Friday, October 16, 2015

Mis-reporting bacterial resistance

Too many popular science journalists badly mis-report the reasons why bacterial resistance to a brand new antibiotic can be widespread in even the remotest parts of the world only a few years later.

Microbial Capitalism

Their failure occurs because they see the microbial world as bloody in tooth and claw as their very own vision of the human world.

In this version of the facts, an individual bacteria randomly produces a new gene mutation that protects that individual from a new antibiotic when it arrives on the scene.

That individual bacteria selfishly retains the copyright cum patent on that valuable new gene and only its direct offspring get the new gene.

Those offspring survive and flourish while all around them trillions times trillions of other individual bacteria, bereft of the new gene, go down like flies (or bacteria) before the onslaughts of the new antibiotic.

In four years the offspring of that single individual bacteria have nearly totally replaced all the other bacteria in the world.

Law of the jungle 'take no prisoner' competition leads to Darwin's survival of the fittest.

In fact, it is nothing like that at all.

Often, while a antibiotic is new to us humans, its mechanism of death has been directed at bacteria, in some form or other, hundreds of millions of years before us.

A mutate gene did indeed quickly emerge to combat the antibiotic's mechanism but it was not kept as an exclusive patent for one individual bacteria's benefit only.

Instead it was quickly taken up, perhaps from the decaying parts of a dead bacteria with the mutant gene, by other bacteria, even other bacteria from species distant from that first unique bacteria.


The process is known as horizontal gene transfer or HGT.

In fairly short order, that mutant gene was put into a convenient cassette of antibiotic-combating genes and that cassette is passed around from species to species via HGT.

Soon, individuals from all manner of different species and different strains of bacteria have the mutant gene in their genome, but the cost of adding and holding this additional gene makes them reproduce at a slower rate than do bacteria carrying a smaller genome load.

But these few 'reproductive cripples' are tolerated rather than eugenically gassed as humans might wish to do, and in time prove very helpful indeed when the collective bacteria biofilm they live within encounters this new antibiotic.

Nevertheless whenever biofilms encounter a new antibiotic, they have a number of different methods to combat it.

One is the presence of persister bacteria (a variant of bacteria first discovered by Henry Dawson's team back in the early 1940s while researching natural penicillin).


The persisters lie low - metabolically speaking - as long as the course of antibiotics is conducted and then come back to life once the antibiotics are gone.

They are why we are instructed never to stop taking a course of antibiotics merely because we 'feel better'.

Another way to hold off the new antibiotic is via the already existing mutated gene, spread by HGT, but HGT now conducted at an accelerated 'crisis mode' speed.


And third method is indeed the traditional Neo-Darwinism explanation of the survival of the fittest.

Because, under direct assault by a strong new antibiotic, any metabolically active bacteria that hasn't yet received the mutant gene by HGT, do indeed die off en masse.

The persisters and those with the new gene, flourish.

I have greatly simplified the actual process, because most beings - humans as much as any other lifeform - carry a mixture of currently useful genes and currently useless genes.

Each individual seems to have a slightly different mix of genes.

This diversity comes in handy whenever a species encounters a new threat.

The great advantage for the bacteria is that any suddenly needed gene can quickly spread from one individual to any number of other bacteria, right across the breath of different bacteria species.

Copyright greed will doom us

Humans, by contrast, selfishly use patents, copyrights and trade secrets/state secrets to see that even members of their own species can't access life-saving knowledge for free.

That was the Dinosaurs' method basically - and remind me where are they today ?

The microbes' far more inclusive form of genetics is why these tiny weak beings have lasted four billion years ---- and the dinosaurs didn't.

We have a choice, humanity : dinosaurs or bacteria....

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