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Nick Lane (2022) Transformer
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Solving the origin of life is showing that non-enzymatic chemical reactions
can create the basic chemicals of life. There can be no enzymes involved at
that phase because enzymes are proteins.
Proteins are highly specific non-random chains of hundreds of amino
acids. Such chains must be specified by a hereditary molecule such as DNA.
The translation of the information from DNA into a protein is a highly
complex process involving very large protein complexes called ribosomes.
Also required is the presence of a 'dictionary' that translates the
information in DNA into the amino acids of the protein. This is known as
the 'genetic code'. The point of DNA is 'producing' proteins. On its own
DNA is useless. All this machinery is too complex to be present at the
origin of life. So, the big challenge is to create a theory of the origin
of life without enzymes and DNA. Nick Lane knows all this. But
there is more: any living entity, any cell how simple it may be, requires
a reliable and suitable source of external energy. Furthermore, a
proto-cell needs suitable raw materials to create the core metabolism and
the cell boundary, a membrane. Nick Lane solves all this in his latest
book Transformer: The Deep Chemistry of Life and Death in an
admirable and impressive way. He describes a very plausible scenario: how
proto-cells can emerge, what chemicals and chemical reactions are
involved, and where the energy comes from. Indeed, an enzyme-free and
DNA-free origin of life. Specific inorganic catalysts are fulfilling the
role of enzymes.
Lane did not try to solve the origin of the genetic code in this book, but
people in his lab are working on it [1]. Anyway, it is the next step.
Needless to say his scenario is a 'metabolism-first' scenario. The
competitor, the 'replication-first' (or: 'genes first') scenario, fails
because the necessary building blocks have to be formed first. And that is
biochemistry. That is metabolism. Lane does more than explaining the
origin of proto-cells. He explains and shows in great detail (intimidating
for a non-biochemist!) how the universal core of metabolism of every
modern living entity is dictated by the physical-chemical environment
where life likely had originated ('The Deep Chemistry of Life'). Certainly
no small feat. Despite my complete lack of biochemical knowledge I was
deeply impressed.
And if that is not enough, for interested readers, he put forward his
thoughts about cancer and consciousness in biochemical terms. The book
itself is relatively short. The big surprise is the extensive annotated
literature list (60 pages) of all the books and articles that were crucial
for writing his book and his scientific thinking in general. It's a book
in a book. Far from being boring, I found it inspiring. It shows how he
learned from other great scientific minds. So, it are personal
recommendations. I found important papers I didn't know. Never was a
literature list so rewarding. I am going to reread and use it the coming
days and weeks as a resource for my own reading and writing.
Sources
Nick Lane (2022) Transformer: The Deep Chemistry of Life and Death:
"This book aims to show that the flow of energy and matter through cells
structures biological information rather than the other way around. ...
genes did not 'invent' metabolism, but the reverse."
Personal website Nick Lane
. I used the e-book version (KOBO). The book has been
reviewed
in Science 30 Jun 2022
The following sources are mine:
- Stuart Kauffman (1995)
At Home in the Universe. The Search for Laws of Self-Organization and
Complexity
(my review). When I first read Kauffman I was impressed but at the same time I was
puzzled and worried by the complete lack of DNA in his origin of life
scenarios: "There must be more to life than base pairing"
(Sorry for Watson & Crick!)
"Is there a way that an auto-catalytic set could evolve without
all the complications of a genome? ... In short there is reason to
believe that auto-catalytic sets can evolve without a genome." (p.
72-73 hardback).
The problem is: we live in the age of genomics.
Life is unthinkable without millions and billions of DNA bases in our
genomes.
Only later I recognized how important the omission of DNA was in any
origin of life scenario. We must forget all about DNA at the origin of
life. Conceptually, a difficult step initially, but crucial. Also, we must
forget about enzymes. Kauffman replaced enzymes with
auto-catalysis.
I still think that the DNA molecule is the greatest invention of the
universe ever. We wouldn't be here without DNA to talk about DNA.
Important: DNA is biochemistry too! There may be a non-DNA phase and a DNA
phase in the origin of life, but at all time it is biochemistry. At
universities genetics (studying genes) and biochemistry (studying
chemical processes) are separate disciplines. In nature there is no
distinction between biochemistry and genetics at all.
- Tibor Gánti (2003) The Principles of Life (my review). This book transformed my view of life: the definition and the origin
of life. I am still impressed by the clarity and logic of his model of
life. He was ahead of his time. Gánti (trained as a chemical engineer)
designed enzyme-free systems of life but included a hereditary system as
an essential subsystem. The other two subsystems are: a boundary
(membrane) and a motor subsystem (metabolism). "Gánti liberated himself
from the burden of the genetic code" says Szathmáry." Just like Nick Lane
[2]. The logic of
Gánti's enzyme-free system is that there must be a chemical system in the first
place. Only then it can be catalyzed and regulated by enzymes and genes.
Just like Nick Lane [2].
The editors of the 2003 reprint point out: "Gánti points to an interesting possibility: metabolism
might evolve without a genetic substance coding for it." (note on
p. 127). Gánti: "chemoton theory involves the assumption that the
fundamental characteristics of living systems do not depend on an
enzymatic regulation." (p.136).
About a genetic system: "Self-reproduction, and therefore inheritance in
the strict sense, can be achieved without an information-carrying
subsystem." (p.125). Please note that the original edition was first
published in Hungarian in 1971!
-
New origin of life model fatally requires a nonrandom protein, blog 24 December 2012. Nearly ten years ago a biologist had the
courage or foolishness to come up with a criticism of the work of two
high ranking biochemists. My complaint: "At any stage before the
dna-protein world, the presence of a non-random protein, no matter how
simple, is forbidden." That's exactly the issue that the current blog
emphasizes.
Notes
-
Nick Lane kindly informed me that in the mean time he and his coworkers
published a new theory about the origin of the genetic code:
A biophysical basis for the emergence of the genetic code in
protocells. [10 Sep 2022]: "the chemistry of the universal core of metabolism can indeed occur spontaneously in the absence of genes and enzymes." Nucleobases and amino acids can be produced non-enzymatically.
- Please note that Kauffman and Gánti did theoretical work. Kauffman is certainly a theoretical
biologist and Gánti was a theoretical biochemist contrary to Nick Lane who does theoretical and practical work. And it's all about experimental evidence! Without facts no theory can be tested! [11 Sep 2022]
