Web application to help discover new antibiotics to fight gram negative bacteria

A new web app eNTRyway speeds the discovery of drugs to kill Gram-negative bacteria by quickly evaluating potential drugs ability to accumulate in these bacterial cell. Entryway calculates physiochemical properties of molecules and compares to a training set of compounds. The tool also offers insights into discrete chemical changes that can convert drugs that kill other bacteria into drugs to fight Gram-negative infections.

The team proved the system works by modifying a Gram-positive drug and testing it against three different Gram-negative bacterial culprits in mouse sepsis. The drug was successful against each.

The researchers report their findings in the journal Nature Microbiology.

Researchers have so far identified more than 60 antibiotics that are effective only against Gram-positive bacteria but can be converted into drugs to fight Gram-negative infections. These compounds kill bacteria in a variety of different ways. The newly created drug, known as Debio-1452-NH3, interferes with fatty acid synthesis in bacterial – but not mammalian – cells.

Bacteriophage treatment for alcohol related liver disease

Researchers from King’s College London and the University of California San Diego School of Medicine conducted an animal study in mice and shown promise of bacteriophage therapy in treating alcohol-related liver disease.

This research is published in journal Nature.

The team discovered that patients with severe alcoholic hepatitis had high numbers of a destructive gut bacterium Enterococcus faecalis, which produced a toxin called cytolysin. This toxin is shown to injure liver cells. Enterococcus faecalis is normally found in low numbers in the healthy human gut.

To investigate the potential for phage therapy, the researchers isolated four different phages that specifically target cytolysin-producing Enterococcus faecalis. When they treated the mice with these, the bacteria were eradicated, and alcohol-induced liver disease was abolished. Control phages that target other bacteria or non-cytolytic E. faecalis had no effect.

With the rise of multidrug-resistant infections, people are looking at alternatives to antibiotics. Bacteriophages are viruses that kill bacteria. These bacteriophages are naturally occurring and offer a promising alternative to antibiotics. However, much research is needed to establish their safety and efficacy in clinical practice. The current study show promise of using phage therapy to alter the gut microbiome in cases with alcoholic liver disease.

Researchers develop self sterilizing bacterial air filter using graphene

Rice University researchers have developed self-sterilizing bacterial air filters using graphene. Workings of this novel air filter are published in the American Chemical Society journal ACS Nano.

This devise captures bacteria, fungi, spores, prions, endotoxins and other biological contaminants carried by droplets, aerosols and particulate matter. The filter then prevents the microbes and other contaminants from proliferating by periodically heating up to 350 degrees Celsius (662 degrees Fahrenheit), enough to obliterate pathogens and their toxic byproducts.

The filter utilizes laser-induced graphene. ¬†This is a conductive foam of pure, atomically thin carbon sheets synthesized through heating the surface of a common polyimide sheet with an industrial laser cutter. The process discovered by Tour’s lab in 2014 has led to a range of applications for electronics, triboelectric nanogenerators, electrocatalysis, water filtration and even art.

The lab tested LIG filters with a commercial vacuum filtration system, pulling air through at a rate of 10 liters per minute for 90 hours, and found that Joule heating successfully sanitized the filters of all pathogens and byproducts. Incubating used filters for an additional 130 hours revealed no subsequent bacterial growth on the heated units, unlike control LIG filters that had not been heated.

This filter provides use case scenarios especially in hospitals, schools, and passenger aircraft. Although similar air filtration systems are available currently, self sterilization of filter holds promise as it can reduce number of filters used and their replacement frequency there by providing a cost reduction. However further research is required before this product is fully implemented.

MNO