|
 |
|
| |
News
Items in Dailies |
| Microbe
hunters (The Hindu, March 20, 2003) |
The primary role of
the Defence Research and Development Establishment (DRDE),
Gwalior, Madhya Pradesh, is to provide research and
development systems to the Indian armed forces as they
increasingly contend with the new realities of biological
and other weapons of mass destruction. DRDE Scientists
have developed a diagnostic kit that uses the dot-ELISA
method to definitely identify the `leptospira' within
a couple of hours rather than days. Recently, they have
developed a system that can provide a confirmed diagnosis
of the `anthracis' toxin in a human within 2 hours.
The DRDE has also released recently a quick and accurate
test kit for typhoid that costs less than Rs. 10 per
test, and provides a result in minutes. |
| Cheap
vaccines from bacterial viruses (The Hindu, March 20,
2003) |
Genetically altered
bacterial viruses appear to be more effective than naked
DNA in eliciting an immune response and could be a new
strategy for a next generation of vaccines that are
easy to produce and store, say researchers from Moredun
Research Institute in Britain. "In theory, millions
of doses can be grown within a few days using simple
equipment, media and procedure," says John March,
a lead researcher presenting findings at the American
Society for Microbiology's Biodefense Research Meeting.
Bacteriophages are viruses that infect bacteria but
not humans. In this, March and his colleagues used a
bacteriophage as a vehicle for the genes from the hepatitis
B virus in mice and compared its ability to elicit a
protective immune response with a vaccine made of the
naked DNA.
They found that the bacteriophage could induce an immune
response and the number of bacteriophage they needed
was less than one per cent of the number of pieces of
naked DNA required to mount an effective immune response.
Using bacteriophages to deliver vaccine components gives
many advantages over vaccination with naked DNA, says
March. The DNA is protected inside the protein shell
of the virus making it longr lasting and easier to store.
In addition, bacteriophages have a large cloning capacity,
making large-scale production cheap, easy and extremely
rapid.
|
| Relationships
between humans, microorganisms (The Hindu, April 03, 2003) |
|
Researchers
at Washington University School of Medicine in St. Louis
have completed sequencing the genome of Bacteroides
thetaiotaomicron, one of the most prevalent bacteria
that live in the human intestine. The results appeared
in Science "Humans enjoy mutually beneficial relationships
with billions of bacteria that live in our gut. Discovering
how these microbes manipulate our biology to benefit
themselves and us should provide new therapeutic strategies
for preventing or treating various diseases," says
principal investigator Jeffrey I. Gordon.
According to Gordon the human body
is home to diverse communities of microorganisms. It
is estimated that adults are composed of 10 times more
microbial cells than human cells. The intestine harbours
our largest collection of microbes. It appears that
the gut contains at least 1,000 different species of
bacteria, and that their collective genomes ('the microbiome')
contains 100-fold more genes than the human genome.
These bacteria provide certain metabolic capabilities
that humans lack, including the ability to process nutrients
that human genes cannot break down.
Gordon's team analyzed the bacteria
as a representative of this microbial community. "This
bacterium becomes prominent beginning at a key developmental
transition that takes place when infants are weaned
from their mother's milk and begin eating a diet rich
in polysaccharides," Gordon says.
By decoding the bacterium's genome,
he identified some of the strategies it employs to forge
a beneficial alliance with its host. For example, over
100 of its 4,800 genes appear to be dedicated to retrieving
dietary polysaccharides from the intestinal cavity.
The team also discovered that the bacteria contain an
elaborate and novel apparatus for sensing its environment
so that the correct combination of enzymes that grab
and degrade carbohydrates can be expressed when nutrients
are available. Also, the organism has a rich repository
of genes that allow it to manufacture carbohydrates
on its own cell surface.
By changing the features of this carbohydrate
mask, the organism may be able to camouflage itself
from the host's immune system. The bacterium also appears
to be well equipped to refashion its own genome over
time. This capacity may be the key to understanding
the evolutionary processes that sustain beneficial symbiotic
relationships between number of bacteria and their hosts.
The gut microbiome not only has the potential to help
us more fully define the complete complement of genes
associated with our bodies, but it also represents a
fertile field to prospect for natural products that
may become tomorrow's wonder drugs." |
| Magnetic
bugs cut sewage sludge (Indian Environment online) |
Magnetic bacteria
could cut sewage sludge. They could shave up to five
tones of waste off the several hundred tones produced
every day by a plant serving 100,000 people, say Japanese
researchers Bacteria used to break down some harmful
pollutants in wastewater add to leftover sludge. Much
of this ends up buried in landfills. But microbes will
cling to powdered iron sprinkled into the brew, find
Yasuzo Sakai, of Utsunomiya University, and his colleagues.
Magnets can then drag them out, reducing the sludge
volume and enabling a plant to re-use the bugs. A year-long
test, in which 80 liters of raw sewage were passed through
a rotating magnetic drum every day, produced no bacterial
sludge, Sakai told this week's meeting of the American
Chemical Society in New Orleans. "Magnetic separation
is fast and reliable," he says. Further, the researchers
have now teamed up with water-treatment companies and
local government to build a pilot plant that will treat
30 tones of sewage per day. |
|
|
|
|
|
|
