Double Helix: How an Image Sparked the Discovery of the Secret of Life
Chapter One GLIMPSE OF A PHOTO James Watson carried a document with him on the 50-mile 80-kilometer train trip from Cavendish Laboratory in Cambridge England to London The paper had already traveled more than 5,000 miles 8,047 km from California before arriving in his hands that late January day in 1953 He could not wait to share the news it held The American biologist hurried along the wide courtyard of King’s College in London where a German bomb had destroyed underground labs just over a decade earlier World War II had demanded the skills of many scientists including those of Maurice Wilkins the friend he was heading to see in the King’s College physics labs Wilkins had worked to improve radar then traveled to Berkeley California to help develop the first nuclear weapons But by the end of the war he felt very disgusted with the dropping of two bombs on civilian centers in Japan 1 and returned to England and to King’s College to study something new After earning undergraduate and graduate degrees in the United States James Watson worked with scientists in England Inside the physics labs Wilkins peered into cells deep inside the nucleus to a molecule called deoxyribonucleic acid DNA for short No one fully understood the shape or construction of the molecule Many other scientists were more interested in studying the cell’s proteins After all they are complex and direct nearly every task in the human body Yet some scientists including Wilkins hoped that finding the simple
structure of the DNA molecule would help answer a great mystery of life How do organisms live grow develop and survive generation after generation Watson thought the answer might lie in DNA Questions about the mysterious molecule had brought him across the Atlantic Ocean to labs in Europe three years earlier It was well known that DNA was composed of a few basic parts phosphate and sugar molecules that were linked to form chains Scientists also knew that DNA contained four types of nitrogen-based molecules called bases adenine cytosine guanine and thymine But how did these simple building blocks all fit together King George IV and the Duke of Wellington founded King’s College London in 1829 It is part of the University of London Watson burst into King’s physics labs eager to share a new scientific paper written by Linus Pauling of the California Institute of Technology It described how these simple parts could build a DNA molecule Twenty-four-year old Watson admired Pauling the 51-year-old chemist who had discovered that protein molecules could take the shape of a coil called an alpha helix In a 1950 lecture Pauling had presented his model of the single staircase-like structure and received worldwide praise There was
no one like Linus in all the world Watson once wrote The combination of his prodigious mind and infectious grin was unbeatable 2 Linus Pauling would win two Nobel prizes one in chemistry and one for his work for peace But the famed chemist had blundered with DNA and Watson knew it Pauling’s mistake was contained in a diagram in the paper Watson clutched Pauling imagined a triple helix of phosphate and sugar chains twisting around each other with the nitrogen bases attached and pointing outward like leaves on a tree branch Watson knew this theory was wrong because he had made an inaccurate triple helix model himself a year earlier On his way to find Wilkins Watson stopped by the office of another scientist Rosalind Franklin X-ray photographs and books were spread across her desk She was also deep into studying DNA’s structure but she was not interested in Pauling’s diagram She distrusted the celebrated scientist’s method He had discovered the alpha
