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Superbugs by Jerome Groopman, New Yorker:
Great article. Related: Bacteria Survive On All Antibiotic Diet - Bacteria Can Transfer Genes to Other Bacteria - New Yorker on CERN’s Large Hadron Collider - posts on health related topics
Nebraska Firm Expands Recall of Beef Products Due To Possible E. coli O157:H7 Contamination, USDA
Another example of the questionable state of food safety in the USA.
Related: USDA’s failure to ensure safe beef supply - Mad-cow testing gets scathing review - Scientists Knock-out Prion Gene in Cows
Gator Blood May Be New Source of Antibiotics
For the study, the researchers extracted proteins known as peptides from white cells in alligator blood. As in humans, white cells are part of the alligator’s immune system. The researchers then exposed various types of bacteria to the protein extracts and watched to see what happened.
In laboratory tests, tiny amounts of these protein extracts killed a so-called “superbug” called methicillin-resistant Staphylococcus aureus, or MRSA. The bacteria has made headlines in recent years because of its killing power in hospitals and its spread among athletes and others outside of hospitals.
The extracts also killed six of eight strains of a fungus known as Candida albicans, which causes a condition known as thrush, and other diseases that can kill people with weakened immune systems.
Related: Entirely New Antibiotic Developed - Soil Could Shed Light on Antibiotic Resistance - articles on the Overuse of Antibiotics
Bacteria make major evolutionary shift in the lab
Lenski and his colleagues are now working to identify just what that earlier change was, and how it made the Cit+ mutation possible more than 10,000 generations later.
Related: People Have More Bacterial Cells than Human Cells - Understanding the Evolution of Human Beings by Country - E. Coli Individuality
Bacteria “Feed” on Earth’s Ocean-Bottom Crust
“We scratched our heads about what was supporting this high level of growth,” Edwards said. With evidence that the oceanic crust supports more bacteria than overlying water, the scientists hypothesized that reactions with the rocks themselves might offer fuel for life.
Why doesn’t this stuff make the news over what some celebrity did or politician said… (well I must admit I am just guessing since I don’t actually watch the news or read the mass media much - other than some science, investing or economics content). Oh well, at least you get to read the Curious Cat Science blog and find out about some of the cool stuff being learned every day.
Related: Life Far Beneath the Ocean - Clouds Alive With Bacteria - Bacterium Living with High Level Radiation - Giant Star Fish and More in Antarctica
Where it is left untreated, Hansen’s disease is a leading cause of disability and devastating deformity. It remains endemic in Bangladesh, India, Brazil and elsewhere. In the United States, roughly 6,000 people have the disease. One hundred to two hundred new cases are reported annually, and, like BB Blanchard, about two dozen of those new patients have never been beyond U.S. borders.
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How transmission occurs is a mystery. Humans and the armadillo are the only two creatures known to get the disease. No one knows where the microbe hides in nature, although the suspicion is that the leprosy mycobacterium may be airborne like its bacterial cousin, tuberculosis.
Most people think of leprosy as a skin disease. But the rash that BB Blanchard had and the disfiguring lesions often associated with it are just a symptom. The mycobacteria burrow into nerves, where they often remain undetected for years or even decades.
Related: Gates Foundation and Rotary Pledge $200 Million to Fight Polio - Skin Bacteria
WCI student isolates microbe that lunches on plastic bags
After three months of upping the concentration of plastic-eating microbes, Burd filtered out the remaining plastic powder and put his bacterial culture into three flasks with strips of plastic cut from grocery bags. As a control, he also added plastic to flasks containing boiled and therefore dead bacterial culture.
Six weeks later, he weighed the strips of plastic. The control strips were the same. But the ones that had been in the live bacterial culture weighed an average of 17 per cent less.
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The inputs are cheap, maintaining the required temperature takes little energy because microbes produce heat as they work, and the only outputs are water and tiny levels of carbon dioxide — each microbe produces only 0.01 per cent of its own infinitesimal weight in carbon dioxide, said Burd.
“This is a huge, huge step forward . . . We’re using nature to solve a man-made problem.” Burd would like to take his project further and see it be used. He plans to study science at university, but in the meantime he’s busy with things such as student council, sports and music.
Related: Bacteria Survive On All Antibiotic Diet - Microbes May Use Chemicals to Compete for Food - Siemens Westinghouse Competition Winners 2005

Bacteriophages: The Most Common Life-Like Form on Earth
Photo credit: Wikipedia Electron micrograph of bacteriophages attached to a bacterial cell. These viruses have the size and shape of coliphage T1.; Insert: Mike Jones
Related: webcast of Bacteriophage T4 - types of microbes - What are Viruses? - Amazing Science: Retroviruses - Using Bacteria to Carry Nanoparticles Into Cells
Expressing Our Individuality, the Way E. Coli Do by Carl Zimmer
In our noses, nerve cells can choose among hundreds of different kinds of odor receptors. Each cell picks only one, and evidence suggests that the choice is controlled by the unpredictable bursts of proteins within each neuron. It’s far more economical to let noise make the decision than to make proteins that can control hundreds of individual odor receptor genes.
Identical genes can also behave differently in our cells because some of our DNA is capped by carbon and hydrogen atoms called methyl groups. Methyl groups can control whether genes make proteins or remain silent. In humans (as well as in other organisms like E. coli), methyl groups sometimes fall off of DNA or become attached to new spots. Pure chance may be responsible for changing some methyl groups; nutrients and toxins may change others.
Related: Androgenesis - Sick spinach: Meet the killer E coli - Parasite Rex
All the World’s a Phage by John Travis:
In the April 18 Cell, Hatfull and his professional and teenage collaborators describe the genomes of 10 soil-dwelling bacteriophages that they had isolated. Of the more than 1,600 genes that the team identified, about half are novel, that is, they don’t match any previously described genes in any other organism.
Science is full of amazing new frontiers. Some other amazing stuff: Thinking Slime Moulds - Tracking the Ecosystem Within Us - Retroviruses - Energy Efficiency of Digestion - One Species’ DNA Discovered Inside Another’s
The More We Know About Genes, the Less We Understand by Carl Zimmer
E. coli’s network allows it to respond quickly to the challenges it meets, from starvation to heat to the loss of oxygen. It can rapidly reorganize itself, switching on hundreds of genes and switching off hundreds of others. What makes this network all the more impressive are the feedback loops that keep it from spinning out of control. When one gene switches on, for example, it may make a protein that shuts down the gene that switched it on in the first place.
Yet even as scientists uncover this network, they discover yet another mystery. In the latest issue of Nature, scientists reported an experiment in which they wreaked havoc with E. coli’s network. They randomly added new links between the transcription factors at the top of the microbe’s hierarchy. Now a transcription factor could turn on another one that it never had before. The scientists randomly rewired the network in 598 different ways and then stepped back to see what happened to the bacteria.
You might expect that they all died. After all, if you were to pop open the back of an iPod and start linking its components together in random ways, you’d expect it to crash. But that’s not what happened.
About 95 percent of the rewired bacteria did just fine with their new networks. They went on with their lives, feeding, growing and dividing. Some even performed better than microbes with the original wiring, under some conditions.
Related: Programing Bacteria - Sick spinach: Meet the killer E coli - Bacteria Can Transfer Genes to Other Bacteria - Evolution is Fundamental to Science - genes tagged posts
“Healing clays” hold promise in fight against MRSA superbug infections and disease
Also listen to a podcast with the researchers, Lynda Williams and Shelly Haydel, that provides much more detail. The Science Studio podcasts from Arizona State University provides great science podcasts.
Related: Soil Could Shed Light on Antibiotic Resistance - Entirely New Antibiotic Developed - Science Webcast Directory - NSF Awards $50 Million for Collaborative Plant Biology Project (University of Arizona)
Bacteria Survive on All-Antibiotic Diet
Related: Bacteria Can Transfer Genes to Other Bacteria - People Have More Bacterial Cells than Human Cells - Soil Could Shed Light on Antibiotic Resistance - FDA May Make Decision That Will Speed Antibiotic Drug Resistance - Drug Resistant Bacteria More Common

This image is from the Eye of Science web site (which has many great images):
Other species of Geobacter bacteria can eliminate petroleum contamination in polluted water and convert waste organic matter to electricity. Geobacter sp. are anaerobic bacteria (living without oxygen) that use metals to gain energy in the same way that humans use oxygen. Coloured scanning electron micrograph, Magnification: x3,600 and x4,800
Related: Geobacter metallireducens at the microbe wiki - The Art and Science of Imaging - 2006 Nikon Small World Photos - Bacterium Living with High Level Radiation - Art of Science at Princeton (2005) - Get Your Own Science Art
But even though microbes essentially rule the Earth, scientists have never before been able to conduct comprehensive studies of microbes and their interactions with one another in their natural habitats.
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Because microbes are an ecosystem’s first-responders, by monitoring changes in an ecosystem’s microbial capabilities, scientists can detect ecological responses to stresses earlier than would otherwise be possible–even before such responses might be visibly apparent in plants or animals, Rohwer said.
Evidence that viruses–which are known to be ten times more abundant than even microbes–serve as gene banks for ecosystems. This evidence includes observations that viruses in the nine ecosystems carried large loads of DNA without using such DNA themselves. Rohwer believes that the viruses probably transfer such excess DNA to bacteria during infections, and thereby pass on “new genetic tricks” to their microbial hosts. The study also indicates that by transporting the DNA to new locations, viruses may serve as important agents in the evolution of microbes.
Related: Archaea, Bacteria, Fungi, Protista and Viruses - Microbe Food - Bacterium Living with High Level Radiation
Engineered Protein Shows Potential as a Strep Vaccine
Related: New and Old Ways to Make Flu Vaccines - MRSA Vaccine Shows Promise - New Approach Builds Better Proteins Inside a Computer
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