Bacterial protein mimics its host to disable a key enzyme
NEW YORK Helicobacter pylori, an infection that causes gastric ulcers and cancers of the gut, may be influenced by a bacterial protein that influences the structure of stomach tissue, scientists found.
C. Erec Stebbins, head of the Laboratory of Structural Microbiology at Rockefeller University, Research Associate Dragana Nesic and colleagues deciphered the atomic structure of an important segment of the large H. pylori protein CagA as it attached to a human enzyme called MARK2. MARK2 (also known as PAR1b) regulates processes, including the “tight junctions” that form between cells, packing stomach tissue together.
The researchers concluded that the protein’s make-up was similar to a human protein, but instead, it disrupted different cell functions. By injecting a protein into the stomach lining that mimics a native protein but has its opposite effect, the bacterium shuts down a process that aids the development of the stomach lining, scientists said.
H. pylori is known for its direct involvement in gastric ulcers and tumors, and the activity of the enzyme that CagA effectively shuts down has been implicated in other disorders, including Alzheimer’s disease and obesity. Understanding more about how CagA works is potentially useful for treating a litany of medical problems, researchers noted.
“Evolution has created a bacterial protein — CagA — that looks exactly like one of ours, and the enzyme that interacts with it is totally fooled,” Stebbins said. “CagA binds to it so tightly that the enzyme gets locked in this trapped, dead state and is unable to do what it usually would.
“What we hope is that now we’ve opened up CagA by showing how we can take this huge protein on,” Stebbins added. “We would love to see this kind of research accelerate because there is a lot more we need to understand about how it works.”
Tylenol Arthritis caplet recall becomes a bigger headache
NEW YORK Johnson & Johnson has expanded its voluntary recall of Tylenol Arthritis caplets in the wake of consumer reports of a moldy smell that can cause nausea and sickness. The recall now includes all product lots of the Arthritis Pain caplet 100-count bottles with the red EZ-Open cap.
Prior to this, the company had recalled five lots of the product in November, citing similar reasons, with user complaints of nausea, stomach pain, vomiting and diarrhea.
According to J&J, the odor is coming from trace amounts of 2,4,6-tribromoanisole — a chemical used to treat wooden pallets that transport and store packaging materials — which is believed to be the result from the breakdown of another chemical used in the manufacture of the drug.
To date, the side effects have been “temporary and non-serious,” although the health effects of the compound have not been studied.
The recall only affects the specific lots reported, and does not extend to any other Tylenol pain products.
J&J is moving its production of Tylenol Arthritis Pain caplets 100-count to another plant, and plans to reintroduce the product in January.
J&J is advising consumers seeking a refund or replacement to call (888) 222-6036.
P&G adds new products to Vicks DayQuil line
CINCINNATI Procter & Gamble on Wedneday introduced Vicks DayQuil Mucus Control and DayQuil Mucus Control DM. These products, which work for four hours, help loosen and thin mucus.
Vicks DayQuil Mucus Control provides mucus relief, making coughs more productive. In addition, DayQuil Mucus Control DM contains a cough suppressant for combined comfort of thinning mucus and controlling cough.
“When you are sick, your body produces excess mucus, which also becomes thicker and more difficult to clear,” stated Matt Kemme, brand manager, Vicks. “We’ve uncovered an insight that some consumers are restricting their mucus treatment to avoid coughing up phlegm in public,” he said. “The expectorant agent in Vicks DayQuil Mucus Control acts for four hours, helping people control over when and where they expel their mucus out.”
Average retail price ranges between $6.49 and $7.29.