5 Rise in the
temperature over the past
century. It is currently
projected that the average
temperature will rise 0.5–
8. 6 °F over the next 100 years.
Rate of occurrence
per cell per day of
oxidative DNA damage
in humans. The 2015
Nobel Prize in Chemistry
scientists who mapped
DNA repair systems at a
1. 9 x 1019
Half-life in years of
alpha decay, which is longer
than the estimated age of
Nicotine-eating bacteria could one
(equal to 6. 7 in)
the global sea level rose in
the past 100 years.
day help smokers kick the habit
Most people who smoke cigarettes know it’s bad for their health, but quitting
is notoriously difficult. To make it easier, researchers are turning to bacteria
that thrive on nicotine, the addictive component in tobacco. In the Journal
of the American Chemical Society, they report successful tests on a bacterial
enzyme that breaks down nicotine and could potentially dull its effects in
Tobacco use remains the leading cause of preventable disease, disability, and death in the United States.
Smokers who want to quit can turn to various pharmacological aids. These include patches, gum, and other
nicotine-releasing products designed to replace cigarettes, as well as drugs that sequester nicotine in the body
to prevent it from reaching the brain, where its addictiveness takes hold.
But the success rates of these options are low. Only about 15–30%
of smokers who try them are able to stop smoking for longer
than one year. Kim D. Janda and colleagues wanted to try
a new angle.
Janda and his research team used an enzyme
called NicA2 that comes from Pseudomonas putida,
a kind of bacteria already known to degrade tobacco
waste. In lab tests, NicA2 broke down all the nicotine
in blood samples within 30 minutes. It also remained
stable for more than three weeks in a buffer solution and at least three days in serum, and mice
given the enzyme showed no observable side effects.
Read more about the research: “A New Strategy
for Smoking Cessation: Characterization of a Bacterial
Enzyme for the Degradation of Nicotine,” Journal of the
American Chemical Society, 2015, 137 (32), pp 10136–10139.
Portable device can quickly
test for sickness-causing
toxins in shellfish
Mussels, oysters, scallops, and clams might be
ingredients for fine cuisine, but they can also be a
recipe for diarrhetic shellfish poisoning (DSP). That’s
a gastrointestinal illness people can get if those
tasty morsels contain marine toxins. Now, researchers are reporting in ACS’s Journal of Agricultural
and Food Chemistry the development of a portable,
inexpensive device that can quickly and easily screen freshly caught
shellfish for these
DSP is caused by eating
shellfish that have accumulated okadaic acid (OA)
or related marine toxins.
Algal blooms — commonly
referred to as “red tides” —
can produce these substances,
which shellfish can accumulate through filter feeding. Because cooking
the shellfish does not destroy the toxins, several regulations are in place
to prevent the sale and consumption of tainted shellfish. To comply with
these regulations, the current practice is to send samples to labs that
use expensive, slow, and technically intense tests. Waqass Jawaid and
colleagues set out to develop an inexpensive, easy-to-use, and portable
device that could quickly test shellfish on boats and other remote loca-
tions but could also maintain the rigorous testing standards of off-site
labs. The researchers adapted a test called a lateral flow immunoassay
(LFIA), which is like a home pregnancy test strip. This LFIA combines
simple test procedures with an antibody previously shown to specifi-
cally bind to three OA toxins. The small, portable device can accurately
screen for the presence of these substances in less than 20 minutes on
a boat, before they go further into the supply chain. If the test is posi-
tive, then the shellfish would not be sold. If the LFIA readout is negative,
then an additional, easy-to-use test could be conducted dockside for
“total toxins”, which would include detection of a fourth
type of OA.
The authors acknowledge funding from Innovate UK,
Scottish Enterprise, and Neogen Europe Limited.
Read more about the research: “Development
and Validation of a Lateral Flow Immunoassay
for the Rapid Screening of Okadaic Acid and
All Dinophysis Toxins from Shellfish Extracts,”
Journal of Agricultural and Food Chemistry,
2015, 63 (38), pp 8574–8583.