In Berlin and Beijing, Neufeld and Reimann had also moved on. The phenomenon of pneumococcal transformation could easily have died before its second birthday, but for a headstrong young man in New York. He had been intrigued by Griffith’s paper and wanted to repeat the experiments – but, strangely, his boss had told him not to. Then the boss went off on prolonged sick leave, and as soon as his back was turned, the young man seized his opportunity.
* Neufeld was unimpressed and preferred another of Shaw’s plays, Saint Joan.
12
TRANSFORMATIONAL RESEARCH
It was said later of Fred Griffith that ‘his kind will not be found, in this country or overseas’. In fact, several of Griffith’s boxes could have been ticked by the man who eventually picked up the research he abandoned and, after a couple of false starts, dragged it into a future that Griffith would never have believed. Both men were born in the same year (1877); trained to be doctors but quickly dropped patients in favour of bacteria; hated scientific conferences; and were lifelong bachelors with a favourite niece.
There was, however, a crucial difference between them. Unlike Fred Griffith, who had to squeeze in experiments around his routine service work, the other man ran a successful research group in a world-class institution and was free to indulge all his research fantasies. Meet Dr Oswald T. Avery, of the Rockefeller Institute for Medical Research in New York.
Professorial material
Oswald Avery was born in Halifax, Nova Scotia, where his father was an English Baptist preacher. When Oswald was ten, the Reverend Avery reassigned himself to the Bowery, the notorious skid row district of New York. At first, life there was good; Oswald and his big brother Ernest used to summon the faithful to the Mariners’ Temple with their cornets, and their upwardly mobile parents rubbed shoulders with the Rockefellers and other ‘scions of America’s saponaceous aristocracy’. Then everything turned sour. Ernest and his father both died from tuberculosis, leaving sixteen-year-old Oswald and his mother to bring up his younger brother Roy.
After school, Avery went first to theological college (where they noted that his ‘faith in Providence was second only to his faith in himself’) and then Columbia University Medical School. He graduated in 1904 but practised as a doctor for only three years, later confessing that medicine provided ‘many amusing stories’ but that his patients’ problems left him cold. His conversion to bacteriology came in 1906, on hearing Sir Almroth Wright lecturing, and he joined a private research lab to work on the bacteria in Bulgarian yoghurt which were supposed to confer longevity. Luckily, his talents were spotted by Rufus Cole, the Director of the Rockefeller Institute Hospital.
On 1 September 1913, aged thirty-six, Avery began a research career at the Rockefeller that would span both world wars. His mission was the same as Cole’s – to defeat the pneumococcus, and he focused on its immunology. Avery’s research emporium was on the sixth floor of the Rockefeller Institute Hospital, in an area originally designed as a ward. His personal laboratory lay beyond the busy main lab: a small, dimly lit room, entered at both ends through wooden swing doors with circular glass portholes (relics of the ward kitchen). Inside were a laboratory bench and a roll-topped desk with the front locked down to conceal piles of letters, mostly unanswered. The bench carried the tools of the bacteriologist’s trade: a brass microscope; racks of test tubes and boxes of glass microscope slides; bottles of reagents; loops of platinum wire set in wooden handles, for picking colonies of bacteria off culture plates; and a Bunsen burner with a hissing blue flame. The fine view across the Rockefeller campus was blocked by a permanently lowered blind, because the lamp that hung low over the bench worked better than sunshine.
Descriptions of the man who inhabited this twilit cavern have Tolkienesque overtones. Avery was short (just over five feet) and slightly built, with ‘large brilliant eyes’ and a ‘brooding forehead that appeared too heavy for the frail body’ (Figure 12.1). His public image was of an affable, well-dressed man with pince-nez glasses, who radiated charm and welcomed visitors with a broad grin. The students who enjoyed his graphic lectures about infections (‘If your saliva were blue, your patients would be living in a blue smog’) nicknamed him ‘The Professor’, generally abbreviated to ‘Fess’. A snapshot taken at an Avery Lab Christmas party shows ‘Fess’ as the life and soul, resplendent in a festive gown, a Fred Astaire-style top hat and a come-on-in smile.
At his laboratory bench, Avery was a different man: withdrawn, uncommunicative, and totally absorbed in the unforgiving rituals of microbiology. He handled all samples ‘as though they were the plague bacillus’; one tiny slip of his hand, and the entire experiment was consigned to the bin and restarted from scratch. When later experiments required ‘rather large quantities’ of a sludge of virulent pneumococci to be scraped by hand out of an industrial centrifuge, Avery always disappeared – not because he feared pneumonia, but because he could not bear to watch such appalling breaches of good laboratory practice.
Figure 12.1 Oswald Avery.
Almost everyone fell under the spell of ‘the most stimulating and gracious person on campus’. But beneath the veneer of charm, ‘Fess’ was – like Fred Griffith – a private man, prone to frequent ‘periods of dejection’ during which he tended to ‘dramatise his low spirits’. When sitting alone in his lab, he could often be heard whistling the tune that Wagner wrote for a depressed shepherd in Tristan and Isolde. On being telephoned with an invitation to give a guest lecture, Avery would trot out either ‘joyful acceptance or profuse regrets’ with his habitual charm – but after hanging up, the ‘smiling mask’ would drop to reveal ‘an almost tortured expression’.
Avery was a confirmed bachelor whose best friend was his younger brother Roy, later Professor of Microbiology in Nashville. Avery wrote to him frequently, and every summer enjoyed several weeks of ‘reflection and regeneration’ on Deer Isle, off the coast of Maine, with Roy, his wife and daughter (Avery’s favourite niece, who called him ‘Uncle Fess’). At work, Avery was closest to Alphonse Dochez, who had made his name with the ‘American scrapheap’ of Group IV pneumococci. Dochez, who was five years younger, moved into Avery’s large flat on 67th Street, which they shared for twenty-eight years until Avery retired and left New York.
‘Fess’ and ‘Doh’ made an odd couple. Avery rarely ventured out after work, while Dochez was a suave Belgian-American with a French accent that made American women go weak at the knees, and a socialite who ‘seemed to spend a good deal of time at the opera’. They were also a superb scientific partnership, constantly bouncing ideas off each other, at work and at home, day and night. In a typical scene, we find Avery tucked up in his pyjamas, with Dochez perched on the edge of the bed in full evening dress. They chatter non-stop until the small hours, picking through the ideas that had come to Dochez while Violetta was dying of tuberculosis in La Traviata.
Like minds
Soon after Avery started at the Rockefeller in 1913, he and Dochez joined forces to hunt down the antigens which identified each type of pneumococcus and were the target for the antibodies that killed them. They began by smashing up Type III pneumococci, adding specific antibodies to the debris and trying to extract whatever had stuck to the antibodies. After many months, punctuated by Avery’s moans of ‘Disappointment is my daily bread’, they isolated a nondescript greyish powder which readily dissolved in water. They named it the Type III ‘soluble specific substance’ (SSS); in time, they also found the SSSs for Type I and Type II pneumococci.
These were remarkable substances. Each SSS gave the pneumococcus its virulence as well as its immune identity; mice and rabbits injected with lethal doses of one type of pneumococcus could be saved by giving them antibodies against the appropriate SSS. The SSSs were easily detected in the blood and urine of patients on the pneumonia ward – hence a clever new diagnostic test that was cheaper and quicker than culturing the bacteria. (One of Avery’s moments of disappointment came when urine from their first patient failed to reveal t
he expected SSS. Then they checked the patient’s name on the sample, repeated the test with urine from the correct patient, and obtained the positive result.)
The SSSs were also iconoclastic. Until then, every antigen identified had been a protein – but the Type III SSS appeared to be a carbohydrate. Avery sought expert advice from Michael Heidelberger, a chemist working at the Rockefeller on haemoglobin. Heidelberger was busy, so Avery would ambush him in the corridor, brandishing a vial of SSS and demanding, ‘When are you going to work on it?’ When Heidelberger eventually yielded, he confirmed that the pneumococcal SSSs were indeed complex carbohydrates that consisted of simple sugars, linked together in long chains. He proved the point by making artificial SSS molecules from simple sugars off the laboratory shelf. These synthetic SSSs were the real thing; antibodies made against them could save the lives of animals that had been injected with virulent pneumococci of the same type.
Dochez’s interest eventually drifted elsewhere, but Avery remained faithful to the pneumococcus. He built up a large and busy group, using unconventional means to attract fresh talent. A new recruit was never told what he would work on. Instead, he would be cornered by Avery and subjected to a monologue about the pneumococcus and its unanswered questions. These recitals were highly polished and spiced with ‘humour, mimicry and verbal pyrotechnics’; they were known as the ‘Red Seal Records’ (after a popular gramophone label), because once Avery had started, he would continue without interruption to the end. The dazed recipient was then left to digest it all until he was ready to bring back a proposal for his own research.
Avery’s strategy worked brilliantly. For thirty-five years, this charismatic leprechaun of a man pulled in a string of bright young minds and, with few exceptions, nurtured each of them with the right mixture of intellectual freedom and fatherly support. The result was widely seen as some of the best bacteriological research on the planet.
On the sly
Like Fred Neufeld, Avery would have slept better if Fred Griffith’s ‘bombshell’ paper in early 1928 could be proved wrong. All his research over the last fifteen years, and all his plans for the future, were based on the assumption that the type was permanently engraved on each pneumococcus. Avery could not believe that pneumococci could change type, and suspected that some live S pneumococci had sneaked past Griffith’s heat treatment. It would have taken him no time to confirm or shoot down the notion of ‘pneumococcal transformation’, but his reaction was bizarre. He refused to repeat Griffith’s experiments, and vetoed any attempt by his team to follow up the lead. It was as though he was afraid of what they might discover.
This was out of character, but ‘Fess’ had not been well for months. He had lost weight, become badly depressed and had been forced to give up bench work because his hands shook. Luckily, this added up to the benign diagnosis of an overactive thyroid but the only treatment was a major operation to cut out the thyroid gland – and being a hypochondriac did not help. In spring 1928, Avery went on sick leave for a few months, leaving his research group rudderless. Most were happy to continue on their current course, but one restless young man saw the chance to make something memorable of his last few months at the Rockefeller.
Martin Dawson was another Nova Scotian, born twenty years after Avery, and a medical graduate of McGill University, Montreal. He became interested in bacteriology and in 1926, aged thirty, won a prestigious Canadian National Research Scholarship to work with Avery. The project which grew out of his Red Seal induction was to follow up the claim published by the then-harmless Fred Griffith that R and S strains of a single type of pneumococcus could interconvert. Dawson used a clever technique invented by Avery – growing cultures from a single pneumococcus, picked off a microscope slide – to exclude contamination with the other form, and confirmed Griffith’s finding.
He wrote the paper over Christmas 1927 and it was accepted by the Journal of Experimental Medicine early in the New Year. Unfortunately, it had lost all excitement when it came out (on April Fool’s Day 1928), because by then Griffith had published his claim that pneumococcal types – not just R and S forms of a single type – were interconvertible. And it must be true, because Fred Neufeld had just confirmed the finding. Dawson’s frustration deepened when Avery barred him from investigating Griffith’s finding.
The temptation of the forbidden fruit proved irresistible as soon as Avery went on sick leave. Dawson worked furiously against the clock to check Griffith’s experiments; luckily, Avery stayed away for over a year. In that time, Dawson went through hundreds of mice and hundreds of litres of pneumococcal culture. Using Avery’s single-bacterium culture method, he ‘completely confirmed’ Griffith’s findings that heat-killed S of a given type could transform live R of the same or another type into live, lethal S of the first type, when injected together into mice. He also found that transformation did not occur if the dead S had been heated to 100 °C. What was the ‘precise factor’ in the dead S that made transformation happen? No idea. It could not be the capsular SSS (which survived undamaged at 100 °C) but did not ‘correspond to any known substance or property of S pneumococci’.
As 1929 came to its end, Avery was still on sick leave and Dawson’s money had run out. Dawson moved across town to Columbia University – taking with him Richard Sia, a talented young doctor from Peking who had won a scholarship to work with Avery. There was no reaction from Avery, even when Dawson’s two papers were published in the January 1930 issue of the Journal of Experimental Medicine.
Over in Columbia, Dawson and Sia continued to pick away at the mysteries of pneumococcal transformation, and eventually made an important breakthrough: transforming pneumococci in the test tube rather than in living mice. It took them a year to perfect the recipe – a dash of blood broth (perhaps added in desperation), mixed in with dead S Type III and live R Type II. The reaction produced ‘typical III S colonies’, and the transformation was permanent and transmitted ‘apparently indefinitely’ to successive generations.
In April 1931, Dawson and Sia went to Montreal to present their findings to the Federation of American Societies for Experimental Biology. This meant that a monumental scientific milestone – the first successful transfer of genetic material into living organisms in the proverbial test tube – was reported in a 400-word abstract by M.H. Dawson and R.P.H. Sia, entitled ‘The transformation of pneumococcal types in vitro’.
In his regular reports for 1931-2, Avery made no reference to the abstract or the two papers in the Journal of Experimental Medicine by Dawson and Sia, on ‘In vitro transformation of pneumococcal type’. By now, both authors had moved on; Richard Sia had returned to Peking and Martin Dawson had discovered that his real interest lay in finding a cure for arthritis.
But back at the Rockefeller, another bright young thing had picked up where they had left off – and had already done extraordinary things with the ‘precise factor’ that caused transformation of pneumococcal type.
Rehabilitation
Lionel Alloway joined Avery’s lab for a two-year secondment in early 1930, a few months after Dawson’s departure. He was short and smartly dressed; despite his rakish bow tie, he looked terribly young to be a doctor. Still shaky with untreated thyrotoxicosis, Avery came in to fire the new boy’s imagination with a Red Seal recital. When Alloway announced that he wanted to investigate pneumococcal transformation, Avery let him do it; by now, he had grudgingly accepted that Fred Griffith was right.
Alloway’s youthful appearance belied a ferocious work ethic. His first paper had already been accepted by J Exp Med when Dawson and Sia’s were published; his second followed close behind. He had found a better way of killing the transforming pneumococci – dissolving them in bile salts – which also increased the yield of what he christened the ‘transforming principle’.
These powerful extracts enabled him to get closer to the mystery of what the ‘transforming principle’ might be. Alloway purified the unknown substance by forcing it through a cylindrical ceramic fi
lter with pores so fine that it held back bacteria; the water-clear fluid that passed through the filter was just as potent as the crude extract in transforming pneumococci. And something astonishing happened when he added ice-cold alcohol (a standard trick for isolating organic compounds). The liquid became syrupy and hard to stir, and a thick, heavy precipitate appeared. The precipitate could be collected, redissolved in salt solution and precipitated again with alcohol – and this cycle could be repeated many times without the precipitate losing its magical power to transform pneumococci. Here, at last, was the transforming principle in all its baffling glory. But what was it?
A matter of principle
Lionel Alloway was another bird of passage and had already flown the nest when his second paper came out in February 1933. After that, all went quiet with the ‘transforming principle’ for a couple of years, mainly because Avery’s illness – worsening symptoms, then the long-delayed operation and a stormy convalescence – kept him off work until autumn 1934.
Even while on sick leave, Avery’s passion for the pneumococcus was undimmed, as was his ability to dream up brilliant new experiments. Thanks to the efforts of his colleagues, pneumococcal research at the Rockefeller barely lost momentum while the chief was out of action. Avery’s lab was world-famous for its many and varied offensives against the pneumococcus, and the speed with which it attacked ‘the chemical problems of immunology from so many angles by so many workers’. Particularly exciting at this time was an enzyme (derived from a bacterium found in a peatbog where cranberries were grown) which broke down the Type III SSS. Tiny doses of the enzyme had saved the lives of monkeys with ‘fatal pneumonia’ that closely mimicked the human disease. The effect was so awe-inspiring that a junior member of Avery’s team had to be restrained from trying it out on patients in the pneumonia ward.
Unravelling the Double Helix Page 17
