Gunnar Blix and his discovery of sialic acids. Fascinating molecules in glycobiology

Gunnar Blix (Figure 1) was born in Lund in 1894. He was the son of a famous physiologist, Magnus Blix. After medical school, he started in research and defended his thesis entitled Studies on Diabetic Lipaemia in 1925 at the University of Lund. Previously he had been employed by the university as a research fellow in anatomy and medical chemistry, and for shorter periods of time he also practised as a physician. Figure 1. Gunnar Blix in 1970. Directly after his dissertation he moved to Uppsala, where he obtained a position in 1926 as associate professor (laborator) and four years later succeeded Carl Thore Morner as professor in Medical and Physiological Chemistry. This professorship had been created in 1853. Gunnar Blix held the professorship for 31 years (1930–1961). During the years 1956–1961 he also served as Deputy Vice Chancellor in the university administration. He was Editor-in-Chief for Acta Societatis Medicorum Upsaliensis (from 1972 Upsala Journal of Medical Sciences) between 1943 and 1969. After his retirement he continued to work until 1970 as executive member of the Swedish Foundation for Nutritional Research (Stiftelsen Svensk Naringsforskning). Gunnar Blix died on 10 June 1981 at the age of 87 years. Those who met and got to know Gunnar Blix remember him as an honest, dutiful, and humble person who generously gave of his ideas and devoted much of his time to teaching students in the medical school and graduate students in his research group. He became a highly worthy successor to his predecessors of the professorship (Table I, Figure 2). His time as professor coincided with an important period in the development of the scientific field of medical and physiological chemistry. He became internationally well known and a leading scientist within his own research field. Table I. Predecessors to Gunnar Blix for the professorship in Medical and Physiological Chemistry at Uppsala University. Figure 2. Four generations of professors in Medical and Physiological Chemistry. Sitting from left: Carl Thore Morner, Sven Gustaf Hedin, Olof Hammarsten. Standing: Gunnar Blix (1930). Gunnar Blix enjoyed public confidence, and it was by no means accidental that he was assigned to numerous commissions of trust within his own faculty, within the university, and also nationally. He was a member of the organizing committees for the formation of both Gothenburg and Umea Medical Schools in 1947 and 1958, respectively. In the case of Umea, all existing universities in Sweden voted against the establishment of a medical school there. Blix, however, made a reservation against the negative attitude from Uppsala and thereby he succeeded in convincing the Swedish government to proceed with the plans, which later on led to the formation of Umea University. The Faculty of Medicine in Uppsala initially became ‘mother faculty’ to the new medical faculties in both Gothenburg and Umea and later on also in Linkoping. When Blix became a member of the Faculty of Medicine in Uppsala, his department of medical chemistry was housed in an old building called ‘Gamla Kemikum’ (Old chemistry institute) located in Engelska parken (The English park). This building (Figure 3) was erected in 1853–1859 and in time became more and more worn out. The sanitary conditions, for instance, made it gradually impossible to continue to work there. The government therefore decided (in 1941) to construct a new building, to be shared by the Departments of Medical Chemistry and Pharmacology. Blix took a very active role in the planning of the various facilities and in the moving to the new building (Figure 4). Due to the Second World War the construction materials were not of the best quality, and the whole building project was also delayed. Not until 1946 did the transfer actually take place. Figure 3. ‘Gamla Kemikum’, later called Philologicum. Figure 4. The Departments of Medical Chemistry and Pharmacology, located at Stockholmsvagen 19 (later named Dag Hammarskjolds vag). Gunnar Blix was also engaged as an inspector for two ‘student nations’ in Uppsala: 1938–1943 for ‘Gotlands nation’ and 1943–1961 for ‘Norrlands nation’. When he resigned from his inspectorship he was honoured with a Festschrift in which Blix’s instrumental role for the establishment of Umea University is emphasized. In addition, the student dormitories ‘Norrlands-gardarna’ were built during Blix’s time as inspector. Blix covered a broad area in his research. His interest in lipid chemistry, which was documented already in his thesis, continued through the years. In this context two important discoveries should be mentioned. The first came already in 1933, in his studies of lipids in human brain tissue, when he isolated and characterized the first sulfatide known at this time. He showed that it was composed of sulfuric acid, cerebronic acid, sphingosine, and galactose (Figure 5) (1). Figure 5. Structure of a galactocerebroside (today usually called galactosphingolipid). In sulfatides the R at carbon 3 in galactose is a sulfate group. A glycosphingolipid containing sialic acid in the carbohydrate unit of the cerebroside is named ganglioside. The other important discovery was made together with Arne Tiselius and Harry Svensson in 1941 when Blix demonstrated the existence of lipoproteins and that the blood lipids preferentially were transported in the β-globulin fraction obtained on serum electrophoresis (2). The most important discovery, however, was made in 1936. This year Gunnar Blix isolated a crystalline compound from bovine submaxillary mucin (3). This compound was later designated ‘sialic acid’ by Blix. Much of the further work on sialic acid(s) was carried out during the 1950s and in competition with several groups worldwide. Two of these important discoveries were published in Hoppe-Seyler’s Zeitschrift fur Physiologische Chemie, published by the Springer Verlag in Germany. This journal had high impact, as we say today, and German was an important scientific language in those days. Mainly during the 1960s, but also after his retirement, Blix was very interested in research related to nutrition, food intake, and public health. The importance of iron in food and the problem of sufficient iron intake in connection with a low total calorie intake was discussed in some of his publications. In his role as executive member in the Swedish Foundation for Nutritional Research and also chief editor for the Swedish journal Naringsforskning (Nutritional research) he was able to influence the quality of ongoing nutritional research in Sweden at the time. Blix became a member of the Royal Swedish Academy of Science in 1956 and received ‘Bjorken’s award’ (Bjorkenska priset) in 1960 from Uppsala university for his studies on sialic acid. In 1965 he was awarded an honorary doctoral degree in medicine at the University of Oslo.