NOV 15, 2015 6:16 PM PST

Sequencing Irradiated Anthrax

WRITTEN BY: Kerry Evans
It’s now possible to sequence DNA from samples of irradiated bacteria, making it simpler and safer to identify potential bio-terror agents.

The CDC defines bioterrorism as “the deliberate release of viruses, bacteria, or other germs (agents) used to cause illness or death in people, animals, or plants”.  Likely one of the most well-known bioterror agents is Bacillus anthracis, the causative agent of anthrax.
 
Anthrax is considered a bioterror agent.

B. anthracis is a Gram-positive rod that lives in the soil.  Bacillus species form spores that can remain viable for decades and are easily aerosolized as bioterror agents.  B. anthracis also produces a capsule and toxin that contribute to its virulence.  The capsule protects the bacteria from complement and phagocytosis, while the toxin kills immune cells.  

While it usually only causes disease in cattle, B. anthracis readily infects humans when given the chance. Cutaneous anthrax results when bacteria or spores enter through a cut in the skin, resulting in necrotic ulcers and septicemia.  Inhalation anthrax, commonly associated with bioterrorism, causes acute chest pain and fever, followed by systemic hemorrhaging.  

To minimize the risk of a bioterror attack, mail sent to certain government officials is irradiated to kill anthrax spores and other agents.  The problem is that irradiation fragments DNA, making it difficult to sequence and identify a bioterror agent.  However, researchers at the US Army Edgewood Chemical Biological Center have optimized shotgun sequencing to piece together full sequences of DNA from irradiated bacteria.  

The group irradiated B. atrophaeus spore (a non-pathogenic relative of B. anthracis) along with cells of Yersinia pestis.  In each strain, the irradiated sequences matched controls, indicating that the group successfully sequenced and pieced together the irradiated DNA fragments.  

According to study author Henry Gibbons, "rapid sequencing of irradiated materials from a biocrime would allow quick characterization of the material".  Such information could help investigators track down those responsible for the crime.  

Sources: Science Daily, Applied and Environmental Microbiology, CDC, Textbook of Bacteriology, Wikipedia
About the Author
  • Kerry received a doctorate in microbiology from the University of Arkansas for Medical Sciences.
You May Also Like
JUN 13, 2020
Microbiology
New Spikes in COVID-19 Cases in Eight States and China
JUN 13, 2020
New Spikes in COVID-19 Cases in Eight States and China
COVID-19 cases have been rising in several states, and China has identified a new outbreak.
JUN 30, 2020
Plants & Animals
Consequences of Sixth Mass Extinction Threaten Humanity
JUN 30, 2020
Consequences of Sixth Mass Extinction Threaten Humanity
Many scientists have taken note of the rapid decline many of the world species, and several have declared that Earth's s ...
JUL 06, 2020
Microbiology
SARS-CoV-2 Makes Cells Sprout Infectious Tentacles
JUL 06, 2020
SARS-CoV-2 Makes Cells Sprout Infectious Tentacles
The pandemic coronavirus has caused a wide range of different symptoms, and as time goes on, we may find that it can hav ...
JUL 28, 2020
Microbiology
After 100 Million Years Under the Seafloor, Ancient Microbes Come Alive
JUL 28, 2020
After 100 Million Years Under the Seafloor, Ancient Microbes Come Alive
It has been said that we know more about the moon than we do about the bottom of the ocean, though explorers and researc ...
AUG 02, 2020
Microbiology
Examining the Existence of Organelles in Bacteria
AUG 02, 2020
Examining the Existence of Organelles in Bacteria
Cells can be grouped into two general categories: prokaryotic, which make up microbes like bacteria and archaea, or euka ...
AUG 11, 2020
Cell & Molecular Biology
New Microscopy Tools Reveal More About the Role of Actin
AUG 11, 2020
New Microscopy Tools Reveal More About the Role of Actin
Cells rely on a network of tiny filaments to give them form and support their structure. One crucial filament is a prote ...
Loading Comments...