Year: 2019
Type: article
Abstract: passed away on 10 January 2019, aged 98 years.She was an X-ray crystallographer who played an active role in the determination, with Dorothy Hodgkin in 1949, of the previously contested chemical formula of the important antibiotic penicillin.She then went to Caltech and worked in the laboratory of the X-ray crystallographers Linus Pauling and Robert Corey.There, in 1952, she reported her discovery of an additional manner of polypeptide folding in proteins to that of the -helix; she named it the '-helix'.Since that time she was an Assistant Professor of Physical Chemistry at Harvard University in Boston where she was among the first to introduce X-ray diffraction studies of crystalline proteins into laboratories in the United States.Then, in 1956, she moved to Columbia University of Physicians and Surgeons in New York where she continued studies of protein structure, becoming a full Professor in 1966.She remained there until her retirement in 1990.A much admired teacher and mentor, she continued to lecture there for most of the rest of her life.Barbara was born in Lancaster, England on 23 March 1920.She was a bright student, interested in science, and studied chemistry at Somerville College, Oxford University, with Dorothy Crowfoot Hodgkin as her tutor and mentor.Barbara obtained a BA degree in chemistry in 1946 and stayed on for graduate research in Dorothy Hodgkin's laboratory, obtaining a DPhil degree from Oxford University in 1948.Barbara did her undergraduate and graduate experimental studies with Dorothy Hodgkin on penicillin.The antibiotic activity of penicillin had originally been discovered by Alexander Fleming in 1928, and was being studied extensively in England and the United States.It had been first used on patients in 1943 and had served well in eliminating infections in many patients.In Oxford, penicillin research was led by Howard Florey, Norman Heatley and Ernst Boris Chain.Ernst Chain worked on its purification and managed to crystallize its sodium salt.He gave Dorothy some crystals, and those were the ones that Barbara worked on.The chemical formula of penicillin, uncertain at that time, was eventually found as the result of collaborations between Dorothy Hodgkin and Barbara Low at Oxford University with Charles William Bunn and Anne Turner-Jones at Imperial Chemical Industries (its Alkali Division in Winnington, Northwich).However, these were the early days of structure determination by X-ray diffraction of crystals, and the work was difficult and hard because there were so many experimental data to deal with and computational equipment was just beginning to be used for such types of scientific research.Techniques for interpreting the diffraction data in terms of molecular structure were being worked out from day to day.The use of Beevers-Lipson strips, which provided a method for calculating electron-density maps, took much time, whereas this has become much quicker since computer programs have been available.Penicillin was one of the largest structures studied at that time.This work in Oxford was described in more detail by Georgina Ferry in her book Dorothy Hodgkin: A Life, published by Grant Books in 1998.The resulting structure of penicillin that was determined in Oxford, however, was highly significant because the chemical formula for penicillin had not been known before the X-ray diffraction studies were completed.The crystal structure showed that penicillin contained a four-membered -lactam ring fused to a five-membered ring -an overall structure that is very active chemically (and favored by Howard Florey in Oxford and by Professor Woodward at Harvard).This finding of a -lactam ring was appropriate for its biochemical action of interference with the three-dimensional structure within bacterial cell walls.
Author: Jenny P. Glusker
Institution: Fox Chase Cancer Center
Language: English
Subfield: History
Field: Arts and Humanities
Domain: Social Sciences
Open Access status: bronze
OpenAlex ID: W2956133321