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Researchers at UC San Diego who last year genetically engineered bacteria to keep track of time by turning on and off fluorescent proteins within their cells have taken another step toward the construction of a programmable genetic sensor. The scientists recently synchronized these bacterial “genetic clocks” to blink in unison and engineered the bacterial genes to alter their blinking rates when environmental conditions change.

Their latest achievement, detailed in a paper published in the January 21 issue of the journal Nature, is a crucial step in creating genetic sensors that might one day provide humans with advance information about temperature, poisons and other potential hazards in the environment by monitoring changes in the bacterium’s blinking rates.

“Programming living cells is one defining goal of the new field of synthetic biology,” said Jeff Hasty, associate professor of biology and bioengineering at UCSD who headed the research team with Lev Tsimring, associate director of UCSD’s BioCircuits Institute.
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A new fast-acting disinfectant that is effective against bacteria, viruses and other germs could help stop the spread of deadly infections in hospitals, German scientists said on Wednesday.
Researchers from the Robert Koch Institute in Berlin said they had developed a fast-acting, practical formula which would kill germs on surgical instruments without damaging them through corrosion.

Disinfectants are the first line of defense against the spread of hospital-acquired infections and effective cleaning of surgical instruments is vital to beating them.

The German formula works against a wide range of germs, including some that survive ordinary disinfectants, such as Mycobacterium avium bacteria which can cause a tuberculosis-type illness and enteroviruses that may cause polio.

Drug-resistant bacteria, the so-called “superbugs,” are a growing problem in hospitals worldwide and poor hygiene among staff is often blamed for the spread of such infections. They kill about 25,000 people a year in Europe and about 19,000 in the United States.

In previous studies, the German team found a simple alkaline detergent that could eradicate prions — disease-causing proteins that are particularly hard to get rid of because they can become fixed onto surfaces through the use of some conventional disinfectants.

In their new study, Michael Beekes and Martin Mielke from the Institute’s hygiene department mixed the alkaline with varying amounts of alcohol and tested its ability to rid surgical instruments of bacteria, viruses and fungi and prions. They found that a mixture with 20 percent alcohol was best.

Beekes said he thought the new disinfectant could have a huge impact on hospital safety protocols.

“Standard formulations that eliminate prions are very corrosive,” he said in the study published in the Journal of General Virology.

“The solution we’ve come up with is not only safer and more material-friendly, but easy to prepare, cheap and highly effective against a wide variety of infectious agents.”

A Dutch study published last week found that the methicillin-resistant staphylococcus aureus (MRSA) superbug, which can cause blood poisoning, spreads not freely but in clusters, suggesting it is spread through healthcare systems by patients being repeatedly admitted to different hospitals.

Bacteria can swim, propelling themselves through fluids using a whip-like extension called a flaggella. They can also walk, strolling along solid surfaces using little fibrous legs called pili. It is this motility that enable some pathogenic bacteria to establish the infections such as meningitis that cause their human hosts to get sick or even die.
Now researchers at the University of North Carolina at Chapel Hill have discovered that a single atom — a calcium, in fact can control how bacteria walk. By resolving the structure of a protein involved in the movement of the opportunitistic human pathogen Pseudomonas aeruginosa, the scientists identified a spot on the bacteria, that when blocked, can stop it in its tracks. The finding identifies a key step in the process by which bacteria infect their hosts, and could one day lead to new drug targets to prevent infection.
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