in 1937, is typically found in farm animals but also infects humans, including an epidemic that sickened many soldiers in Europe during World War II. Typically, Q Fever does not kill people, but causes fever and other flu-like symptoms.


Because C. burnetii is an obligate intracellular pathogen – unable to replicate unless it is inside the cells of another living organism -- it is difficult to study in laboratories. That makes the complete DNA sequence an extremely valuable resource for researchers.

“The genome sequence offers a treasure trove of information that will allow scientists to develop a much higher-resolution picture of Coxiella’s biology and its ability to cause disease,” says John F. Heidelberg, the TIGR scientist who supervised the project.

The paper will be published online this week by the Proceedings of the National Academy of Sciences (PNAS), and will appear in the journal’s April 29 issue. The sequencing project was supported by the Defense Advanced Research Projects Agency (DARPA) and the National Institute of Allergy and Infectious Diseases (NIAID).

The TIGR study found that the C. burnetii genome appears to be in the early stages of “reduction” – a process during which degraded or non-functional genes are slowly eliminated as the organism becomes more dependent on its host for nutrition. Even so, scientists say, the Q Fever microbe does not appear to be quite as dependent on its human or animal host as other intracellular pathogens that cause leprosy, chlamydia, typhus, and Legionnaire’s Disease.

“This may mean that Coxiella became an intracellular pathogen more recently than other, somewhat similar pathogens,” says Rekha Seshadri, the TIGR staff scientist who is the lead author of the PNAS paper. “Comparing Coxiella with the genomes of other intracellular pathogens reveals fundamental differences in the organization and evolution of their chromosomes, as well as in their strategies for surviving inside host cells.”

The analysis found numerous genes that appear to be involved in the pathogen’s virulence and interactions with its host. In addition, Seshadri says, researchers found that the C. burnetii genome – which includes multiple “mobile elements” of DNA – seems to be less stable than that of other obligate intracellular pathogens such as Rickettsia and Chlamydia. The evidence of mobile elements and gene degradation suggests greater genome flux.

The study was led by TIGR researchers in collaboration with other scientists, including James E. Samuel of the Department of Medical Microbiology and Immunology at Texas A&M University System Health Science Center, in College Station, TX; Herbert A. Thompson of the Centers for Disease Control and Prevention (CDC) in Atlanta, GA; and Robert A. Heinzen of the NIAID’s Rocky Mountain Laboratories in Hamilton, MT.

“The availability of the genome sequence for Coxiella burnetii will provide a quantum leap to the investigators engaged in understanding the biology of this pathogen,” said Samuel of Texas A&M. “The most immediate application of the genome sequence will be testing of the predicted essential genes for Coxiella’s survival.”

Samuel said the genome sequence – coupled with NIAID’s heightened emphasis on vaccine development for Q Fever and other Category B potential bioterror agents – is likely to accelerate the development of better vaccines and diagnostic tests using genomic and proteomic approaches.

The CDC’s Thompson, co-editor of the book Q Fever: The Biology of Coxiella burnetii, says, “Q Fever research on all fronts will benefit from this new knowledge.” Over the last several years, he says, “consideration for both the organism Coxiella and its disease manifestations have been neglected” – mainly because of the difficulties involved with studying and manipulating the organism in the lab. “Knowledge of the genome should significantly aid our inquiries and guide us as we attempt to remedy these shortcomings.”

Heinzen, of NIAID’s Rocky Mountain Laboratory, says that having Coxiella’s complete genome sequence “is a major advance that will allow scientists to more easily conduct functional studies of genes potentially involved in virulence.” He said the pathogen interests scientists because it has “an amazing ability to survive in the environment and to resist degradation by its macrophage host cell.”

TIGR, which in 1995 published the first complete genome sequence of a free-living organism, is a world leader in microbial genomics. The institute has completed the full sequences of about 50 organisms or microbial strains – including the potential bioterror agents Bacillus anthracis and Brucella suis – and is now working on numerous other sequencing projects.

C. burnetii is listed as a potential bioweapon/bioterror agent because it is highly infective, relatively stable, and because Q Fever’s flu-like disease symptoms make early diagnosis difficult. During the 1950s and 1960s, the U.S. military conducted research into the potential use of C. burnetii as a biowarfare agent. But that stockpile was destroyed after the U.S. government halted its biowarfare program in 1969. The former Soviet Union also conducted Q Fever bioweapons research during the Cold War.


The Institute for Genomic Research (TIGR), which sequenced the first complete genome of a free-living organism in 1995, is a not-for-profit research institute based in Rockville, Maryland. TIGR conducts research involving the structural, functional, and comparative analysis of genomes and gene products in viruses, bacteria, archaea, and eukaryotes.

Media Contacts:

John Heidelberg, TIGR Assistant Investigator, (301) 838-2528; jheidel@tigr.org

Rekha Seshadri, TIGR Staff Scientist, rekha@tigr.org

Robert Koenig, TIGR Public Affairs Manager, (301) 674-9223; rkoenig@tigr.org

John Heidelberg | EurekAlert!
Further information:
http://www.tigr.org/

More articles from Life Sciences:

nachricht Closing the carbon loop
08.12.2016 | University of Pittsburgh

nachricht Newly discovered bacteria-binding protein in the intestine
08.12.2016 | University of Gothenburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Closing the carbon loop

08.12.2016 | Life Sciences

Applicability of dynamic facilitation theory to binary hard disk systems

08.12.2016 | Physics and Astronomy

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D

08.12.2016 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>