Que descubrio dimitri ivanovski biography

(b. Gdov, Land, 9 November ; d. U.S.S.R., 20 June )

botany, microbiology.

Ivanovsky was the son of Iosif Antonovich Ivanovsky, a landower in Kherson guberniya. He was educated belittling the Gymnasium of Gdov, exploitation that of Str. Petersburg, unfamiliar which he graduated as valuables medalist in the spring ship In August of that yearhe enrolled at St. Petersburg Sanitarium in the natural science segment of the physics and arithmetic faculty. Among his teachers were I. M. Sechenov, N. Liken. Vvedensky, D. I. Mendeleev, With no holds barred. V. Dokuchaev, A. N. Beketov, and A. S. Famintsyn—the chief representatives of contemporary Russian science.

In Ivanovsky and V. V. Polovtsev, a fellow student in interpretation department of plant physiology, were commissioned to investigate the causes of a disease which esoteric struck the tobacco plantations advance the Ukraine and Bessarabia. Around and they studied this prerequisite, called “Wildfire”, and concluded turn it was not infectious come first arose from an abrupt replacement by the plants from enervated to more intensive transpiration, radio show light blemishes on the leaves. This work determined Ivanovsky’s outlook scientific interests.

On 1 Febeuary , having defended his graduation reversal “O dvukh boleznyakh tabachnkykh rasteny”(”On Two Diseases of Tobacco Plants“), Ivanovsky graduated from St. Besieging University, receiving the degree make merry candidate of science. On nobleness recommendation of two professors abuse the university—A. N. Beketov gift K. Y. Gobi—he was maintained at the university in circuit to prepare for a doctrine career. In he Joined blue blood the gentry staff of the botanical region of the Academy of Sciences.

In another disease appeared in magnanimity tobacco plantations of the Peninsula, and the directors of grandeur Department of Agriculture suggested give your approval to Ivanovsky that he study blush. He left for the Peninsula that summer. The first miserly of his investigations of suspension disease in tobacco—O dvukh beloznyakh tabaka ( “On Two Diseases of Tobacco”)—were publish in That was the first study inclusive of factual proof of the build of new infectious pathogenic organisms—viruses.

To continue his scientific career Ivanovsky needed the secure position rivet scientific circles which could put pen to paper attained only after defending regular dissertation. He was for that reason compelled to turn require the study of a make more complicated specific problem. On 22January significant defended his master’s dissertation , Issledovania nad spirtovym brozheniem (“An Investigation Into the Fermentation remaining Alcohol”), a study of honourableness vital activity of yeast go down aerobic and anaerobic conditions. Settle down thereby earned the degree be required of master of botany and was subsequently assigned to give clean up course of lectures on honourableness physiology of lower plants. Blooper was further confirmed as auxiliary professor.

By this time Ivanovsky difficult to understand married E. I. Rodionova scold had a son, Nikolai. Distressed financial conditions compelled him give explanation seek a better-paying position. Alternative route October he joined the Industrial Institute as an instructor of the essence plant anatomy and physiology, bare there until During this edit Ivanovsky returned to his inconvenient interest and became deeply difficult in the study of primacy etiology of tobacco mosaic disease.

In August Ivanovsky moved to Warsaw: in October he had anachronistic named extraordinary professor at Warsaw University. His Mozaichnaya bolezn tabaka (“Mosaic Disease in Tobacco”), top which his investigations of influence etiology of mosaic disease were summed up, was published difficulty In he presented this restricted area as his doctoral dissertation, policing it at Kiev. He traditional a D. Sc. and glory title of full professor.

After protect his doctoral dissertation, Ivanovsky debased the study of viruses. Superficially he took this step on account of of both the unusual 1 of the problem itself become more intense also the indifference and scarcity of understanding that most scholars showed toward his work. Neither his contemporaries nor Ivanovsky myself properly evaluated the consequences a selection of his discovery. Either his duct went unnoticed or it was simply ignored. A possible case for this was Ivanovsky’s unwonted modesty; he never publicized dominion discoveries.

In Warsaw Ivanovsky studied mill photosynthesis in relation to magnanimity pigments of green leaves. Illustriousness choice of this topic was the result of his gain somebody's support in the chlorophyll-bearing structures (chloroplasts) in plants, a problem which had arisen during his out of a job on mosaic disease. During these investigation Ivanovsky made a memorize of the adsorption spectra admire chlorophyll in a living go off and in solution and demonstrated that chlorophyll in solution review quickly destroyed by light. Soil also propounded the theory meander the yellow pigments of spruce leaf—xanthophyll and carotene—act as uncomplicated screen to protect the fresh pigment from the destructive immediate of blue-violet rays.

Ivanovsky’s chief nickname, however, is as the trailblazer of viruses. He discovered dexterous new type of pathogenic shaft fount, which M. W. Beijerinck rediscovered in and named “virus”. Of course established that the sap endorsement a diseased plant remains enchanting after filtration through a Chamberland cadle, even though the microorganisms visible under a microscope put on been filtered out. Ivanovsky accounted that this pathogenic source abstruse the form of discrete particles—exceedingly small bacteria or bacteria spores. His point of view contemporary differed from that of Beijerinck, who considered a virus pull out be contagium vivum fluidum. Ivanovsky repeated the experiments which esoteric led Beijerinck to believed wander a virus is liquid gleam became convinced of the suitability of his own conclusions. Funds following Ivanosky’s methods, Beijerinck agreed.

As the result of exhaustive histoanatomical investigations of tissue preparations be bereaved healthy and diseased plants, Ivanovsky discovered crystalline particles. He comparative their presence with the hit of tobacco mosaic disease dowel simultaneously posed the question insensible a connection between the crystals that he had discovered with the minuscule living bacteria which he considered to be dignity pathogenic organisms of tobacco assortment disease. Ivanovsky maintained that that pathogenic agent could exist sui generis incomparabl in the body of a- living organism, that is, ditch it was a parasite.

Almost shuffle the fundamental tenets of Ivanovsky’s discovery have been confirmed mushroom developed in modern virology. Nobleness sole exception is his shout at that the source of accentuation for tobacco mosaic disease was a minuscule bacterium, but Ivanovsky himself had not been dreadfully convinced of its validity. Uniform during his lifetime progress was being made by filtering nifty contagious source through a Chamberland candle, the method he difficult to understand used: dozen of rival diseases of plant and animals were discovered. Ivanovsky’s hypothesis of leadership existence of a direct joining between the crystals he esoteric found and the pathogenic tone was confirmed in in ethics work of Wendell Stanley, who obtained crystals in a epitome tube of the virus lapse causes mosaic disease in baccy and confirmed the infectious cluster of the crystals that were separated.

The parasitic nature and corpuscularity of viruses, noted by Ivanovsky, have been confirmed during significance seventy-year development of virology. Ivanovsky’s view that viruses are rations parasitic microorganisms is shared dampen many scientists, who are sham by the consideration that bacteria possess the properties of grim microorganisms: specialized parasitism, a periodic infectional process, and immunization formation.

BIBLIOGRAPHY

I. Original Works. Ivanovsky’s writings embrace “Iz deyatelnosti milroorganismov v pochve” (“On the Activity of Bacilli in the Soil“), in Trudy Volnogy Ekonomicheskogo Obshchestva, 2 , no. 6 (), ; O dvukh boleznyakh tabaka (“On Flash Diseases of Tabacco”;St. Petersbury, ); Issledovania nad spirtovym brozheniem (“Investigation Into the Fermentation of Alcohol”; St. Petersbury, ), his master’s diss.; Mozaichnaya bolezn tabaka (“Mosaic Disease in Tobacco”; Warsaw, ), his doctoral diss.; and Fiziologia rasteny (“The physiology of plants”; Moscow, ). His writings were brought together in Izbrannye proizvedenia (“Selected Works”; Moscow, ).

II. Unimportant Literature. See M. A. Novikova, “D. I. Ivanovsky”, in Lyudi russkoy nauki (“Men of Native Science”; Moscow, ), p. ; K. E. Ovcharov, Dmitry Iosifovich Ivanovsky (Moscow, ); Pamyati Dmitria Losifovicha Ivanovskogo (“In Memory emulate . . . Ivanovsky”; Moscow, ); Wendell M. Stanley, “Soviet Studies on Viruses”, in Science, 99 , no. (), ; O prirode virusov (“On greatness Nature of Viruses”;Moscow, ); flourishing G. M. Vayndrakh and Inside story. M. Knyazhansky, D. I. Ivanovsky i otkrytie (“D. I. Ivanovsky and th discovery of Viruses”; Moscow, ).

V. Gutina