Belozerskii, Andrei Nikolaevich

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BELOZERSKII, ANDREI NIKOLAEVICH

(b. Tashkent, Russia. 29 August 1905; d. Moscow, U.S.S.R., 31 December 1972)

biochemistry.

Belozerskii was born into a family of lawyers. His parents died when he was young, and he was raised first by relatives and then in an orphanage at Gatchina. where he finished high school in 1921. From 1922 to 1927 Belozerskii studied at the Faculty of Physics and Mathematics of Central Asian University (now Tashkent University). While there he became interested in the physiology and biochemistry of plants, and after graduation he undertook advanced studies in biochemistry.

During his graduate studies Belozerskii traveled to Moscow for practical training. There he met A. R. Kiesel, who invited him to work at the biochemical laboratory of the Polytechnical Museum in Moscow upon completing his graduate work. Belozerskii went to work in the laboratory in 1930, and by the end of the year he and Kiesel had organized the department of plant biochemistry at Moscow State University. He became an assistant there, and two years later he was named an associate professor. In 1943 he defended his dissertation. “Nukleoproteiny inukleinovye kisloty rastenii” (Nucleoproteins and polynucleic acids of plants). In the same year Belozerskii was appointed professor at the Faculty of Biology of Moscow University. Between 1946 and 1960, in addition to his work at the department of plant biochemistry, he headed the laboratory (which he had organized) of microorganic biochemistry at the A. N. Bach Institute of Biochemistry of the Academy of Sciences of the U.S.S.R. In 1960 he became chairman of the department of plant biochemistry, replacing Aleksandr I. Oparin.

In 1962 Belozerskii was elected a full member of the Academy of Sciences. The following year he organized and headed the department of virology at Moscow University, and in 1965 he established at the university the Interdepartmental Laboratory of Bioorganic Chemistry and Molecular Biology (later named for him), which, along with the M. M. Shemyakin Institute of Bioorganic Chemistry and the Institute of Molecular Biology of the Academy of Sciences, forms the major center for the development of physicochemical biology in the Soviet Union. In 1971 Belozerskii was elected vice-president of the Academy of Sciences of the U.S.S.R. and led its research work in chemistry and biology.

Belozerskii’s major research interests focused on the chemistry and biology of proteins, primarily of nucleic acids. It was through the study of these substances that Belozerskii hoped to decipher the chemical structure of the genetic mechanism. Therefore, his first works uere aimed at obtaining the chemical characteristics of plant proteins of definite types and patterns. By the 1930’s he had predicted that, in addition to proteins, nucleic acids could be substances that possess both chemical and biological characteristics simultaneously.

The study of plant nucleic acids led Belozerskii to one of his most important discoveries: in 1936 he uncovered DNA in plants through separating thymine from the nucleic acids of the horse chestnut. Until this time DNA was considered to be a specific form of animal nucleic acid and RNA of plant nucleic acid. Continuing this research, by the end of the 1930’s Belozerskii had shown the universal occurrence of DNA and RNA in higher and lower plants and in microorganisms. He traced the regularities in the changes of DNA and RNA during the ontogenesis of plants and proved the species specificity of DNA in microorganisms. This important research formed the basis for the principles of the systematica of organisms.

After Erwin Chargaff developed more sophisticated methods that permitted a precise analysis of DNA and RNA in the cell (early 1950’s), the systematic study of the nucleotide composition of DNA and RNA in various groups of microorganisms began. Thenucleotide composition of bacteria was determined to be directly connected to their evolutionary systematics. It was also shown that despite enormous variations in the composition of DNA, the nucleotide composition of RNA in bacteria changed fairly little from type to type. In 1957 Belozerskii and A. S. Spirin discovered the fraction of RNA that corresponded to the composition of cellular DNA. They proposed that it was this fraction that carried information from DNA to the proteins in the process of protein biosynthesis. This was viewed as the beginning of the complete scheme of the biosynthesis of proteins and the clarification of the “central dogma” of molecular biology. Consequently the existence of messenger RNA (m-RNA) was proved experimentally. (It was isolated in 1961.)

The research on the nucleotide composition of various species of organisms led Belozerskii to posit the possibility of using data on the chemical composition of the genome to establish a natural classification of living organisms. He and his students developed a new branch of biology, called genosystematics or molecular phenogenetics.

Belozerskii was elected a member of the Leopoldina Academy (German Democratic Republic). In 1948 he was awarded the Lomonosov Prize and in 1969, the title Hero of Socialist Labor, the highest honor of the Soviet Union.

BIBLIOGRAPHY

I. Original Works. Belozerskii’s writings include “On the Nucleoproteins and Polynucleotides of a Certain Bacteria” in Nucleic Acids and Nucleoproteins, vol. 12 of Cold Spring Harbor Symposia on Quantitative Biology (Cold Spring Harbor, N.Y., 1947), 1–6: Nukleoproteidy i nukleinovye kisloty rastenii i ikh biologischeskoe znachenie (Nucleoproteins and nucleic acids of plants and their biological significance; Moscow, 1959); Instituts Solvay, Institut International de Chimie. Nucleoproteins (New York, 1960); Prakticheskoe rukovodstvo po biokhimii rastenii (Practical handbook on the biochemistry of plants; Moscow, 1961), written with N. I Proskuriako; and Biokhimia nukleinorykh kislot i nukleoproteidov (Biochemistry of nucleic acids and nucleoproteins; Moscow, 1976), which consists of selected works.

II. Secondary Litertaure. Short articles are in Modem Men of Science, I; and Modern Scientists and Engineers, I (1980), 73–75. See also Andrei Nikolaevich Belozersky, Materialy k biobibliografii uchenykh SSSR (Materials toward The biobibliography of scientists of the U.S.S.R.), ser. biokhimii, no. 7 (Moscow, 1968)

Aleksei Nikolaevich Shamin