Category Archives: Microbes in the News

Could there really be such thing as a cellular snooze button?

algaeErin Mensch (11 AM Micro) found another article she found interesting, from Science Daily. In this story, scientists from Michigan State University identified a gene from algae in research about biofuel production that also appears to be involved in the development of human cancers. As Erin notes, it is much easier to grow things like algae in the lab, and if you can get information about human diseases at the same time, that’s a great thing. Here is Erin’s summary:

Michigan State University has discovered what they think could help solve many problems in the world such as tumor growth and oil production. A man by the name of Christoph Benning is a professor at Michigan State University and teaches biochemistry and molecular biology. He and his team were working in the laboratory trying to find a way to make algae’s capacity as a biofuel expand. In the process of trying to do that, they discovered the protein CHT7. They believe this protein is able to decide when the cells are resting or hard at work reproducing rapidly. They called it the “cellular snooze button”. This could help the oil production industry and the cancer research tremendously. The protein could enhance the production of oil and could make the tumor cells in “resting state”.

Christoph Benning explained how he was working with algae because like yeast it is easy to work with in a laboratory setting whereas many human cells are not able to grow in laboratory setting. This makes studying human disease so much harder. He says algae are able to be manipulated in the lab which helps scientists study them closely. He believes algae are able to do the same if not even more for us than yeast can. He claims he discovered this protein when noticed that when algae are essentially awake they are able to grow and when they are asleep they are able to make oil. In order to have algae able to make viable biofuel they would have to be able to grow and make oil at the same time. Benning figured out that the way to have the algae producing oil and growing at the same time is the protein CHT7. This protein would be able to tell the cells to either be awake or asleep. Depending if they were awake or asleep they would either be producing oil or growing. This is a fascinating concept and could be the start of something that changes medicine and the oil industry forever.

Benning’s next step in this process is to create an organism that does not rest and is always active. This could then help scientists able to make an enormous amount of viable oil. More importantly is could help with suppressing the growth of tumors. Ultimately this protein CHT7 could make the cancer cells not able to divide. First, they would have to look at it from the other perspective, which is how to get a cell to grow rapidly and uncontrollably. This would then explain to us about tumor growth. Once we understand tumor growth it would be easier to figure out how to prevent the rapid growth all together.  I found this article very interesting because it is always exciting when scientists find out new research that could possibly stop cancer. I hope that Benning is able to keep going with this experiment and find out more about the protein CHT7. I also found it interesting that algae have to do with oil production. I hope to read an article in the future about this being a successful protein that is able to tell tumor cells to stop rapidly dividing.

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Even Bacteria Thinks Females are Better

mosquitoAmanda Fierro (12:00 Micro) is interested in vector-borne diseases, and how microbiotia of insects might modify the behavior of the vector, and their ultimate ability to transmit disease. The relationship between pathogen, host, and vector is complicated, and other players in the web can even further complicate the rate of transmission of various diseases in a population.  See this BIO230 summary by a student from last Fall for a counterpoint to Amanda’s summary. In the meantime, here is Amanda’s story:

This topic is from an article on Science Daily based on research performed at Penn State University. The main researcher was Jason Rasgon, PhD. The topic in question for the research was Wolbachia bacteria and its connection to mosquitos and the transmission of West Nile virus. Wolbachia is a genus of bacteria that can be found in arthropods (mosquitos) and nematodes. The bacteria is a parasite that manipulates the reproductive biology of its host to improve and increase its own transmission. It is transmitted from mother to offspring. Males cannot spread Wolbachia to offspring or to any other host. Four mains methods of manipulating its host’s reproductive biology are: “1) feminization of infected males (turning genetic males into females),  2) Induced parthenogenesis (reproduction without males),  3) killing of infected males, and 4) Cytoplasmic Incompatibility (CI), the modification of sperm from infected males resulting embryonic defects and death when sperm fertilize eggs not similarly infected” (University of Rochester, 2011).  Past research has suggested Wolbachia bacteria leave mosquitos resistant to pathogens thus inhibiting mosquitos from transmitting those pathogens to humans. An example is the Dengue virus. Because of the research, mosquitos infected with the bacteria are being released into the environment as a strategy to control the Dengue virus. Research also has been done on Wolbachia’s impact on malaria. The studies suggested some malaria-inducing Plasmodium parasites could be enhanced increasing its transmission to rodents and birds.

Rasgon and his team of researchers wanted to discover the bacteria’s effect on West Nile virus. The researchers expected Wolbachia to have the same effects on the mosquito’s West Nile resistance as it did on the Dengue virus. The research team injected adult female mosquitos with the bacteria. After the bacteria was allowed to replicate within the mosquitos, they were fed blood infected with the West Nile virus. Tests showed Wolbachia did not impede the virus. In fact, the mosquitos infected had drastically higher West Nile virus infection rates than the control group after seven days from the date of infection. Rasgon points out a serious complication the results could imply—hosts rendered resistant to one pathogen by Wolbachia could become better pathways for, thus enhancing, other pathogens such as those causing malaria. The researchers also discovered the West Nile virus enhancement due to Wolbachia occurred in combination with the suppression of the genes associated with the mosquitos’ anti-viral immune response. Rasgon and his team plan to do more research to find the mechanism for the West Nile virus enhancement.

keep calmThe study is important because it is the first study to illustrate, for certain, Wolbachia bacteria enhancing a human pathogen in mosquitos. While West Nile may not be a serious illness for most, it can be deadly to some. According to CDC, about 70-80% of the people infected with the disease do not show symptoms. Those who do, can recover within weeks or months. There also is that 1% of West Nile infected people who develop serious neurologic illnesses. Ten percent of those people will die. Then there is the effect Wolbachia bacteria can have on mosquitos’ malaria resistance. Malaria is much more serious than West Nile. I have always hated insects, especially mosquitos. This gives me more reason to believe bacteria infected insects or any laboratory manipulated organisms should not be released into the environment.

New communicating molecule able to tell cancer cells to die

Cancer cells before treatment (left); cancer cells after treatment (right)

Erin Mensch (11 AM Micro) found an article in Science Daily, reporting research in the biomedical journal PLoSOne which found that the principle of “quorum sensing” from bacteria might be exploited to fight certain types of cancer cells. Using bacteria and viruses to treat cancers is a topic which has been reported in BIO230 before, but new approaches are always welcome. Here is Erin’s summary:

I read an article from the Science Daily. This article was about an experiment done by the University of Missouri. At the University, they have found a molecule that is found in bacteria and has to do with communicating to other cells. They figured out that it can change the way cancer cells act and can actually stop them from spreading. This is a huge find because cancer is so deadly because of its ability to spread so quickly.

A man by the name of Senthil Kumar said that is communicating molecule can even make the cancer cell dies immediately. Kumar explains in the article that when there is an infection somewhere in the body, the bacteria is able to tell the other bacteria what to do. This could be either to spread to this specific place or to continue rapidly multiplying. The study decided to work with pancreatic cancer cells. They grew them in the lab with these communicating bacteria cells. These molecules are known as ODDHSL. They found that after the treatment from the communicating cells that the pancreatic cells stopped multiplying, stopped spreading, and even were killed off. This is a huge deal because pancreatic cancer cells are some of the hardest cells to kill off. Kumar said that this is why they chose to use pancreatic cells because he knew if it worked for them that there is a good chance it will work in a lot of other types of cancers as well. This is a huge deal to the medical world and could be the beginning part of figuring out the mystery of so many cancers.

Kumar plans to next find a way to introduce these molecules in a more resourceful way. Once they figure out a way to do that they could then move onto animal testing. After they did animal testing and if it was successful the next step would be to test it out in humans. The problem right now is trying to find a way to be able to get these molecules to do what they did in the laboratory setting not in the laboratory. He feels pretty confident with the results he has gotten so far and where this could lead to. He said that the main thing right now is finding out if it work in animals and if that is successful we could have something very good on the way. I found the article to be extremely exciting especially because my aunt was just recently diagnosed with pancreatic cancer. Pancreatic cancer is one of the most deadly cancers there is so knowing that this molecule could make even them die off is incredible. This would be a huge accomplishment to the medical world if they could get a way to communicate with the cancer cells and tell them to die off. I am very excited to keep following this study and hope to see some more successful articles about them finding out more about this phenomenal “communicating molecule”.

Biofilm Basics and Treatment

Abby Nicodemus (11 AM Micro) found a news story via Scientific American, describing recent research published in the journal Proc. National Academy Sciences. The compounds described are being assessed for their antimicrobial properties. Because they are general inhibitors of microbial growth which operate by creating an environment unfavorable for growth, it is possible that this approach will not lead to antimicrobial resistance the way so many other compounds do. Here is Abby’s summary:

Biofilm growing on a grain of sand; image via Flickr

The focus of health care is to “[maintain] health by the treatment and prevention of disease especially by trained professionals”, so any scientific advance in the field of bacteria and disease has the opportunity to contribute to the health care field. While scanning through the current topics of microbiology, I stumbled upon an article titled “Liquid Salts Bypass Skin to Treat Infections” and it sparked my interest. Diseases and treatment of diseases being what we are studying in lecture, I thought it would make sense to discuss it in my bonus summary.

The first paragraph of this article discusses biofilms, “packed communities of microbial cells that grow on both living and inert surfaces” (Liquid Salts), which reminded me of the samples we took for the third lab. The significance of biofilms is the part they play in human infections, they are responsible for 4/5 of human infections. A large majority of microbiology focuses on human diseases and treatment. The source of infections and diseases is incredibly relevant in understanding and making scientific discoveries. Knowing more about these infections can help to lower hospital visits. It is known that biofilm infections are responsible for “almost one out of every ten visits” (Liquid Salts).

Specifically regarding biofilms, the structure of these bacterium increase their ability to fight off any treatment, including antibiotics. Skin, our protective barrier, does a more than okay job of keeping things outside of the body, making skin treatment options limited. However, innovations in science have made new categories of treatment a reality. This discovery involving salt absorption through skin widens the possibilities of fighting off infection.

Many of the ionic formulations brought forth by Mitragotri and his team showed effectiveness against treating many bacterial microfilm infections. This study has helped to tie a number of loose ends because “individual parts…have been demonstrated before, but this study draws them together in a very coherent strategy”. Ideas have been proposed involving this method, but only recently have discoveries given those ideas significance and the reality to help the millions of people affected by these diseases.

This technique decreases the amount of bacteria in the body by almost completely eliminating biofilms and minimizing the release of toxins into the human body. Currently, only specific ionic salts have been discovered and engineered to fight infection, but more research can lead to a broader spectrum of treatments for a wider range of infections. Certain salts and ions will penetrate the skin and target certain biofilms more efficiently than others.

Advances are being made in the medical field every day, but this particular discovery has the potential to change the world of disease and help many more people who suffer from bacterial infections and diseases. By eliminating biofilm infections, we can reduce the amount of money spent on treatments and the number of people admitted to hospitals for these kinds of infections will also go down.

Fuel from E. coli

Figure 1: Enzymatic synthesis of propane

Figure 1: Enzymatic synthesis of propane

Via @AnP_prof and NBC News, this is a cool story about an advance in molecular engineering of E. coli to enable this bacterium to produce propane. The news alert points to a publication in the journal Nature Communications, describing research from scientists from the University of Turku in Finland, and University College London. I’ve talked about work using microbes to make fuels in several capacities (see here, here, here, and here for some examples), and the primary challenge is to enable it to be a process that is sufficiently efficient to make it worthwhile from an energetic, and a financial standpoint.

The main issue with using bacteria to make hydrocarbon-based fuel is that they are both very hydrophobic, and as a result are toxic to cells. Forcing a cell to produce these compounds then can create a situation where the cell is essentially poisoning itself. Additionally, other attempts to engineer biosynthetic pathways for fuel production generate products that require some amount of additional purification before use, which means additional financial expense and energy expenditure prior to having a usable product. The current research, although it is in the preliminary stages and currently only has generated small amounts of propane, has regardless produced fuel that can be used in an engine essentially immediately.

The scientists took advantage of an existing pathway in E. coli that synthesizes membranes–the hydrophobic barrier that surrounds all cells–and interrupted it. Membrane precursors were shuttled into an alternative pathway that produced propane in just a few steps. To accomplish this, they introduced specific genes from at least 5 other bacterial species into E. coli, in order to construct the biochemical pathway for the synthesis of propane. The novelty of the approach is that no pathway to generate propane had been identified in any prokaryotic species. The scientists propose at the conclusion of their study several approaches for optimizing the process in order to scale it up for industrial production. One direction they suggest is to transfer the synthetic pathway into a photosynthetic microorganism, which naturally accumulates many of the additional enzyme substrates (NADPH and reduced ferredoxin) in the pathway from the figure.

There are several advantages for propane as a terminal product; it makes up the bulk of liquid petroleum gas, which is extensively used in cars, home heating systems, and elsewhere, and propane easily switches between a liquid and a gaseous state at ambient conditions. This latter property means that it can be easily removed from a culture vessel, diminishing the toxic effects that it would have on the cells that produce it. Once it has been released and collected, it can then be easily returned to a liquid state, which facilitates storage and transport. The group anticipates that with successful scale up, this process may produce fuel for vehicles within the next 5 to 10 years.

 

Update on Zombie Ants

BRAAAAAINS!

BRAAAAAINS!

Hello, and welcome to all new/returning YCP students! Additionally, welcome to all new BIO230 students–I hope everyone has had a restful and relaxing summer break. I know I sure did; I had fun during summer Micro, had a week long break, and accomplished some important Science in my spare time. One thing I did not do was update this forum. Looking back, it appears I last opened up WordPress back sometime in April. Let’s see if we can do something about that!

I found a news alert on ASM’s Microbe World site, which gives an update on the Zombie Ant story. It summarized work out of the entomology department at Penn State University, which has been studying a fascinating example of symbiosis between an insect and a fungus called Ophiocordyceps. What is most interesting about this relationship is that infection by the fungus causes behavioral changes in the host. These changes are advantageous for the fungus–the ant moves over a greater range, allowing the spores of the fungus to spread further. Obviously, infection of a colony would be a Bad Thing, leading to this observation on the phenomenon of “Social Immunity”.

Social Immunity has been observed in laboratory settings in a variety of insect species. It prevents the spread of diseases within colonies, however it has not been previously observed in field conditions. In a study published recently in PLOS One, researchers placed ants which had been freshly killed by the fungus inside one of two nests; one nest had live ants, and the second nest had no ants. The fungus-killed ants were rapidly removed from the living nest, and no further fungal infection occurred of that colony. This result suggests that effective reproduction of the fungus requires being outside of the colony.

In an expanded study, researchers examined the dynamics between the appearance of infected dead ants outside of colonies (sources of infection) and the position of foraging trails (future hosts) in several colonies over the course of 20 months. The researchers observed a consistent appearance of 14.5 cadaver ants per month per colony. Based on this low rate of infection and the lack of colony collapse, the researchers proposed that this fungal parasite represents  a “chronic” infection of these colonies. The authors suggest that the removal of corpses from the colony or ants dying in isolation outside the colony may be an essential step in the development of Ophiocordyceps to a stage that enables the fungus to infect a new host.

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