Bacteria across our planet contain nanometer-sized factories that do many different things. Some make nutrients, others isolate toxic materials that could harm the bacteria. We have barely scratched the surface of their functional diversity.
But all share a common exterior, a shell made of protein tiles, that Michigan State University researchers are learning how to manipulate in the lab. This will allow them to build factories of their own design, using the natural building blocks. Indeed, scientists see the structures as a source of new technologies. They are trying to repurpose them to do things they don’t in nature.
In a new study, the lab of Cheryl Kerfeld reports a new genetically engineered shell, based on natural structures and the principles of protein evolution. The new shell is simpler, made of only a single designed protein. It will be easier to work with and, perhaps, even evolve in the lab. The study is published in ACS Synthetic Biology.
Natural shells are made of up to three types of proteins. The most abundant is called BMC-H. Six BMC-H proteins come together to form a hexagon shape to tile the wall.
At some time in evolutionary history, some pairs of BMC-H proteins became joined together, in tandem. Three of these mergers, called BMC-T, join to also form a hexagon shape.
“The two halves of a BMC-T protein can evolve separately while staying next to each other, because they are fused together,” said Bryan Ferlez, a postdoc in the Kerfeld lab. “This evolution allows for diversity in the structures and functions of BMC-T shell proteins, something that we want to recreate by design in the lab.”
To take his fledgling lab to new heights, Liangfang Zhang hatched a plan that he considered brilliant in its simplicity. It involved procedures that many of his peers found a little out there. But if he could make his idea work, it would clear a major hurdle to safely ferry therapies through the body on nanoparticles one-thousandth the width of a human hair.
Yet back in 2010, the young nanoengineer could not convince the National Institutes of Health, the main funder of U.S. biomedical research, to support the project. Zhang applied for funding four or five times over several years, to no avail.
“It felt quite lonely,” he says. “But I just felt this is very unique stuff. And it may become a big thing.”
Pulling funds from other projects and from the start-up package he received to set up his lab at the University of California, San Diego, Zhang did the experiments for his breakthrough paper, published in 2011 in the Proceedings of the National Academy of Sciences. He and coworkers created a new class of nanoparticles, made from carbon-containing polymers, that could slip through blood vessels in a mouse without triggering an immune reaction. While immune responses are important for killing disease-causing pathogens, the same reactions are a nuisance when they clear out molecules made to deliver lifesaving drugs.
Then, instead of just viewing their particles as a drug-delivery system, which most other researchers were focused on, Zhang and his team made a surprising pivot. They repurposed the particles to act as “nanosponges” that trap and remove toxins from the blood. In lab experiments, the nanosponges worked against toxins unleashed by E. coli and some of the harder-to-fight bacteria. Nanosponges also slowed harmful inflammation in mice with a form of rheumatoid arthritis and diverted HIV and Zika from the cells those viruses normally infect, the researchers reported last year.
Image Credit: MSU
News This Week
By early 2020, concern was mounting about a new, deadly coronavirus first detected in Wuhan, China. The World Health Organization had declared the coronavirus outbreak a global health emergency just days before. There had been [...]
As a COVID-19 and medical device researcher, I understand the importance of face masks to prevent the spread of the coronavirus. So I am intrigued that some mask manufacturers have begun adding graphene coatings [...]
Swansea University scientists have uncovered potentially dangerous chemical pollutants that are released from disposable face masks when submerged in water. The research reveals high levels of pollutants, including lead, antimony, and copper, within the [...]
Bowel cancer survival rates could be improved if chemotherapy drugs were delivered via tiny nanoparticles to the diseased organs rather than oral treatment. That's the finding from Indian and Australian scientists who have undertaken [...]
Pfizer CEO Albert Bourla says his company’s experimental COVID-19 treatment, a pill that can be taken at the first sign of the illness, could be available before the end of the year. Speaking on CNBC, Bourla said clinical [...]
At the University of Chicago, scientists have developed an absolutely innovative, promising treatment for COVID-19 in the form of nanoparticles with the ability to trap SARS-CoV-2 viruses inside the body and use the body’s [...]
Australian researchers have identified neutralizing nanobodies that block the SARS-CoV-2 virus from entering cells in preclinical models. The discovery paves the way for further investigations into nanobody-based treatments for COVID-19. Published in PNAS, the research [...]
Someday, scientists believe, tiny DNA-based robots and other nanodevices will deliver medicine inside our bodies, detect the presence of deadly pathogens, and help manufacture increasingly smaller electronics. Researchers took a big step toward that [...]
Experts have discovered what they believe is the world’s most mutated COVID strain – and there’s one detail in particular that has scientists worried. Scientists have detected what is believed to be the world’s [...]
SARS-CoV-2, the virus that causes COVID-19, likely does not directly infect the brain but can still inflict significant neurological damage, according to a new study from neuropathologists, neurologists, and neuroradiologists at Columbia University Vagelos [...]
ANSTO has contributed to a comprehensive investigation of a promising type of nanoparticle that could potentially be used for intractable brain cancers in a combined therapy. The study, which was led by Dr. Moeava [...]
The immune response needed to protect people against reinfection with the coronavirus will be explored in a new human challenge trial, researchers have revealed. Human challenge trials involve deliberately exposing healthy people to a [...]
Researchers from Duke University are developing a flu shot with the new technology that was used for two coronavirus vaccines. Both the Pfizer-BioNTech and the Moderna shots use part of the virus's genetic code [...]
Researchers from the University of Liverpool have shown the potential of repurposing an existing and cheap drug into a long-acting injectable therapy that could be used to treat Covid-19. In a paper published in the journal Nanoscale, [...]
Researchers have developed a new superbug-destroying coating that could be used on wound dressings and implants to prevent and treat potentially deadly bacterial and fungal infections. The material is one of the thinnest antimicrobial [...]