A discussion of a hypothetical 50-bit self-replicating molecule as the basis for for life.

Personally, I have trouble seeing how anything that tiny can be useful: even in computers — which provide an optimal, intelligently-designed medium for perfect replication — 50 bits at most gets you a simple replicator (in the game of "Life", which must also be programmed by an intelligent agent) — one which is not even slightly resistant to errors.

"bornagain77", in the comments, describing the procedure for creating a very tiny (50 bits or so) strand of RNA. Sorry to quote so extensively, but it gives one a sense of the care which must be taken:

RNA was synthesized by Dharmacon. GUGGC = 5'-GUGGC-30 ; GCCU - 5'P-GCCU-3' ; 5'OH-GCCU = 5'-GCCU-3' ; GCCU20dU = 5'-GCC-2'-dU; GCC = 5'-GCC-3' ; dGdCdCrU = 5'-dGdCdCU-3' . RNA GCC3'dU was prepared by first synthesizing 5'-O-(4,4'- Dimethoxytrityl)3'-deoxyuridine as follows: 3'-deoxyuridine (MP Biomedicals; 991 mg, 0.434 mmol) was dissolved in 5 mL anhydrous pyridine and pyridine was then removed under vacuum while stirring. Solid was then redissolved in 2 mL pyridine. Dimethoxytrityl chloride (170 mg, 0.499 mmol) was dissolved in 12 mL pyridine and slowly added to 3'-deoxyuridine solution. Solution was stirred at room temperature for 4 h. All solutions were sequestered from exposure to air throughout.

Reaction was then quenched by addition of 5 mL methanol, and solvent was removed by rotary evaporation. Remaining solvent evaporated overnight in a vacuum chamber. Product was then dissolved in 1 mL acetonitrile and purified through a silica column (acetonitrile elution). Final product fractions (confirmed through TLC, 1.1 hexane:acetonitrile) were pooled and rotary evaporated. Yield was 71%. Dimethoxytrityl-protected 30dU was then sent to Dharmacon for immobilization of 30-dU on glass and synthesis of 5'-GCC-3'-dU.

PheAMP, PheUMP, and MetAMP were synthesized by the method of Berg (25) with modifications and purification as described in ref. 6. Yield was as follows: PheAMP 85%, PheUMP 67%, and MetAMP 36%.

Even more purification and isolation steps under controlled conditions, using multiple solvents at various temperatures, were needed to prevent cross-reactions. (and the understatement of the year) It is doubtful such complex lab procedures have analogues in nature.

The "rebuttal"? D. Mullinex (who has a wonderful name, IMO):

Of course, plate tectonics were at work even then, dragging millions of tons of sea water under the earth where it then percolated up through geologically active rock formations under conditions of high temperatures and pressure, which greatly speed up all chemical reactions.

The rocks the water was percolating through provided thousands of different chemicals for the hot water to dissolve and they also provided millions or billions of square kilometers of submicroscopic nooks and crannies to act as catalysts as the hot, chemically laden water flowed by.

Temperatures also rose and fell sharply as the water percolated past lava channels and then through cooler rocks.

That's a lot like a lab except that this natural lab is literally the size of all the continents on ancient earth, down to a depth of several kilometers.

Why yes, they're exactly equivalent. Any fool can see that.

Words fail.

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