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On September 1, 1856, Ukrainian microbiologist, ecologist and soil scientist Sergei Nikolaievich Winogradsky was born, who pioneered the cycle of life concept. He helped to establish bacteriology as a major biological science.
Sergei Winogradsky was born in Kiev, which belonged to the Russian Empire. The young man finished his secondary education with the gold medal and entered the Imperial Conservatoire of Music in St Petersburg in 1875 to study piano. However, he decided to study chemistry and botany about two years later and was admitted to the University of Saint Petersburg, where he studied under Nikolai Menshchutkin and Andrei Sergeevich Famintzin. After receiving his master degree in 1884, Winogradsky continued his career at the University of Strasbourg and earned a great reputation for his work on sulfur bacteria. Winogradsky developed a method of culturing Beggiatoa by imitating its natural environment on glass slides and silica gel and he observed that the cells were rods and not, as it was previously assumed, pleomorphic .
The scientist settled in Zurich around 1888 and began investigating the process of nitrification, identifying the genera Nitrosomonas and Nitrosococcus, which oxidizes ammonium to nitrite, and Nitrobacter, which oxidizes nitrite to nitrate. Winogradsky's interest in nitrification continued throughout his career and he isolated several genera of nitrifying bacteria. The type species for the genus Nitrobacter, N. winogradskyi was named after the scientist. Years later, Winogradsky’s daughter Helen worked on nitrogen-oxidizing bacteria at the Pasteur Institute. She isolated and described the new genera Nitrosogloea and Nitrosocystis. In 1933, she coauthored a paper with her father on Nitrosospira [1,2].
Winogradsky returned to St. Petersburg around 1891 and was shortly after appointed director of the Institute of Experimental Medicine and editor of the journal, Archives of Science. In this period, he identified the obligate anaerobe Clostridium pasteurianum, which is capable of fixing atmospheric nitrogen and he was elected honorary member of the Moscow Society of Naturalists. Winogradsky retired from his post in 1905 and accepted a position as head of agricultural bacteriology at the Pasteur Institute at an experimental station at Brie-Comte-Robert near Paris, France. He retired from his active work life in 1940.