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Gregorio Weber (July 4, 1916– July 18, 1997) was an Argentinian scientist who made significant contributions to the fields of fluorescence spectroscopy and protein chemistry.〔"Biophysical Journal, Volume 75, July 1998, pages 419-421"〕 Weber was elected to the National Academy of Sciences in 1975. ==Early Life and Education== Gregorio Weber was born in Buenos Aires, Argentina in 1917. He attended the University of Buenos Aires where he received his Doctor of Medicine degree in 1942. While a medical student, from 1939 to 1943, he worked in the Department of Physiology and Biochemistry as a teaching assistant for Bernardo Alberto Houssay who had already achieved renown as a physiologist for his work on the endocrine system and in particular the pituitary gland (Houssay shared the 1947 Nobel Prize for Physiology and Medicine with Carl and Gerty Cori). Weber continued his studies at the University of Cambridge under the guidance of Malcolm Dixon, well-known enzymologist, and, in 1947, earned a Ph.D. in biochemistry. His thesis, titled "Fluorescence of Riboflavin, Diaphorase and Related Substances", marked the beginning of the application of fluorescence spectroscopy to biomolecules.〔 A large portion of Weber’s thesis was devoted to measurements on the quenching of fluorescence of riboflavin and on development of a general theory of quenching by complex formation. This led to his first publication entitled: "The quenching of fluorescence in liquids by complex formation. Determination of the mean life of the complex". This paper was the first to demonstrate that fluorescence quenching can take place after formation of molecular complexes of finite duration rather than collisions. His second publication entitled "Fluorescence of riboflavin and flavin adenine dinucleotide", was the first demonstration of an internal complex in FAD. Years later he was to follow up this work with the first demonstration that NADH also formed an internal complex and with more complete characterizations of the excited state properties of FAD and NADH. From 1948 to 1952 Weber carried out independent investigations at the Sir William Dunn Institute of Biochemistry at Cambridge, supported by a British Beit Memorial Fellowship. At that time he began to delve more deeply into the theory of fluorescence polarization and also began to develop methods which would allow him to study proteins which did not contain an intrinsic fluorophore such as FAD or NADH (the fluorescence of the aromatic amino acids had not yet been discovered). To this end, he invested considerable time and effort in synthesizing a fluorescent probe which could be covalently attached to proteins and which possessed absorption and emission characteristics appropriate for the instrumentation available in post-war England. The result of two years of effort was the still popular probe dimethylaminonaphthalene sulfonyl chloride or dansyl chloride. With this tool in hand and with new instrumentation he began to investigate several protein systems, publishing his theory and experimental results in two classic papers published in 1952, namely, Polarization of the fluorescence of macromolecules. I. Theory and experimental method and Polarization of the fluorescence of macromolecules. II. Fluorescent conjugates of ovalbumin and bovine serum albumin. The theory paper (which contains an acknowledgement to F. Perrin for his suggestions) includes an extension of Perrin’s theory of depolarization due to rotation of ellipsoidal molecules. Specifically, Weber showed that Perrin’s complex equations, which required a knowledge of the orientation of the fluorophore’s absorption and emission oscillators with respect to the axis of rotation of the ellipsoid, could be considerably simplified if the fluorophores carrying the oscillators were assumed to be randomly oriented on the macromolecule. This paper also contained a formulation of the law of additivity of polarizations. Weber stayed at Cambridge as an independent researcher until 1953 when Hans Krebs recruited him for the new Biochemistry Department at Sheffield University. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Gregorio Weber」の詳細全文を読む スポンサード リンク
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