Lab Technique Makes Bacteria Face the Music, and it is Metal!

Ever since I learned about the dangers of antibiotic drug resistance in high school biology, an occasional anxiety visits me and reminds me that the time bomb hasn't been diffused. The horror stories my wrestling coaches told me about MRSA to make sure we mopped the mats properly did little to help this. The tale goes that a patient with a bacterial infection chose to stop taking their antibiotics when they felt better, rather than when the doctor prescribed. As figure 1 explains, the population takes the opportunity to regenerate; not only will the infection return, but now with the ability to resist antibiotics on a larger scale. 

Fig. 1: Genetic adaptation and transference allow a population to survive antibiotics.

A rather ominously titled report by the CDC reports that on average, someone in the United States gets an antibiotic-resistant infection every 11 seconds and every 15 minutes someone dies. This statistic is lower than in previous years, but not without a warning: "Without continued vigilance, this progress may be challenged by the increasing burden of some infections." As we watch the United States cut funding from the World Health Organisation, and Capitalists steadily combat affordable healthcare, only the willfully ignorant could miss the writing on the wall. Antibacterial Resistance is going to become a major threat once again.

Purdue University engineers recently developed a laser-texturing technique that allows metal surfaces to kill bacteria instantaneously. The team already proved this technique effective against the MRSA I was so afraid of as a kid. This massive step toward reducing the spread of infectious bacteria creates nano-scale patterns on the metal's surface. The patterns increases surface area of the metal, allowing for contact with more bacteria. An article detailing the discovery emphasizes on the efficacy of this lab technique over various nano-coating techniques that attempted to enhance the antibacterial properties of metals in the past. Laser texturing adds no new substance, while the substances nano-coating used were often toxic. 

Fig 2: Laser Texturing. Increased surface area allows for the lethal dose of copper ions to enter bacteria much faster.

The continuing research of how to face upcoming health challenges is indispensable. If it is not impressive enough that the engineers at Purdue University amplified the disinfectant properties of metal to such a degree, than consider the secondary impact of the technique. As can be seen in the University's video, this technique makes metal surfaces more hydrophilic. Orthopedic implants will attach more strongly and safely, improving the integration of the implants into bone. 

Bacteria and Nanowires: A Match Made for Space

Nanowires

An article published on, sciencedaily.com, chemists at the University of California- Berkeley, may have found the means to sustain life on Mars and reduce the amount of carbon dioxide in the atmosphere. The rise of carbon dioxide due to the burning of fossil fuels and deforestation has been seen across the globe. With the rise in carbon dioxide in the atmosphere a multitude of results have been yielded. The greenhouse effect, when gases such as carbon dioxide trap the sun’s heat which causes a rise and temperature, but one of these results. The greenhouse effect coupled with deforestation and other forms of pollution are promoting climate change, which has had drastic effects on wildlife and the environment. 

 

Sporomusa ovata

Scientists have created a hybrid (biomechanical) system of bacteria and nanowires that uses solar energy to convert carbon dioxide and water into other organic molecules such as carbohydrates, oxygen, and acetate. The nanowires are thin silicon strands, about one hundred times thinner than a strand of human hair, which are used as the electrical components and solar cells. These scientists have also hit a new milestone and have begun packing bacteria (Sporomusa ovata) in the nanowires. The nanowires conduct the solar energy to the bacteria while the bacteria is able to pull carbon dioxide from the air, add some water and you have a process very similar to photosynthesis. 

At first the efficiency of this method was not the best but, that was soon corrected. The conservation of the solar energy to organic molecules was similar to the efficiency of photosynthesis in plant but drastically low when compared to silicon solar panels. They first tried to just add more bacteria but soon realized that the pH of the surrounding water used for the process increased, this caused the bacteria to separate from the wires and break the circuit. To fix this they found a way to keep the water slightly acidic in order to counteract the continuous acetate production. This also allowed them to pack more bacteria into the nanowires, increasing efficiency by a factor of almost 10, making this more efficient than photosynthesis conducted by most plants. 

With this system able to draw carbon dioxide from the air this could directly address climate change by helping to remove excess carbon dioxide. Scientists also believe that this system could be essential in helping support colonies on Mars. There is expected to be a vast amount of frozen water just beneath the surface of Mars. With this biohybrid system, Mars colonists would have the raw material needed in order to begin the first colonies. 

Who is qualified for Covid pass?

In a coronavirus outbreak piece in the New York times, reporter Jason Horowits discusses the circumstances of going back to work in Italy. In order for the Italians to go back to work they have to have the right antibodies. Since the curve of the new infected cases in Italy is going down, governors  along with researchers and scientists are determining the proper way of when and how to reopen without facing any new challenges.

 Italy has reported the highest coronavirus death toll of any country.Credit...Alessandro Grassani for The New York Times

A special license has been proposed for Italians who possess antibodies that show they have had beaten the virus. The process of giving these licenses is not clear yet. As the number of cases has been decreasing, the governors of Italy are thinking seriously about reopening the economy. Due to the fact that Italy was one of the first infected countries with very large numbers of infected and death cases, it gives the researchers the opportunity to gain insight into how the virus works and biological properties that protect against it.

The intensive care unit for critical coronavirus patients at the Papa Giovanni hospital in Bergamo, near Milan

Scientists in Italy have found out that the virus resulted in two types of antibodies, one that appears at the first week of the infection and the second one that appears after 20 days and as a result show that the person has had the virus. further studies are being processing for safely reopening in Italy.

The Science of Hugging: What we Lose when we are Isolated

In "Op-Art" piece in the New York Times, Kristen Radka, author and illustrator outlines the science behind our need to touch and what we lose when we isolate ourselves to prevent the proliferation of disease.  She recounts moving to a town where she knew no one and lived alone.  She found herself growing hungry for some kind of human touch.

Art from Kristen Radka's New York Times piece.

She notes the science behind our need for touch.  Regular touch release oxytocin and leads to feelings of compassion.  It reduces levels of stress hormones like cortisone, cortisol and dihydro-cortisone.

Stress homones include dihydro-cortisone

Regular hugs strengthens the immune system helping to fight infection and reducing the severity of febrile diseases like flu and covid 19.  It also lowers blood pressure, particularly important for expectant mothers.  It is all of this we lose when we isolate ourselves in response to a pandemic.

Money Doesn’t Grow on Trees, but Nickels Do

     The agriculture industry is now harvesting more than just food. Some plants can harvest metal, such as nickel, through a phenomenon known as phytomining. In a recent article from The New York Times, Ian Morse examines this agricultural phenomenon. The sap of these phytomining plants can be sliced open or put through a peanut press to harvest the one-quarter nickel sap. This nickel-producing sap is more concentrated than the 1.2% nickel ore produced from smelting.

     Plants phytomine by collecting minerals from the soil and storing them at high levels, known as hyperaccumulation. There are approximately 700 known plants that thrive in metal-rich soil, at least 65 of which can phytomine nickel. These plants have adapted to their metal-rich environments and they are thought to use the nickel to control pests or more easily gather potassium from the soil.

Fig 1: Testing paper turning a reddish color, indicating high nickel content.

     Dr. Alan Baker from the University of Melbourne has researched the relationship between plants and soil since the 1970s. To prove the efficiency of phytomining as a source of metal, he rented a small plot of land in Malaysia. Every six to twelve months, farmers harvested 1 foot of the plant growth and squeezed or burned the metal-containing sap out of the plants. The sap was then purified and collected. This small plot produced about 500 pounds of nickel citrate, worth thousands of dollars. Nickel is a crucial component used in stainless steel, batteries for electric vehicles, and renewable energies.

     Baker and his colleagues are now scaling up to a 50 acre plot of land with the hopes of combating the mining industry. Mining industries have become increasingly controversial in the age of eco-friendly alternatives, but consumers are not slowing down their energy usage or the demand for these materials. Baker hopes that, in a decade, the demand for base metals and bare minerals can be sustained in part by phytomining. He acknowledges that phytomining might not be able to completely replace traditional mining, but it has many benefits. These plants grow in soils that are toxic to other plants, which allows more land to be productively used. Farmers on land with toxic soil would be able to make use of that soil with phytomining plants to create a new source of income.

     Dr. Baker is hoping this source of income can also sway nickel mining companies. Nickel mining requires coal and diesel fuels and creates acidic waste, toxic soil, and polluted waterways. These phytomining plants partially replace mines and, if planted in abandoned mines, can eradicate the negative byproducts of mining by cleaning up the soil. The revenue from these plants can be used as an incentive, along with the environmental cleanup aspect, to convince companies to consider the rehabilitation of mines through phytomining plants.

     While some people may be scared of metals and toxins that their soil might contain, Dr. Baker is refuting chemophobia by encouraging these communities to clean up their soil and make money doing it. Dr. Baker says that farmers can harvest phytomining plants on soil that contains 0.1% nickel for over 20 years. After two decades, this once-toxic soil will be devoid of nickel, but it can then be used as fertile land for traditional agricultural crops. Other opponents of phytomining have voiced concerns over a possible deforestation in order to plant the hyperaccumulating plants. These fears are unfounded because hyperaccumulating plants only grow in grassy areas that are toxic to most other plants, not in areas that could be deforested. Dr. Baker says that phytomining is “a way of putting back, rather than taking away.”

Gene Editing: Can the Utility Exceed the Fear?

Effective gene editing is becoming closer to reality as scientists develop new tools and methods to change our DNA. Arguably the most promising (and certainly the most well-known) recently developed tool for editing genes is CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats), a family of molecules which proven to be effective in controllably modifying specific segments of DNA. However, as the tool has become more known, many fears have arisen, concerning the medical and ethical dangers of gene modification. Do the potential benefits outweigh the potential risks? To answer this question, let’s first address what CRISPR is.

A computer representation of CRISPR in action

CRISPR is a two-part molecule: one part is a guide RNA to locate the desired gene, and the other is a DNA-cutting enzyme that performs the modification once on site. There are different variations being developed, but each one has those two key features. When these pieces work in tandem, they can cut and modify specific genes with a higher rate of precision, accuracy, and success than other methods.

Now, we should examine some of the fears that have risen alongside the popularity of CRISPR. The first is an ethical question on gene modification as a whole. At the most extreme end, some people’s minds jump immediately towards eugenics, the practice of purposefully controlling human reproduction to increase the occurrence of favorable genetic traits. One can see how the fear of effective genetic modification could be a step on a slippery slope in this direction, but again, this is generally the worst-case scenario and seems unlikely in the near future. A more subtle and reasonable fear is the idea that access to tools for choosing genes may lead to widening the gap between economic classes. After all, if a technology can ensure one’s children possess desirable traits, and this health technology is economically restricted (as it very well could be in the US), then new generations of the affluent could receive a measurable genetic advantage over others. This general fear has been characterized with the buzzphrase “designer babies.”

Pictured: Baby, non-designer

Before addressing the second fear, let’s discuss this first one, and why it may not pertain to CRISPR as much as it may seem at first glance. The traits that most are concerned about when discussing “designer babies” are broad, such as height, athletic ability, or intelligence. These kinds of attributes are actually very difficult to define genetically. A recent study attempted to find a genetic link for height and found that 697 genes accounted for only one fifth of height differences between subjects. Intelligence has eluded our attempts to define it sociologically and psychologically, much less quantify it genetically. Traits such as these would be extremely difficult to control, and while it is not off the table, it is certainly a long way off. The potential benefits of CRISPR would mainly be for genetic resistance to diseases, which are easier to quantify. However, if access to this is still economically restricted, it may still cause further class disparity for general health and life expectancy, so we must be wary of this danger as more about CRISPR is discovered. 

The second most common fear about the use of CRISPR is its potential danger when used on humans in general. Some fear that the technology is not efficient enough and may cause unintended cuts. Many also fear “off-target” effects; when one gene is modified for an intended effect, it may change something else unexpectedly. These fears have led many to be cautious about the use of CRISPR on humans, but some recent developments may help eliminate these worries.

A T cell, the supporting character of this CRISPR trial

In one recent trial, CRISPR was used to modify the T cells in 3 different cancer patients at the University of Pennsylvania, in an attempt to make the cells more effective at combating the cancer. The cells did not cure the cancer or become more effective at fighting it, but the trial was far from a failure. The most important result of the tests was that the cells passed the safety bar for clinical trials. The scientists facilitating the trials had a high success rate in gene cuts, the modified T cells survived for several months, and there were no adverse side effects. This is a big step towards further tests for CRISPR, suggesting that the method may be safer than originally thought. 

Recent findings on the safety of CRISPR bring us closer to eliminating the fears about its use. While it is still too early to make a definitive call, and every precaution should still be taken moving forward, it is good early evidence that the potential negative side-effects of CRISPR may be overblown. If development continues down this path, and CRISPR proves itself to be a reliable and effective way to modify genes against disease, its potential for improving human quality of life may outweigh any fears we have about using it sooner than we think.

Lab Diamonds vs Mined Diamonds: Are both Forever?

Are young couples beginning to prefer lab diamonds for their "forever" engagement rings?  Chemists can now make gem quality diamonds in the lab and young couples have taken notice.  Harriet Constable in a piece on the BBC "Future Planet" website notes that Millennials and now Generation Z – who together are the main purchasers of diamonds for engagement rings – are moving away from conventional diamonds, with nearly 70% of millennials considering buying a lab grown alternative." Both environmental and humanitarian concerns contribute to the young peoples interest.  Mining consumes a lot of energy.  On average recovering 1 carat of diamonds requires moving 250 tons of earth.  This is usually done with polluting diesel driven equipment.  Mining, particularly in developing countries where much of the mining is done, has involved abusive labor practices, and the proceeds have financed brutal gang warfare.  The industry has made efforts to curb these practices, but there is evidence they have not always succeeded.  On the other hand diamond mining provides employment in some otherwise impoverished areas.

Recovering 1 carat of diamonds requires move 250 tons of earth

Laboratory diamonds grow on a tiny seed crystal from high temperature carbon rich gasses.  The customer can buy directly from the laboratory so there is no question about complicated and possibly disturbing supply chains.  On the other hand the laboratory process is quite energy intensive.  Of course the energy from renewable sources is immediately adaptable to the process.

Making diamonds in the laboratory is quite energy intensive

On balance this is one case where young people are increasingly choosing chemistry over "natural."  While environmental and humanitarian concerns are certainly important Ms Constable notes that it might also be relevant that Meghan Markle has recently been seen wearing "a pair of glittering drop earrings embedded with diamonds that had been grown in a lab."