His father, Nikolay Andreevich Belozersky, was born into a Russian family that migrated to Central Asia, and worked as a lawyer in the judicial chamber.
Also, at this university, under the guidance of A. V. Blagoveshchensky, he made his first research work—an investigation of proton concentration in water extracts of some mountain plants’ leaves.
A. N. Belozersky was directly involved in the renovation and modernization of laboratories and participated in the creation of new places for practical classes.
In 1934, articles by A. R. Kiesel and A. N. Belozersky appeared in the journal "Hoppe-Seyler's Zeitschrift für Physiologische Chemie"[3] and then in 1935 in the "Scientific Notes of Moscow State University''.
Subsequently, the presence of RNA and DNA was confirmed in linden buds, onion bulbs, and wheat germ.
While Belozersky was studying bacteria, he noted the high content of nucleic acids in cells, amounting to 30% of the dry weight, unlike higher organisms.
Andrey Nikolaevich pointed out a new aspect (at the same time with T. Caspersson and J. Brachet): the relationship of the number of nucleic acids with the intensity of protein biosynthesis.
These conclusions were made by A. N. Belozersky long before the appearance of the "molecular biology" term associated with the publication in the journal "Nature" by James J. Watson and F. Crick on the establishment of a spatial model of the DNA molecule.
[6] Thus, as a result of research from 1939 to 1947, A. N. Belozersky obtained the first scientific information in the world on the content of nucleic acids in various bacterial species.
In a paper published in 1957 in Russian,[7] and in 1958 in English,[8] A. N. Belozersky and his student A. S. Spirin discovered an inconsistency between the composition of DNA and ribosomal RNA.
Soviet scientists have proved that the DNA-RNA-protein biosynthesis scheme requires that all elements be in a certain composite correspondence.
The data they provided showed that our ideas on a number of important points were too simplistic.” Soviet scientists discovered that there is a certain part of RNA in the cells that coincides in composition with DNA and is determined by its structure.
These studies were conducted from 1958 to 1965 in groups of the Moscow State University and the USSR Academy of Sciences, headed by A. N. Belozersky.
[10] Today, this direction is being developed by A. S. Antonov and other students of Belozersky.The scientific activities of the groups headed by A. N. Belozersky include the study of the species functional specificity of adaptive RNAs (G. N. Zaitseva), the study of changes in the amino acid composition of proteins in response to the substitution of nucleotides in DNA (A. S. Antonov), and the study of phosphate in the simplest organisms, particularly in aspects of its transfer from the environment, transport, accumulation, and forms of existence (I. S. Kulaev, M. S. Kritsky).
A. N. Belozersky studied the chemical structure of one of the most effective Soviet antibiotics, gramicidin S, first obtained by G. F. Gause and his wife M. G. Brazhnikova.
In the first works on this topic, the polypeptide nature of gramicidin was shown and its amino acid composition was determined (A. N. Belozersky, T. S. Paskhina).
A. N. Belozersky was interested in the question of the existence of complexes between nucleic acids and proteins (called "nucleoproteins") in in vivo systems.
He made an attempt to fractionate nucleoprotein samples and thus developed a methodological scheme for this process, which later played a major role in the study of nucleic acids.
Based on his experiments, Belozersky concluded that nucleic acids in cells exist in various complexes with proteins: unbound, labile, and firmly bound.
During his years at the N. F. Gamalei Institute of Epidemiology and Microbiology of the USSR Academy of Medical Sciences, A. N. Belozersky conducted studies of the antigenic and immunogenic properties of E. coli nucleoproteins.
In 1948, the Scientific Council of Moscow State University awarded Andrey Nikolaevich the first M. V. Lomonosov Prize [ru; uk] for his work "On the Nucleoproteins and Polynucleotides of Certain Bacteria."