Friday, November 30, 2012

A philosopher could have brought us life-saving penicillin years earlier than ten thousand chemists did

The claim that the only solution to penicillin's tiny yield, instability and impurities was to synthesize it sounded so good back in the 1930s and early 1940s - to scientists.

But perhaps not so good to philosophers .

But unfortunately philosophers were not asked to help out and did not thrust themselves forward.

So while millions died needlessly around the world between 1935 and 1945, professional philosophers - damn their eyes ! - just talked to other philosophers.

To paraphrase Michael Bliss, 'enough blame for all' : for both the chemistry-besotted scientists and the navel gazing philosophers.

To synthesize penicillin or any biological molecule in the 1930s and 1940s meant first separating it totally from its related impurities.

Now, by crystallizing it into pure 100% crystals, it was possible to begin to break those pure crystals of penicillin into its smaller subunits of linked atoms and begin the usually easy synthesizing of those subunits.

Finally, the real complicated art was to assembly all those subunits in the right shape so the molecule would have still have antibacterial qualities.

Knowing the correct letters and the correct number of each letter is just a start in building an unknown paragraph.

Now imagine having to create a three dimensional paragraph that makes sense - different sense, but sense - when read with its interconnected sentences sprayed in all four directions !

That' s what a biological molecule is : a slightly flexible piece of  recently chewed gum, with its active site (all of its value) in a tiny crease somewhere in the chewed inner edge of the piece of gum .

Wiggle (via chemistry) the gum a bit one way : useless ; a little in another way, a precious life-saver.

Your only aid is that chemistry is like a language and in any language, some letters are more common than others and more likely to go into certain letter orders than others --- just as words and sentences tend to follow others more or less predictably.

But chemistry syntax is as loosey-goosey as any real live language tends to be : lots left for slow trial and error.

We have been patiently trying to make quinine better and cheaper than Nature does for over 200 years - and chemists, even today, still can't do it : this Everest of chemistry remains unconquered though every serious chemist gives it a crack.

That was the second mistake penicillin chemists made : ignoring quinine's centuries of chemists' failures for more recent easy chemists' successes making other biological molecules.

The first mistake though was more in the realm of first year university logic.

Picture a handful of future Nobel prize winning chemists forced to squeeze behind an undergraduate's desk and explain to a philosopher of logic just why they were proposing to synthesize penicillin rather than simply, farmer-like, upping its biological yield.

To crystallize penicillin, the chemists patiently explain,  we need grams and grams of penicillin molecules, in very stable condition, and totally free of the closely related impurities that now irritate the patient getting the injection.

Right now, we are just getting 1 part pure penicillin to 1 million parts rubbish ( ie 1 microgram of actual penicillin , mixed in with 99.99% rubbish) per gram of 'natural'
 penicillin, and its very unstable.

So, says the philosopher slowly, like a spider to a fly, you hope to succeed in gets lots of pure stable  natural penicillin ---congratulations !

But why then bother with the difficult task of synthesizing it - haven't you already succeeded in your employers' real end goal ?

God knows, even senior chemists might begin to sense the logic in that proposal.....

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