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The end of nature’s mystery

Michael Barrett, a leading research scientist, spends his days stripping life down to its chemical c

In the beginning, God created the heaven and the earth. He then spent six days knocking together everything upon earth: millions of living species and even more now extinct ones. Yet it is not easy for biologists to believe in God the Creator; 50 years of extreme reductionism have removed much of nature’s mystery. We know all about the genetic code, and how the chemical composition of DNA can be translated into the panoply of proteins that shape cells and drive the chemical reactivity that defines each species. My job involves stripping tiny microscopic parasites down to their bare chemical components, which I compare to those of mammalian cells. I seek subtle differences that could allow us to construct molecules that interfere with parasite, but not human, chemistry. These experiments, we hope, will lead to the formulation of new drugs in our fight against disease.

Spending one’s time deconstructing life to its chemical components does, however, lead one to ask just what it is. If I took each and every chemical that comprises a cell and mixed them together, I would create nothing more than a chemical goo. There are, of course, organising principles that make life far more than the sum of its chemical parts. For some, an intelligent

designer could do this. Elsewhere, a relatively young discipline called systems biology aims to combine knowledge of the cellular chemical parts list with high-power computation to try to identify whether those organising principles themselves are no more than a mathematical consequence of self-assembled parts and time.

So far, for all our posturing, no one has come close to creating a living organism from a non-living, “abiotic” start. Craig Venter, famed for his profit-driven efforts to sequence the human genome, is making much fanfare about his attempts to “create” a new life form. In reality, however, all Venter is aiming to do is add a new, synthesised, genetic blueprint to a preorganised cellular system. This is an extreme version of the genetic engineering of microbes that has been going on for several decades now.

When Charles Darwin published On the Origin of Species in 1859, he conspicuously evaded an explanation of man’s position in the evolutionary tree. He also failed to touch on just how the whole thing got going. Naturally, he did have thoughts on the subject. “But if (and oh what a big if) we could conceive in some warm little pond, with all sorts of ammonia and phosphoric salts, light, heat, electricity, &c. present, that a proteine [sic] compound was chemically formed ready to undergo still more complex changes,” he wrote to his friend the botanist Joseph Hooker in 1871.

By the early 20th century the great British geneticist J B S Haldane had transmuted Darwin’s “warm little pond” into the so-called “primordial soup theory”, evoking a watery planet, warm and rich in gaseous chemicals such as ammonia, hydrogen, methane and carbon dioxide. In 1953, the American Stanley Miller tried to

re-create such a primordial soup in the laboratory. He set up a series of test tubes containing water, many of the proposed gases and a supply of electric sparks to mimic the lightning-charged atmosphere of early earth. Remarkably, those simple gases were easily converted into some of the basic organic chemicals typically found in living organisms. Miller’s success led to the hope that it would be only a matter of time before simple biochemicals could be turned into the more complex molecular strings characteristic of living cells today. But decades of ever more sophisticated experimentation have failed to yield significant advances.

Proponents of the “abiotic” origin of life point out that the four to five billion years of earth history is rather longer than the 56 years since Miller’s experiment. Some scientists believe that life could have evolved anywhere in the universe and then been carried on comets from solar system to solar system, from planet to planet. Such astrobiological origins would lead to a vastly increased probability that conditions suitable to spark life were met somewhere.

As a biochemist, I retain faith in the notion that life evolved through spontaneous chemical reactivity. One theory points to life emerging during the Hadean Aeon in the hot depths of the ocean. This era covers the first half-billion or so years of Planet Earth’s history, when volcanic matter was constantly spewing up through the ocean floor, heating water and causing an extraordinary mix of chemical constituents. The problem with this idea, however, is that the molecules forming in such conditions diffuse throughout the ocean, so diluting them to negligible levels.

The British geologist Mike Russell and Bill Martin, an American evolutionary biologist, adapted the so-called iron-sulphur world theory to try to lead us from simple chemical reactions to entities recognisable as living cells. Iron-sulphur complexes are among the best chemical catalysts that we know today, and iron and sulphur are abundant in volcanic exhalations. Many of the proteins (called enzymes) that catalyse the reactions of cellular life today use little iron-sulphur clusters, buried deep within their structures.

According to Russell and Martin, iron-sulphur deposits within tiny cavities in Hadean rocks (think, for example, of the holes in pumice stone – only smaller) could have catalysed the for­mation of a multitude of biochemicals. In the enclosed environment of those cavities, these chemicals could accumulate. Some molecules can actually catalyse their own production. Many evolutionary biologists today believe that some time after the first chemical burst, the emergence of so-called ribonucleic acids (RNAs) provided a huge expansion in self-replicating and, critically, mutating chemistry. Today, we know that RNA can fold in ways to drive its own assembly, and to catalyse the formation of other molecular configurations as well. Complex novel chemicals could emerge. Among these would be the structures we know as lipids, which are capable of forming self-sealing membrane bags. These lipid bounded bags could then free the chemical reaction chambers from their rocky confines. The first free living cells would be born. The processes of Darwinian evolution would then select those that were able to survive and replicate the best.

The individual steps of Russell and Martin’s theory are feasible. But did they happen? Obviously it is difficult to obtain definitive proof for events that occurred billions of years ago. So we have to accept that many of the steps in this, and other origin theories, as is often said, “could happen given enough time and the right conditions”. Divine interventionists can rightly argue that the abiotic, chemical view is no more proven than the existence of their omnipotent Creator.

The unrelenting deconstruction of life’s mysteries to their chemical bare bones, however, leaves me believing that we really are no more than a bag of chemicals; our oldest ancestors no more than a string of self-assembling molecular building blocks; our very consciousness nothing more than the output of a chemically driven series of electrical impulses, selected ultimately, perhaps, to ensure the propagation of a seminal chemical reaction.

Michael Barrett is professor of biochemical parasitology at the University of Glasgow

This article first appeared in the 06 April 2009 issue of the New Statesman, God special issue

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The New Times: Brexit, globalisation, the crisis in Labour and the future of the left

With essays by David Miliband, Paul Mason, John Harris, Lisa Nandy, Vince Cable and more.

Once again the “new times” are associated with the ascendancy of the right. The financial crash of 2007-2008 – and the Great Recession and sovereign debt crises that were a consequence of it – were meant to have marked the end of an era of runaway “turbocapitalism”. It never came close to happening. The crash was a crisis of capitalism but not the crisis of capitalism. As Lenin observed, there is “no such thing as an absolutely hopeless situation” for capitalism, and so we discovered again. Instead, the greatest burden of the period of fiscal retrenchment that followed the crash was carried by the poorest in society, those most directly affected by austerity, and this in turn has contributed to a deepening distrust of elites and a wider crisis of governance.

Where are we now and in which direction are we heading?

Some of the contributors to this special issue believe that we have reached the end of the “neoliberal” era. I am more sceptical. In any event, the end of neoliberalism, however you define it, will not lead to a social-democratic revival: it looks as if, in many Western countries, we are entering an age in which centre-left parties cannot form ruling majorities, having leaked support to nationalists, populists and more radical alternatives.

Certainly the British Labour Party, riven by a war between its parliamentary representatives and much of its membership, is in a critical condition. At the same time, Jeremy Corbyn’s leadership has inspired a remarkable re-engagement with left-wing politics, even as his party slumps in the polls. His own views may seem frozen in time, but hundreds of thousands of people, many of them young graduates, have responded to his anti-austerity rhetoric, his candour and his shambolic, unspun style.

The EU referendum, in which as much as one-third of Labour supporters voted for Brexit, exposed another chasm in Labour – this time between educated metropolitan liberals and the more socially conservative white working class on whose loyalty the party has long depended. This no longer looks like a viable election-winning coalition, especially after the collapse of Labour in Scotland and the concomitant rise of nationalism in England.

In Marxism Today’s “New Times” issue of October 1988, Stuart Hall wrote: “The left seems not just displaced by Thatcherism, but disabled, flattened, becalmed by the very prospect of change; afraid of rooting itself in ‘the new’ and unable to make the leap of imagination required to engage the future.” Something similar could be said of the left today as it confronts Brexit, the disunities within the United Kingdom, and, in Theresa May, a prime minister who has indicated that she might be prepared to break with the orthodoxies of the past three decades.

The Labour leadership contest between Corbyn and Owen Smith was largely an exercise in nostalgia, both candidates seeking to revive policies that defined an era of mass production and working-class solidarity when Labour was strong. On matters such as immigration, digital disruption, the new gig economy or the power of networks, they had little to say. They proposed a politics of opposition – against austerity, against grammar schools. But what were they for? Neither man seemed capable of embracing the “leading edge of change” or of making the imaginative leap necessary to engage the future.

So is there a politics of the left that will allow us to ride with the currents of these turbulent “new times” and thus shape rather than be flattened by them? Over the next 34 pages 18 writers, offering many perspectives, attempt to answer this and related questions as they analyse the forces shaping a world in which power is shifting to the East, wars rage unchecked in the Middle East, refugees drown en masse in the Mediterranean, technology is outstripping our capacity to understand it, and globalisation begins to fragment.

— Jason Cowley, Editor 

Tom Kibasi on what the left fails to see

Philip Collins on why it's time for Labour to end its crisis

John Harris on why Labour is losing its heartland

Lisa Nandy on how Labour has been halted and hollowed out

David Runciman on networks and the digital revolution

John Gray on why the right, not the left, has grasped the new times

Mariana Mazzucato on why it's time for progressives to rethink capitalism

Robert Ford on why the left must reckon with the anger of those left behind

Ros Wynne-Jones on the people who need a Labour government most

Gary Gerstle on Corbyn, Sanders and the populist surge

Nick Pearce on why the left is haunted by the ghosts of the 1930s

Paul Mason on why the left must be ready to cause a commotion

Neal Lawson on what the new, 21st-century left needs now

Charles Leadbeater explains why we are all existentialists now

John Bew mourns the lost left

Marc Stears on why democracy is a long, hard, slow business

Vince Cable on how a financial crisis empowered the right

David Miliband on why the left needs to move forward, not back

This article first appeared in the 22 September 2016 issue of the New Statesman, The New Times