On his fiftieth birthday, Feb. 28, 1951, Pauling mailed a manuscript, "The Structure
of Proteins: Two Hydrogen-Bonded Helical Configurations of the Polypeptide Chain"
to the Proceedings of the National Academy of Sciences (PNAS) It was the expanded version of the note he and Corey had published four months
earlier, this time adding Herman Branson's name. It was a detailed description of
the alpha and gamma helixes.
A few days later, Pauling wrote Weaver, "The difference between our two predicted
configurations and others that have been described in the literature is that ours
are precise, whereas the others are more or less vague." This much was true. But Pauling's
next statement – "I feel in a sense that this represents the solution of the problem
of the structure of proteins." – would prove wildly inaccurate. Weaver, for his part,
saw the paper as a justification of his years of support for Pauling's protein research.
He dispatched a science writer and publicist named George Gray to Pasadena to prepare
a full report for the Rockefeller trustees.
Pauling also gave a heads-up to the editor of a popular science magazine, Scientific American, pushing for publicity even before his paper appeared in print, writing, "It seems
to me to be just about the most important step forward that has been made during the
last 25 years or perhaps 50 years in this field." The editor quickly replied, asking
for more details about Pauling's "bombshell," and asking him to write an article about
it for the magazine.
By then, however, Pauling was deeply engrossed in more protein work. It was as though
sending in the paper on the helixes freed him to finalize his other ideas. Through
March and into April, he and Corey feverishly finalized their ideas for a half-dozen
more protein structures. "I am having a hard time keeping my feet on the ground now,"
he wrote a former student in mid-March. "I have been working night and day, neglecting
almost everything else."
On April 1, the Pauling, Corey, and Branson paper on the alpha and gamma helixes was
published in PNAS. It proved a turning point in the history of molecular biology. Upon reading it,
Sir Lawrence Bragg rushed to the nearby laboratory of Alexander Todd, an expert in organic chemistry, to ask if indeed the peptide bond was planar, as
Pauling insisted. "I told him," remembered Todd, "if he had asked me at any time in
the past ten years, or if he had asked anybody in my lab, we could have told him that
the peptide bond had to be planar." If the peptide bond was planar, Bragg realized,
there was a very good chance that Pauling's alpha helix was right. Bragg was a physicist.
He now saw that he had lost a race because he had overlooked some facts of chemistry.
Todd said Bragg was "horrified" when he heard the news, and swore from that point
on never to allow anything to be published by his protein group again until they got
Todd's okay on the chemistry of their structures.