Friday, June 12, 2015

When a scientific consensus was proven wrong : DNA and Penicillium

Dr Martin Henry Dawson was widely considered a minor medical researcher, all because he had bet on two clearly losing horses.

In 2020, it might no longer be seen that way.

In the first case back in between the wars, the general scientific consensus was that large proteins had to be complicated and hence 'smart' and long chains of mere repeating acids had to be simple and hence 'stupid'.

So when Dawson's pioneering 1920s test tube research on the ability of some bacteria to take up the genes of other species (today known as HGT) led to one of these long simple repeating chains rather than to a protein, the scientific jungle telegraph dot dashed out a signal : "Dawson --- dead wrong, dead end !"

But of course, the telegraph signal is itself nothing but long chains of very simple repeating sub units, a mere dot and a dash, yet it has no problem transmitting the most complicated examples of human reasoning perfectly accurately.

And so to with the simple-appearing DNA .

For as it turns out, it (the tortoise not the hare) was the actual brains behind genetics, while the complicated protein was merely a (highly useful) spindle for the coil of DNA.

Bacteria, it seems, can smoothly nip and tuck DNA bits and bobs ( genes basically) and we humans still can't.

Oh, we appear to, but actually we let the bacteria take all the hard work while we take all the credit.

Round One, ultimately, to Dr Dawson.

Kitchen Mold

During WWII, many scientists again thought Dawson had backed the wrong horse.

They felt that he had chosen, in effect, to endanger dying patients by delivering Vitamin C via old fashioned crude un-purified natural orange juice rather than via modern, progressive pure synthetic Vitamin C pills.

For in 1940, the scientific consensus was that German chemists were very very brilliant and the tiny microbes were very very stupid.

Dawson thought that if supposedly simple bacteria could do excellent gene engineering while Man could only fumble about, maybe other microbes might also be better at certain types of chemistry than even the smartest chemists in the universe.

So Dawson bet that the humble penicillium mold might just do the job of making massive amounts of (admittedly impure but totally safe) penicillin better and cheaper (and certainly quicker) than all that human chemists had produced, after a fifteen years of fruitless trying.

Dawson (along with his fellow believers at Pfizer and the OPRD) were proven spectacularly right and the synthetic-obsessed Nobel Prize winning pair of Alexander Fleming and Howard Florey (along with Merck and Vannevar Bush's feckless OSRD) were proven wrong, wrong, wrong.

We humans - 75 years later - still can't make economical Penicillin G by total synthesis and the little bugs still make it by the tens of thousands of tons, which we then modify to produce most of the antibiotics we use today.

And the wartime efforts of German chemists were even worse when it came to making penicillin (their wartime successes were mostly limited to producing the Zyklon B gas used in the Holocaust.)

If the doubly right Dawson remains unknown today, it is hardly surprising, because a scientist rarely wins fame by bucking a worldwide scientific consensus of their elders.

Now I fully believe the burning of fossil fuels is causing a highly dangerous greenhouse gas effect in our atmosphere -and my view is also the consensus of scientists worldwide.

But I hope that I am still historically-minded enough to recall that many similar scientific consensus in the past have proven to be totally wrong.

Totally, totally, totally wrong ....

No comments:

Post a Comment