Tag: bacteria’


 - by KitchenPantryScientist

A soil bacterium we swabbed last spring on the set of Twin Cities’ Kare11 News is headed to the International Space Station! Even though we collected it here in Minnesota, Streptomyces kanamyceticus (we’ll call it S.kan for short) was first isolated from dirt in Japan.

It’s a very cool bacterium. Not only does it grow in really interesting colonies like the ones you see in the photo below, but it produces an antibiotic called Kanamycin that’s widely use in research, industry and medicine. Our #MinnesotaMicrobe takes off on March 16th from Kennedy Space Center on a SpaceX-3 rocket! Follow the mission on Project MERCURRI’s website, here on my blog, or using the #spacemicrobes hashtag on Twitter.

After we sent our sample off in the mail, it was swabbed onto bacterial growth medium and these cool little colonies were grown by the scientists from Project MERCURRI, alongside other samples swabbed from NFL and NBA stadiums, NASA spacecraft, and even from a candy jar at Kare11’s sister NBC studio at the Today Show. Around 40 of the samples were chosen to travel to the International Space Station (ISS) for a “Superbowl” of microbes. Scientists want to study how the bacteria grow and change in space and want to get the public excited about the project.

Why should we care how bacteria grow on the ISS, or on any spacecraft?

Microbes behave oddly out in space, and when humans exit Earth’s atmosphere, we carry microscopic  inhabitants along with us. Tiny terrestrials (mostly bacteria) outnumber our bodies’ own cells by about ten to one, and microbes too small to see with the naked eye cover everything you around you, assuming you don’t live in a sterile bubble.

Pseudomonas aeruginosa, a funny little bacterium that smells like grapes and loves water, grows differently in microgravity. These bacteria form slime layers called biofilms and can cause problems for extraterrestrial toilets and water systems, like the ones on the International Space Station (ISS). Here on Earth, P. aeruginosa can make people who have been badly burned and people with cystic fibrosis (CF) really sick.

NASA also discovered that spending  time on the International Space Station made Salmonella bacteria, which cause food poisoning, more virulent. In other words, they can make you sicker.

By studying what happens to terrestrial bacteria in space, scientists can discover new ways to fight infectious disease on Earth and hope to prevent mechanical and medical disasters on future space missions. Microbes may even offer ways to clean up waste in space or generate new medications mid-mission. After all, it will take a long time to get to Mars, and it may be a one-way trip for the first humans to travel there!

If you want to make your own microbial growth plates at home to see what’s growing around your house, you can find directions and a video on how to do it here. In the next week or so, I’ll post instructions for a cool new microbiology experiment that I’ve been thinking about. 



Beneficial Bacteria: Our Best Defenders?

 - by KitchenPantryScientist

Did you know that we have ten times more microbes in our bodies than human cells?  It may sound gross, but these microbes are often more friend than foe and keep us healthy  in return for a little space to call their own.

There was a fantastic article in yesterday’s Science Times about microbiomes- what scientists call the collection of microorganisms colonizing our bodies.  The study of microbiomes has intensified in recent years and scientists are trying to catalog some of the bacteria we carry.

I eat yogurt filled with healthy, or beneficial, bacteria on a daily basis to keep a healthy population of these little helpers living in my gut.  This keeps the bad bacteria from finding a place to take hold.  A more extreme version of this was mentioned in the Science Times article, where a woman dying of an intestinal infection caused by pathogenic, or bad bacteria was saved when bacteria from her husband’s intestines was introduced into her large intestine.  Within hours, the good bacteria had “kicked” the bad bacteria out, taking over residence.

I also learned that babies born by C-section (like my three kids) are more prone to skin infections and asthma, possibly due to the fact that coming from the sterile amniotic sac, they are colonized by bacteria from adults’ skin rather than that bacteria from their mother’s birth canal.  In fact, people with asthma have a different set of lung microbes than healthy people and obese people have a different set of bacteria in their guts than people of normal weight.

You’ve heard that kids on farms and are exposed to dirt have healthier immune systems than city kids?  It’s not the dirt itself, but the microbes in the dirt giving them their immune systems a boost.

There are years of hard work in the lab ahead of scientists to validate their beliefs that beneficial bacteria may one day be a weapon in the arsenal against infectious disease, but in the meantime, I plan to keep eating my yogurt and letting my kids play in the dirt.

Jurassic Park- Closer Than We Think?

 - by KitchenPantryScientist

When I told my husband that scientists at the J.Craig Venter Institute had assembled a funtioning bacterium from bottles of chemicals, he said exactly what I was thinking.  “It’s like The Stand.”  Even if you’re not a Stephen King fan, you’ve probably heard of his novel where a genetically engineered strain of the flu virus wipes out almost every human on earth.

USA Today, on the other hand, said “The long-anticipated advance, reported in the journal Science, is a $40 million milestone in the nascent field of “synthetic biology” and points towards a future of designer microbes manufacturing fuels, chemicals and materials.”

The news that a synthetic bacterium has been created comes as no surprise to most scientists.  Even when I worked in a lab ten years ago, we cut and pasted bacterial DNA together on a regular basis.  We also synthesized  relatively short pieces of DNA by pushing buttons on a machine.  The technology has vastly improved since then, and entire bacterial genomes have been sequenced.  Scientists know exactly what it takes to make a functioning bacterial cell.

Some good and bad uses for synthetic biology immediately spring to mind:

Good things:  Scientists may be able to design bacteria that specifically target certain areas of the human bodies, so that the bacteria could colonize those areas (say, the intestine) and produce and deliver drugs to specific organs without causing harm.  You could even turn drug delivery on and off by putting “inducible promoters” which are basically on/off switches, in front of the genes for drug production.  You could possibly use the technology to deliver chemotherapy directly to tumors too, if you could create bacteria that recognize and bind to certain proteins produced by tumor cells.

Bad, bad things:  Bioweapons.  Scientists could potentially piece together nasty bacterial bioweapons that could survive sunlight and even radiation. (Most natural bacteria are relatively fragile and difficult to “disperse” or spread through the air.)

Nature has some controls of her own.  Bacteria must contain certain elements to survive and replicate, and sometimes putting foreign DNA into a bacterium will kill it.  There are also size limits.

We can only hope that the good that comes from this technological breakthrough outweighs the bad.  Later today, I’m planning to pre-order tickets for an amusement park where you’ll be able to see real live dinosaurs in about 20 years.

Dog Food Anyone?

 - by KitchenPantryScientist

First of all, I have nothing against real ground beef.  That is, I will eat beef that has been ground by my local butcher or trusted grocer.  I love a good burger.

However, starting today, I refuse to eat ground beef from an unknown source (i.e. fast food restaurants and big chain grocery stores.)  Not only does the ground beef industry refuse to allow retesting of their meat  (they won’t even sell it to stores who retest it,) I just read that one company is taking parts of cow that are considered unusable, treating the beef  “trash” with ammonia gas to kill harmful bacteria that tend to contaminate those cow parts, and selling it to be mixed with higher quality ground beef to make it cheaper for restaurants and schools (yes, schools!)  This disgusting meat product, which doesn’t list ammonia as an ingredient, although it remains following treatment, may still harbor dangerous bacteria.  It’s unbelievable.

I’m not touching ground beef from an unknown source or letting my kids eat it until the beef industry and the U.S.D.A get their act together.  I’d suggest you do the same.  Maybe if we all boycott their substandard, potentially dangerous product, they’ll stop trying trying to feed us beef products that used to be made into dog food.

For a more complete story, read today’s New York Times article at http://www.nytimes.com/2009/12/31/us/31meat.html?_r=1&hp