Category Archives: frontiers of chemistry

Mad Cow Disease: An Inevitable Death

A disease that has no cure and leads to an inevitable death. ‘Mad Cow Disease’ was first discovered in United Kingdom back in 1986, and for nearly 15 years the outbreak has infected up to 180,000 cattle and damaged many farm communities in the area.

Mad Cow Disease is also known as ‘Bovine spongiform encephalopathy (BSE)’, which the name itself suggests a spongy form of the cow’s brain. BSE is a slow progressing disease which targets the central nervous system of the cow causing it to act abnormally and eventually lead to its death. For unknown reasons a protein, known as ‘prion’, located in the brain of a cow, starts to change its conformation. This creates a signal which changes the conformation of other prions like a chain reaction and leads to the slow degradation of the brain. The following video provides a summary of the mad cow disease:

https://www.youtube.com/watch?v=aP-ShyyHiIc
“Mad Cow Disease is an infectious disease of cattle transmitted but by virus or bacteria, but by an abnormal form of type of protein called a prion”- Dr. Linda L. Walsh, Dept. of Psychology, University of Iowa

Transmission of this disease to human will lead to certain death, although the time length for each cases can vary from about 6 months to many years. The form of mad cow disease infected in human is known as ‘variant Creutzfeldt-Jakob Disease’ or vCJD.

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Structure of normal and abnormal prion protein, and its effect on human brain. http://www.viviennebalonwu.com/2015/07/creutzfeldt-jakob-disease-cjd.html.

This disease causes a slow degradation of the brain, creating small holes, and destroying the nervous system. As such, the symptom of this disease may consist of memory lost, lack of coordination, personality change, psychiatric issues, movements, speak and death. The transmission of this disease occurs from the direct consumption of meat infected with the abnormal prions, and possibly from blood transfusion.

“Another risk is the spread of vCJD through blood transfusions – and it is still not known exactly how many people are carriers of the disease.”  – Professor Graham Medley, University of Warwick

Although, many countries started to separate the brain, and other parts of nervous system, from the main food supply after the outbreak in the late 1990. It is possible that there are infected people who are unaware of it. Thus it increases the risk of transmitting this disease to others via blood transfusion.

“We are pretty sure that there are people out there who are infected but don’t have the disease”Professor Graham Medley, University of Warwick

Personally, I feel that there is a higher demand for research regarding prions and a cure for mad cow disease. The cause for this disease is still unknown and because of this, it is extremely difficult to prevent an outbreak from happening or to protect people against it.

 

Poramat Sucharit

The World’s Smallest Machines!

The 2016 Nobel prize in chemistry was awarded to Jean-Pierre Sauvage of the University of Strasbourg for the design and synthesis of molecular machines. As a chemistry undergraduate myself, the idea of molecular machines immediately peaked my interests. These machines are no different than the gears that rotate the wheels of our cars and spin the fans that cool the computer chips inside our computers. Now you might be asking, what’s so spectacular about that? The fact is, these machines are so small they are invisible to our naked eye; they are so tiny that even under a magnifying glass you wouldn’t even see a spec.

Jean-Pierre Sauvage and his research team first proposed the idea of molecular machines in 1983 when they successfully linked two ring-shaped molecules into one structure called a “catenane”. The linked rings acted like two gears that can move mechanically with respect to each other just like any other gear in the macroscopic world. This simple discovery has propelled the research till present day. It has now been more than 30 years since the initial proposal of molecular machines with only a two gear system.

This is the crystal structure of catenane discovered by Sauvage and his team in 1985. Released under the GNU Free Documentation License

This is the crystal structure of catenane discovered by Sauvage and his team in 1985. (c) M stone, released under the GNU Free Documentation License

Jean-Pierre Sauvage and his research team has perfected the simple two-ringed molecule into a sophisticated system of many molecules that can be designed to perform certain tasks when energy is added. As of right now, Sauvage’s team has been able to display spinning of cranks and wheels at the microscopic level. In terms of development, their systems are equivalent to the electric motors during the 1830s. Without a doubt, what Sauvage and his team have discovered is just the tip of the iceberg. These molecular machines could potentially be further developed and used for things such as new materials, sensors and energy storage systems, and I’m excited to see the applications of these molecular motors in our everyday lives. Maybe one day when molecular motors become an integral part of our world, just like the electrical motors we use now, we will look back and truly appreciate Sauvage and the other scientists for the work they have put into developing these amazingly small but complex nano-machines.

 

-Charlie Wei


References:

Press Release: The Nobel Prize in Chemistry 2016 http://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/press.html (accessed Oct 12, 2016).

Jean-Pierre Sauvage – Facts https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/sauvage-facts.html (accessed Oct 12, 2016).

Transformations of Fullerene http://www.org-chem.org/yuuki/catenane/catenane_en.html (accessed Oct 12, 2016).

Vantablack, the darkest material ever made

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(Image Credits: SURREY NANOSYSTEMS https://www.surreynanosystems.com/vantablack)

The picture above shows Vantablack, which is the darkest artificial material ever made. The coating, which absorbs almost all light, was created by British company Surrey NanoSystems to eliminate light that interfere satellites and telescopes. Let us see what is this mysterious material and how it can be used.

1.Does the darkest means the blackest?

As we known, the color is actually a result of reflected light from the object. The color shown is depend on the light frequency. The Vantablack does not actually shows any colour since there is no light reflected from it. The reason why the light can not escape is because of the structure of Vantablack. It is made of a “forest” of tiny, hollow carbon tubes, each has the width of a single atom. According to the Surrey NanoSystems website, “a surface area of 1 centimeter squared would contain around 1000 million nanotubes.” These tubes can absorb light hits, so Vantablack is called the absence of color.

 

2.Does it feels like the way it looks?

“One of the things that people often say is ‘Can I touch it?’” said by Steve Northam from Surrey NanoSystems. “They expect it to feel like a warm velvet.” However Vantablack does not feels like the way it looks. When you touch Vantablack, it just feels like a smooth surface. Because the nanotubes are minute and thin, they will collapse easily by a slight human touch. So, Vantablack is extremely sensitive  to touch, that explains why it can not yet be applied to unprotected surfaces like cars —one brush of a hand can make material lose its magic.

3.How much does it weight?

One thing interesting is that, though Vantablack is vulnerable to damage, it is super robust against other forces, like shock and vibration. This is due to the fact that every carbon nanotube is independent, and has almost no mass at all. Plus, most of the material is air. “If there’s no mass, there’s no force during acceleration,” Northam says. This makes Vantablack ideal for protected objects that might have to endure a jouncy ride, like a space rocket.

4.Any possibilities beyond its original applications?

As mentioned above, the material was initially designed for fields of frontier science, like space launch, where its ability to limit stray light makes it ideal for the inside of telescopes. But it could be applied in more daily objects with right conditions. Northam says Surrey NanoSystems has already been approached by a handful of luxury watchmakers interested in incorporating Vantablack into their wrist candy, and high-end car manufacturers want to use it in their dashboard displays for stunning visual appearance.

To my opinion, the invention of Vantablank is a great achievement for material chemistry. It suggest that the appropriate design can make the simple element show characteristics we never expected. The Vantablank give approaches to development of  carbon-related synthesis.

Video:

Reference:

Evangelos Theocharous, Christopher J. Chunnilall, Ryan Mole, David Gibbs, Nigel Fox, Naigui Shang, Guy Howlett, Ben Jensen, Rosie Taylor, Juan R. Reveles, Oliver B. Harris, and Naseer Ahmed, “The partial space qualification of a vertically aligned carbon nanotube coating on aluminium substrates for EO applications,” Opt. Express 22, 7290-7307 (2014)

 

If Organic Molecules Were Human: NanoPutians

Although killer clown sightings are the main topic of discussion these past few weeks, there is one thing aspect in chemistry that is just as weird and creepy (because it is Halloween month): NanoPutians. NanoPutians were first introduced to me in my Chem 218 class and are defined as synthetic organic molecules that resemble human forms which include but are not limited to: athletes, monarchs, bakers, and chefs.

The process begins with the synthesis of a NanoKid which provides the structural backbone for the various forms of NanoPutians. This is carried out in two multistep reactions with the upper portion which includes the head and body and the lower portion which includes the waist and legs synthesized separately as shown (1):

nanoputian-upper-body

nanoputian-lower-body

The upper and the lower portions are then joined via a Pd/Cu catalyzed coupling reaction to yield the NanoKid as shown (1):

nanokid

Microwave radiation, in the presence of a 1,2 or a 1,3 diol, is the methodology for the “head-conversion reaction” of a NanoKid to yield the series of NanoPutians (1). Depending on the reaction conditions, the NanoPutian could resemble that of an athlete (NanoAthlete), a pilgrim (NanoPilgrim), a Green Beret (NanoGreenBeret), a jester (NanoJester), a monarch (NanoMonarch), a Texan (NanoTexan), a scholar (NanoScholar), a baker (NanoBaker), or a chef (NanoChef) as shown (1):

nanokid-conversion-reaction

Furthermore, if you are not satisfied with the diversity, miscellaneous reactions that do not implement a NanoKid backbone can yield NanoToddlers and NanoBalletDancers. A NanoPutian Chain can also be synthesized, with modifications to the synthesis of the upper portion of the NanoPutian to yield an AB polymer configuration, to resemble individual NanoPutians “holding hands” and to symbolize multinanolism and peace on NanoEarth (okay I’ll admit I made that up) as shown (1):

nanoputian-chain

Now you may ask yourself: “Who funds this kind of research?”, “Why would anyone invest their time on this?”, or “What is the significance in learning about NanoPutians to the scientific community?”. Truth be told, there is no known significance (yet), in terms of chemical and practical applications, which may explain the limited research in this area (2). However, the synthesis of NanoPutians contributes a significant role in aspiring the younger generations in science and more specifically, the field of chemistry (2). And sometimes, we tend to forget how important that really is. If scientific advancements are to be made in the future (and one can only predict what the future will look like), the younger generations must be inspired by science and motivated to learn more in order to solve the problems and answer the questions, that we could not, about the world we live in.

-Andrew Siu

Chem 300 Section 109

References

Chanteau, S., Tour, J. Synthesis of Anthropomorphic Molecules: The NanoPutians. Journal of Organic Chemistry 2003, 68, 8750.

NanoPutians. Wikipedia. https://en.wikipedia.org/wiki/NanoPutian (accessed Oct. 8, 2016).

 

 

 

 

 

 

Graphene Batteries: A Better Alternative

There’s been a lot of fuss recently regarding the new phones. The Samsung Note 7 and the iPhone 7, particularly, seem to exhibit a major flaw: They tend to explode. Well, exploding may be overstating the actual situation, as most of the time they just catch on fire, but it is still quite a major inconvenience.

So why is this happening? Its not like lithium-ion batteries are a new technology, right?

Well, it is true that companies have been using these batteries for a long time now, but the problem has to do with how companies have began to stretch out the limits of the design in order to satisfy its customers.

The lithium-ion batteries work like this:

lithium-ion-battery-powering-device

Simplified diagram of a Lithium-ion battery. (Image courtesy of Sustainable-nano.)

Where the solution inside the battery helps move the electric charge in and out of the battery.

This these batteries, there are certain limits such as size and charge that dictate the safety and stability of the battery. Therefore, when the companies begin to push the limits of the battery design so that they can give a longer charge, and use less space. What this creates is a very unstable battery, and a very unhappy customer.

So what can we do to fix this?

Meet the Graphene battery.

Graphene is a material that has many wonderful properties. It’s lightweight, conducts electricity extremely well, and is incredibly stable, forming a sturdy yet flexible material. The best part is: it is found in everyday items such as pencils and charcoal, so it won’t be a limited resource either.

Graphene batteries work by using layers of graphene to act as the plates that move electricity in and out of the battery. By using graphene instead of lithium or other metal plates, we fix two major problems:

  1. Graphene holds a much larger amount of charge, and is able to charge up in just a fraction of the time. Pictured below is the G-King graphene battery. At the size of a regular smartphone, it holds more than 3 times the charge of a regular phone battery. Best of all, it can be fully charged in fifteen minutes.

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    The G-King, in all its glory. (Image courtesy of Graphene-info.)

  2. Since graphene is so safe and flexible, it opens up new venues of battery design. Graphene batteries are made in all sorts of shapes and sizes, enabling batteries in all sorts of convenient places.

    vorbeck-vor-power-img_assist-400x216

    A bag strap with an attached graphene battery inside as a easy to use recharging station. (Image courtesy of Graphene-info.)

Although most graphene products are still under development, expect to see some great results coming through the next couple of years. I, for one, will be sure to pick these up as soon as they hit the general market. In the meantime, you can watch this video about the unveiling of the G-King battery.

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-Dennis Lin, Undergrad Chemistry

Zika Virus impairs Infant’s brain development

What is Zika? Zika is a virus passed by a bite of an infected yellow fever mosquito  (1). Adults infected with Zika virus can develop several symptoms. For instance, headache, rash, fever, red eyes and muscle pain. Indeed, not only adults can be infected by the Zika virus. Pregnant women infected with Zika virus can also pass it down to their fetus.

Joseph Gleeson,a neuroscientist from Rockefeller Univeristy in New York City,  suggested infants infected with Zika virus are very likely to be born with abnormally small heads called microcephaly (4). A group of researchers conducted an experiment to understand how Zika virus caused impairment in cerebral cortical development, an area of the brain associated with the function of thoughts and actions. First, the researchers infected both neural progenitor cells (NPCs) and mature cortical neurons with Zika virus (2). Neural progenitor cells, like stem cells, that are capable of differentiating into neural cells (3). While, cortical neurons are nerve cells found in the largest region of the brain that is responsible for the complex activities, such as thoughts, perceptions, voluntary movements and more (3). The experimental results showed there were more cell deaths in infected NPCs than mature cortical neurons. Thus, the scientists claimed the results provide a plausible pathway showing how fetus’s brain is infected by Zika virus.

Figure 1: The comparison of infant's head size without Zika virus versus with Zika virus

Figure 1: The comparison of infant’s normal head size to an infant infected with Zika virus. Author: Tani Source: Picture uploaded by original photographer

zika-map

Figure 2: The map showing the spread of Zika virus. Author: Lizzie Dearden; Source: Picture uploaded by original photographer

Zika virus has been reported to be an alarming issue in Brazil, Mexico, some areas in the United States and more (1). At this stage, there is no cure or vaccine to treat Zika virus. However, wearing long-sleeved shirts and long pants regularly can minimize the chance of getting bitten by a Zika-infected mosquito. In addition, carry insect repellent all the time is another way to avoid getting infected with Zika virus. It is strongly encouraged to consult the doctor for advice if an expectant mother is infected with Zika virus. Lastly, try to avoid traveling to areas reported with active Zika virus transmission.

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References:

1. U.S Department of Health and Human Services. Centers for Disease Control and Prevention: Zika Virus. https://www.cdc.gov/zika/about/overview.html (accessed on Oct 2nd, 2016).

2.Miner, J.J & Diamond, M.S. Cell Stem Cell: Understanding How Zika Virus Enters and Infects Neural Target Cells. Science Direct. 2016, 18, 559-560.

3. Nature. Neural progenitors. http://www.nature.com/subjects/neural-progenitors (accessed on Oct 2nd, 2016).

4. Society for Science and the Public. Brain Health: Zika can damage the brains of even adults. https://www.sciencenewsforstudents.org/article/zika-can-damage-brains-even-adults (accessed on Oct 2nd, 2016).

Photo source:

1. Copyright information: http://pregnancywellnesstips.com/pregnancy-wellness-symptoms-prevention-treatment-of-zika-virus-during-pregnancy/

2. Copyright information: http://www.independent.co.uk/life-style/health-and-families/health-news/zika-virus-uk-america-europe-symptoms-cure-pregnant-women-microcephaly-a6851126.html

Bacteriophages: A Possible Alternative to Antibiotics?

What would happen if we ran out of antibiotics to use against bacteria? Antibiotic resistance is known to be one of the major concerns among doctors and scientists around the world since, it’s our primary defense against bacterial infections. Without these antibiotics, it’d be virtually impossible to treat many types of diseases or even perform surgeries.

The quality of healthcare has significantly improved over the centuries as more people have access to treatment, medicine, and antibiotics. However, it has also increased the risk of wrong applications of drugs, allowing the bacteria to develop defense mechanisms to different types of antibiotics. In fact, there has been a dramatic increase in the number of scientific reports about different drugs resistance cases.

Antibiotic resistance occurs through process known as ‘Natural Selection’, where the bacteria has evolved and is no longer affected by the antibiotics. A stand-out candidate as an alternative for antibiotics is known as bacteriophages.

‘Alternative treatments are urgently required and we are investigating one such treatment – the use of bacteriophage.’

  • Robert Atterbury, Phage Biotechnology, University of Nottingham.                             
Resistance bacteria survived the treatment of antibiotics, thus able to reproduce and increase in numbers.

Resistance bacteria survived the treatment of antibiotics, thus able to reproduce and increase in numbers. <http://www.reactgroup.org/toolbox/mutation-and-selection/>. Photo credit: Uppsala University

‘Bacteriophage, or phage is a virus that infects bacteria, so these don’t infect human cells- they are specialised and only infect bacteria’

  • Brent Gilpin, Science Leader, Environmental Science Group, New Zealand.
Bacteriophage attached itself to the bacteria before releasing its DNA inside.

Bacteriophage attached itself to the bacteria before releasing its DNA inside. <http://www.news-medical.net/news/20151202/Bacteriophage-therapy-an-alternative-to-antibiotics-An-interview-Professor-Clokie.aspx>. Photo credit: News-Medical.net team

Bacteriophage or phage infects the bacterial cell by first recognizing the bacteria and then attaching itself to the bacteria’s surface (cell wall). After the phage has penetrated the cell wall, entering the bacteria, and it releases its DNA inside. This DNA merges itself with the bacterial DNA causing the bacteria to produce proteins for the phage. Other chain reactions occur which causes the bacteria cell to produce more phages and eventually bust out, causing the bacteria to die. – This process is shown in the following video:

‘Bacteriophage Life Cycle’

This method is currently being adopted by many industries including food protection against food-borne disease, and medical treatment for both animal and humans. Furthermore, there are many advantages in using phage therapy; for example the phages are target specific, thus only attacking bacteria with a certain structure. With the right phage, it’s harmless to humans and since, phage is found naturally throughout the environment, there are several types of phages that can be studied and used. In addition to this, phage can be genetically modified to reduce their side effects, harmful abilities, or any unnecessary features. With this, it’s possible that phages can be used as an efficient and effective treatment against bacteria.

I strongly believe that bacteriophage is a potential alternative for antibiotics due to its ability to target specific bacteria, its harmless nature to humans, and its ability to be genetically engineered. Moreover, it can also be used in many industries as a safety precaution, in medical treatments, or even scientific research.

 

Poramat Sucharit

Techniques Preventing Cancer Metastasis in Development

When I was 8 years old, my friend’s mother was diagnosed with breast cancer. Several years later her aunt was also diagnosed with breast cancer. For my friend, developing cancer is not imminent, however the thought of developing cancer is a terrifying idea for her. There is no doubt that almost everyone knows someone in their life who has been diagnosed by cancer, whether it be a family member, a friend, or an acquaintance. In my opinion, to fight against cancer the only way is to entrust the development of cures to the scientific community.

Cancer is menacing disease caused via changes to genes that control the way cells function. In the 21st century cancer has been the most renowned disease. The mortality rate of this disease is no laughing matter as an estimated 1,685,210 patients will be diagnosed with cancer and of those, 595,690 will die during 2016 in the United States alone. While many researchers are feverishly looking for cancer cures that kills cancer, others have been investigating methods to halt cancer from spreading throughout a patient’s body. MIT’s Natalie Artzi, a research scientist at MIT’s Institute for Medical Engineering and Science (IMES), and Tel-Aviv University’s Noam Shomrom have developed a new technique that may help prevent cancer metastasis.

Cancer Metastasis

Cancer Metastasis, courtesy of Wikimedia Commons

Metastasis is the spread of malignant cells from one organ or part of the body to another. Artzi and Shomrom’s new gene therapy technique involves applying microRNAs to cancer tumours. MicroRNAs are cellular RNA fragments that prevents the production of a particular protein. In their research Artzi and Shomrom identified that the protein Palladin plays a key role in the metastasis of breast cancer cells. Their experiments led to the discovery that miR-96 and miR-182, types of microRNAs, decreased the expression of Palladin, thus hampering the cancer cells capabilities to spread.

microRNA

microRNA, courtesy of Andres Zapata https://vimeo.com/52646065

 

With this new gene therapy technique in development, many types of cancers can be halted so long as the correct microRNAs are applied to the cancer sites. I  feel that this research is an immense step towards defeating cancer. Artzi and Shomon’s technique coupled with already known cancer treatments, such as chemotherapy,  can effectively halt the metastasis of early-stage cancer tumours. Thus, potentially saving thousands of patients in the United states, and millions around the world. Nonetheless, cancer would likely never be extinct until a definitive cure is found. However as members of the scientific community, we must do our best in following Artzi and Shomon’s footsetps by developing new techniques and treatments in hopes of saving the lives of people we know.

– Nelson Yu

UBC Researcher Developing Marijuana Breathalyzer

Earlier this year at UBC Okanagan’s Advanced Thermo-Fluidic Laboratory, engineering professor Mina Hoorfar and PhD student Mohammad Paknahad developed a breathalyzer for tetrahydrocannabinol (THC), the active ingredient in marijuana. While attempting to make an affordable miniature gas chromatography-mass spectrometry (GC-MS) device, it occurred to them that, with marijuana becoming legalized in more parts of the world every year, there was a growing market they could to tap into. When testing out their device as a THC detector was a success, they started to develop their device specifically as a marijuana breathalyzer.

Unlike traditional breathalyzers, this device utilizes GC-MS and a computer, and is therefore highly adaptable – it can easily be used to search for concentrations of a variety of chemicals. Some other uses they’ve thought of for the device include analyzing the characteristics of wine, checking your own blood alcohol content, monitoring glucose levels in diabetic people, and finding gas leaks along pipelines.

Gas Chromatography-Mass Spectrometry schematic, courtesy of Wikimedia

Gas Chromatography-Mass Spectrometry schematic, courtesy of Wikimedia (https://upload.wikimedia.org/wikipedia/commons/b/b9/Gcms_schematic.gif) Gas is injected into the column, where it sorts itself into groups based on properties such as polarity and molecule size. The groups of molecules pass through the mass spectrometer, which analyzes how much of each chemical there is.

Mina Hoorfar specializes in microfluidics, the field of manipulating tiny amounts of gas and liquid using their chemical properties. In this device, the exhaled breath is channeled through a column that is only one micrometer thick, where the chemical components are separated by their properties and analyzed using the same processes as in regular GC-MS. The results are then sent via Bluetooth to a computer or smartphone, showing the user exactly what is in their breath. The device would cost about $15 to build – incredibly cheap for a GC-MS device, which often cost thousands of dollars – and Hoorfar says that she is working with a lab instrument company to bring the device to the market.

~ Nat Shipp

Researchers observe when bacteria develop resistance to drugs

Microbiologist Michael Baym and colleagues of Harvard Medical School has developed a new experimental setup  to watch how bacteria adapt the drug and evolve antibiotic resistance, reported in the Sept. 9 Science. The experimental setup pictures shows step by step how could those minute creatures found in gardens grow up to strong drug fighters.

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Fig. 1 An experimental device for studying microbial evolution in a spatially structured environment.

(A) Setup of the four-step gradient of trimethoprim (TMP). Antibiotic is added in sections to make an exponential gradient rising inward. (B) The four-step TMP MEGA-plate after 12 days. E. coli appear as white on the black background. The 182 sampled points of clones are indicated by circles, colored by their measured MIC. Lines indicate video-imputed ancestry. (C) Time-lapse images of a section of the MEGA-plate. Repeated mutation and selection can be seen at each step. Images have been aligned and linearly contrast-enhanced but are otherwise unedited.

It is very common for scientists to study bacteria in petri dishes or flasks, a small closed space which includes all experimental materials together, and see how bacteria develop mutant to face and overcome the new challenge of environment.

Although Baym and colleagues did something different as they said, “Inside that flask, in order for a new strain to evolve, the new mutant has to be more fit than everything around it. But in nature, we see a second dynamic: You don’t necessarily need to be more fit than everything around you. You just need to make it into a new environment.”

In order to simulate the natural environment better, they modeled a environment for diversity, an experimental device called the microbial evolution and growth arena (MEGA)–plate was used. By placing different concentrations of trimethoprim or ciprofloxacin (both are widely-used antibotics) in different parts, some of the Escherichia coli bacteria was then observed to have incredible ability to endure a thousand times concentrated antibiotics. However, this sometimes also makes the bacteria spread slowly, which means it may not make them become more competitive in nature selection.

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Fig. 2 Initial adaptation to low drug concentrations facilitates later adaptation to high concentrations.

(A) Frames from a section of the TMP intermediate-step MEGA-plate over time (TMP, movie S4; CPR, movie S5). The first frame showing a mutant in the highest band is indicated by a blue box. (B) Rates of adaptation in the intermediate-step experiments across TMP and CPR, showing the necessity of intermediate adaptation for the evolution of high levels of resistance. Error bars show the appearance times of multiple lineages in the highest concentration. Because the intermediate step with no drug puts the highest and lowest concentrations adjacent, it serves as both the highest and lowest intermediate steps (dashed line).

Sam Brown, a microbiologist at the Georgia Institute of Technology in Atlanta who was not in Baym’s group, believes that the bacteria are “climbing this impossible mountain of antibiotics.” Baym and his colleagues thinks this experimental setup could be useful for microbial researches interested in particular environment with special restrictions.

This research suggest that the traditional method is not always the best for new experimental conditions,  the new methodology can be developed and applied to fit the real situation. The relative simplicity and ability to visually demonstrate evolution makes the MEGA-plate a useful tool for science education.

Video:

Reference:

M. Baym et al. Spatiotemporal microbial evolution on antibiotic landscapes. Science. Vol. 353, September 9, 2016. doi:10.1126/science.aag0822