Old discoveries, new cheer

THE GOOD VIRUS: The Amazing Story and Forgotten Promise of the Phage  

Author: Tom Ireland

Publisher: W W Norton

Pages: 389

Price: $30

THE MASTER BUILDER: How the New Science of the Cell Is Rewriting the Story of Life 

Author: Alfonso Martinez Arias

Publisher: Basic Books

Pages: 341

Price: $32

In the 1910s, more than a decade before the discovery of penicillin, the microbiologist Felix d’Herelle was growing diarrhoea-inducing bacteria in his lab. A scientist of few credentials and uncertain birth — no one knows if he was French, Belgian or Canadian — d’Herelle hoped to start an epidemic of the runs among a plague of locusts in Mexico and thus kill them off.

While cultivating his deadly microbial soup, he noticed something strange. A mysterious entity had left holes in one of his thin films of bacteria. He took samples from within the holes, spread them on other plates of bacteria and got the same effect. More holes! The culprit, it would later turn out, was a phage, a kind of virus that “eats” bacteria.
 

While recent events have provided a painful reminder of the very bad viruses that prey on us, Tom Ireland’s The Good Virus is a colourful redemption story for the oft-neglected yet incredibly abundant phage, and its potential for quelling the existential threat of antibiotic resistance, which scientists estimate might cause up to 10 million deaths per year by 2050. Ireland, an award-winning science journalist, approaches the subject of his first book with curiosity and passion, delivering a deft narrative that is rich and approachable.
 

In the hands of d’Herelle and others, the phage became a potent tool against cholera. But, in the 1940s, when the discovery of the methods to produce penicillin at an industrial scale led to the “antibiotic era,” phage therapy came to be seen as quackery in Europe and America, in part, Ireland suggests, because antibiotics, unlike phages, fit the mould of capitalist society.

Capitalists love patents. A funny quirk of the patent system is that you cannot patent entire natural things, but you can sometimes patent the way you extract their by-products. Early microbiologists often harvested phages from one patient and gave them to another who was suffering from the same disease, but there was no easy way to separate the good virus from every other possible contaminant.
 

Phage therapy had a better reputation in the Soviet Union almost out of ideological spite, especially after superpower rivalries turned Western penicillin production methods into a Cold War secret. Ireland tells the fascinating story of how phages harvested from German corpses helped the Soviets defeat the Nazis when cholera broke out during the siege of Stalingrad.

Although phage therapy is still considered an option of last resort in most countries, including the United States, scientists have gotten better at purifying their phage cocktails and the fortunes of the phage have turned around.

Phages were also central players in the Western study of genetics during the 1940s and 1950s. Because phages seemed like relatively simple creatures, and they reproduced very quickly, they became a popular way for Cold War-era scientists to study heredity on a short time scale.
 

It wasn’t long before genomic sequencing technology stole the spotlight. The first full genome was sequenced in 1976. (It belonged to a phage.) By then, perhaps because of their downright scary appearance phages were overshadowed in the eyes of the American public by the “beautiful form” of the DNA double helix.
 

A similar PR problem confronts the protagonists of Alfonso Martinez Arias’s  The Master Builder. Here, the underdogs are cells. “Since the discovery of the structure of DNA,” Martinez Arias writes, “it’s become common to refer to DNA as the ‘book of life,’ a text made up of a sequence of letters — A’s, G’s, C’s and T’s — that serves as an instruction manual for building organisms. But what are the instructions for, and who carries them out?”
 

Martinez Arias, a developmental biologist, has lived and breathed the cell’s struggle to be heard over a career spanning 40-odd years. His story is one of DNA elites against hardworking, blue-collar cells. Cells, not DNA, Martinez Arias points out, determine the ripples of our fingerprints and the texture of our irises.
 

Martinez Arias builds his argument against the supremacy of DNA around Frankenstein-like experiments. Take, for instance, the fruit fly PAX6 gene. When this gene is mutated, flies develop without eyes. Yet when a human version of PAX6 is swapped in for the fly gene, it makes a fly with fly eyes, not a fly with human eyes.
 

This is because fly cells are doing the work. Living things are much more fluid, Martinez Arias argues, than the concept of a DNA instruction manual would have us believe. An organism is less like a car, built according to a precise blueprint, he suggests, than a hobbyist’s renovation project, where the cells who live there build a deck based on the tools that happen to be lying around in the garage and whatever lumber is on sale at the store. Many of the differences between you and me are the result of accidents in time, enacted by our cells.
 

Martinez Arias’s apparent goal, like Ireland’s, is to push aside Occam’s razor and free us from the inclination to accept simple answers. Sometimes the truth is the murky old news that’s been sitting right in front of us the whole time — undiluted, unsavoury and complex.


The reviewer studies phages at the Dana-Farber Cancer Institute in Boston ©2023 The New York Times News Service