A brief account on the study of the insulin crystal structure

Abstract

Approximately forty years ago when China was undergoing a period of great difficulty, Science in China, previously known as Scientia Sinica, published articles during three consecutive years (Scientia Sinica (test issue) 1972; Scientia Sinica 1973, No. 1, 93; Scientia Sinica 16(1973)136; Scientia Sinica 17(1974)51) on crystal structure analysis of the rhombohedral 2-zinc pork insulin molecule at resolutions of 4.0 A, 2.50 A and 1.80 A, respectively (Figures 1 and 2). These publications delivered rare information on scientific research from a China which, at the height of the Cultural Revolution, was otherwise closed to the outside world. The news made international impact because this was the first protein crystal structure solved in Asia and one of the few rare structures solved worldwide; it heralded the start of intensive biophysical research in China. Nobel Laureate Dorothy Hodgkin of Oxford University traveled to the Institute of Physics in 1972 to visit the Beijing Insulin Structure Research Group (Figure 3). There, she spent one week carrying out a detailed comparison of electron density maps from the Oxford and Beijing labs and met extensively with the Institute’s young Chinese scientists. Later, at the 9th International Conference of Crystallography in Kyoto, she told the story of her visit stating that, “standards there [were] as high as achieved elsewhere.” She further impressed international crystallographers with her comments in a “News and Views” article in Nature (Nature, 1975, 255: 103) that “the present Peking map at 1.80 A resolution is the most accurate map available of the insulin electron density defined by experimental, isomorphous phase angles... and may well remain so.” Additionally, Professor Watanabe, the famous Japanese crystallographer at Osaka University, wrote to the Institute in Beijing seeking permission to translate the 2.50 A article for publication in Japanese journals. Many other scientists of world famous laboratories also poured in to visit. Behind the articles published by Science in China lay a hidden story of dedication, courage and collective wisdom and expertise of intelligent young scientists who worked solidly and tirelessly over many difficult years (Figures 4 and 5). The year 2010 hails the 60th anniversary of this journal and seems to be an exceptionally appropriate opportunity for making a brief recollection of that experience, not only to pay tribute to all the members of the group but also to show gratitude to the journal.