Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Using the genomic shortcut to predict bacterial behavior

05.07.2005


How do you study a pathogen that can’t survive outside its host’s cells? In a new study published in the open access journal PLoS Biology, Hiroyuki Ogata and colleagues show that sequencing and analyzing the genome of the bacteria Rickettsia felis provide valuable insights into the biology and behavior of this intracellular pathogen. The researchers discovered that the parasitic bacterium has the standard large circular chromosome plus two unexpected plasmids, small circular pieces of DNA that can replicate on their own. This discovery may lead to novel techniques for study. "The newly identified plasmids may become a basis of a new tool, such as for efficiently producing rickettsial proteins," explains Ogata.


The common flea can carry Rickettsia felis bacteria in its cells



Other Rickettsia species include the pathogens responsible for typhus and Rocky Mountain spotted fever. "Up to now, due to the lack of appropriate genetic transformation tools for rickettsiae, detailed molecular studies were difficult for these bacteria," says Ogata. But with new tools and "because of the medical importance of this group of bacteria, different teams of researchers are sequencing the genomes of different species of Rickettsia felis. We determined the genome sequence of Rickettsia felis, which is the fourth Rickettsia genome completely determined." R. felis is the only species known to have a plasmid.

Ogata and colleagues also made surprising discoveries about sexual activity in these bacteria. The larger plasmid encoded proteins typically associated with bacterial sex, called conjugation. The researchers also observed pilli, the bacterial conjugation bridge. Previously, researchers believed that intracellular bacteria did not exchange genetic material with each other. But Ogata explains that the new findings "forced us to change this static view."


In addition to conjugation, the researchers found evidence of other mechanisms for the bacterium to reshuffle its DNA. The R. felis genome encodes a large number of transposases, enzymes that cut and paste chromosomal DNA, and bears traces of multiple types of mobile gene elements and acquisition of genes from other, non-rickettsial, bacteria.

The research demonstrates that genomic analysis can provide new information about an organism efficiently. "Our study demonstrates the importance of sequencing a bacterial genome, even if several closely related genomes have been already determined. It is very difficult to correctly forejudge the diversity of bacterial genomes," Ogata says. "Thus we have to sequence more."

Paul Ocampo | EurekAlert!
Further information:
http://www.plosbiology.org

More articles from Life Sciences:

nachricht Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover

nachricht First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>