October Update

Bought a standard poodle puppy.  Bringing him home October 5, so October will be full of housebreaking, and FUN.



Entries in bacteria (9)


Who Shall Inherit the Earth?

Years ago, we used to predict that if a disaster wiped out humans and lots of other animals, rats and cockroaches would survive.  Supposedly, those two types were indestructible.

I think we were mistaken.  I think we were wrong.  I think bacteria not only will inherit the earth, they already have.  It is an illusion that we are the masters of this planet.

We are in the process of "discovering" that we cannot live without the many species of bacteria that inhabit our bodies.  This burgeoning discovery is on a par with the discovery of DNA.  The sub-discoveries promise to be in the bazillions.  Even The New Yorker (Oct. 22) is interested, with an article called "Germs Are Us."

Now NewScientist has an article, "Electrical Bacteria," about bacteria that transfer electrons from one individual to another.  That is, they establish electrical currents.  These bacteria line up to form a continuous filament, and pass electrons over distances that are enormous relative to the size of the actual individual cells.  This may be a method of communication, much like the purposes of neurons in animals.

This is just one more wonder to stack up with all the other wonders.  More on this later; please stay tuned!


Love Me, Love My Bacteria

My June 19 post was about the exciting study of our microbiomes.  A microbiome is the entire assemblage of bacteria that live in any one human being, or other animal.  Your microbiome is different from mine.  We might have a lot of the same species of bacteria inhabiting our bodies, but in different amounts.  Or you might have some species I don't have, and vice versa.

We now know that only 10% of our cells are human.  The other 90% are bacterial.  Since our species, and for that matter, all animal species, evolved in a bacterial world, we depended on our resident bacteria from the very start.  We actually can’t survive well without them  In fact, maybe we shouldn’t think of them as “resident.”  Maybe we should think of them as part of us!

         Vast quantities of bacteria live in our gut.  They break down food, like cellulose from plants, that we can’t break down ourselves.  They manufacture vitamins we need, like the B-group and vitamin K.  They regulate the amount of acid in our stomachs.

         Recently, researchers have begun to think some of our bacteria actually “teach” our immune systems how to function.  In particular, our bacteria may regulate our "killer T-cells," such as the one in the micro-photo I've posted today.

         How amazing: we may have evolved to need certain bacteria to regulate the immune systems we had come to think of as nearly supernatural in their ability to fight off infection. 

         How intriguing: this immune regulation may have something to do with rising rates of asthma.


We Are (Definitely) Not Alone

I’m always bedazzled when I realize that we live in a bacterial world.  Nothing shows quite so graphically the power of evolution.  Bacteria, especially “friendly,” useful bacteria, are the dark matter of our lives.  And we only become aware of them when they go missing and something goes wrong.

         I’ve mentioned before the strange business of increasing rates of asthma and other allergic conditions in present-day children.  Strangest of all is the fact that rural children, especially farm children, don’t seem to be affected.  Those kids don’t suffer from the over-sterilized city world of anti-bacterial soaps and cleaning solutions.  Apparently, when children are exposed to an enormous variety of bacteria from birth, they are protected from allergies to some degree.

         Recently, research has begun to show that our protective bacteria inhabit every part of us they can get to, and that we contain enormous numbers and kinds of bacteria.  These guys are being called a “microbiome,” and each of us has our own, different to some degree from everyone else’s. 

         We begin to pick up our own microbiome as we pass through our mothers’ birth canals.  (Children born by Caesarian section have higher asthma rates than those born vaginally!)  After birth, we continue to pick up bacteria from the air, from food, and all sorts of sources..  Every part of our bodies that is exposed to the outside becomes inhabited by an enormous variety of bacteria. 

         And it turns out we really need these bacteria for nutrition, for protection, for the proper functioning of our bodies.  All those anti-bacterial products we use to get rid of “germs” are making some of us sick, or obese, or who knows what else? 

         A good example of people trying  to re-do what the Cosmos has already done much better.  We need more humility.


With Asthma, Which Came First, Genes or Bacteria?

In my last three posts, I’ve been writing about the puzzling and intriguing association between the microbes in our bodies and asthma.  Research seems to show that the lungs and guts of children with asthma house different and less varied communities of bacteria, fungi, and viruses than non-asthmatic children. 

         Research also seems to show that very early exposure to a great variety of such microbes protects against asthma.  For instance, babies raised in rural areas or born vaginally, are far less likely to have asthma than babies born by caesarian section or raised in “clean,” disinfected urban environments.

         However, these connections are merely associations of one condition with another.  We don’t know if there is a cause and effect relationship.  Perhaps the children with asthma are genetically likely to have the disease, and the same genetic make-up also predisposes them to host specific microbial communities in their bodies.  Perhaps on the other hand, the children without asthma have different genes, that protect them from the disease and, at the same time, allow them to host different and more varied microbial communities.

         This is a special version of the quirky “nature or nurture” problem.  Nature or nurture is a human idea that probably has nothing to do with biological reality.  Many such questions turn out to have complex answers or no true answers at all. Unquestionably, the association of health or asthma with various internal communities of bacteria is complicated.  It is a research adventure full of wonder, worth following for some time to come.


Asthma: Good Bacteria & Bad Bacteria?

In my last two posts (Jan 4 & 7), I’ve been discussing the apparent connection between resident bacteria in our bodies and asthma.

         One of the most interesting findings about this comes from a study by William Cookson and Miriam Moffatt at Imperial College, London.  They found that asthmatics tend to have flu-type bacteria in their lungs, even though they may not be sick.  On the other hand, non-asthmatics’ lungs tend to contain soil bacteria, sea bacteria, and gut bacteria.

         The question is, what is the role of these bacteria?  Do they cause or protect against asthma?  Do they cause or protect against something which itself causes asthma?  Or is the connection something we haven’t thought of yet?

         This is going to be an interesting topic to follow for many years.  There are so many clues and so few answers. 

         I'll have some final thoughts on bacteria, asthma, and human beings in my next post.