Beijerinck is not universally known to the public as are Pasteur and Koch. A major reason is that he worked on many microorganisms related to plants, rather than those related to diseases of man and his domestic animals. But among scientists he is particularly famous for having isolated and characterized the first virus--that of tobacco mosaic. He also was first to demonstrate the nitrogen-fixing capability of bacteria such as Bacillus radicicola and Azotobacter species. His discovery of such bacterial characteristics as sulphate reduction, butyric acid fermentation, urea hydrolysis and elucidation of oxygen relationships among bacteria (and many other diverse organisms) made him a true "scientist's scientist." In the field of virology, Beijerinck is famous for having demonstrated the first filterable infectious agent (now called a virus). He also worked out its intracellular reproduction, unknown then. All scientists and especially all virologists recognize his achievement of demonstrating the tobacco mosaic virus as the first "organism" to be so characterized.

He also was a prime mover in the establishment of what is known today as "general microbiology" as a major discipline. When schools had no set place for microbiology, he established the Delft School of Microbiology, which has had a great impact on the development of microbiology all over the world in this century. A stream of famous disciples, such as Van Iterson and A. J. Kluyver, continued their microbiology research in Delft, which from there later spread to all the world.

Martinus Beijerinck was born on March 16, 1851 in Amsterdam, the Netherlands. In his childhood, he had a tremendous love of plant life. At the age of 16 he won a botanical contest with the collection of 150 different species of plants. He was considered a very awkward young person, probably because of his fascination with plant life and nature, which excluded him from the usual activities and play of boyhood and youth with others of his own age.

At the age of 18 he began his studies at Delft Polytechnical School, majoring in chemistry. He was a hardworking student. He spent hours in the laboratory, studying the characteristics of plants, in addition to his course work. While a student, he met J. H. Van't Hoff and they became very good friends. They performed many experiments together, not only in the laboratory, but in their living quarters. Beijerinck graduated in 1872 and started attending the University of Leiden in the same year. He continued his graduate work and received his doctorate in 1877.

Following graduation from the university he began his teaching career. His first position was as a teacher of botany in the Agriculture High School at Wageningen. While teaching, he continued his research activities on the side, doing work on plant galls. He was a perfectionist, both in research conducted on his own, but also in the classroom and school laboratory. He was a demanding teacher but one without tact. He yelled at his students, shouting his demands and berating them for any errors. Although they recognized him as a great source of scientific knowledge, his students were not very fond of him. He was not a popular teacher. This greatly disappointed Beijerinck, since he could not understand the outlook on life of the "normal" youth and student. He simply could not understand why they wanted to waste their time socializing and dating and just having fun when there was serious scientific work to be done!

To Beijerinck, there was nothing more interesting than science. Botanical research was the love of his life. He did all experiments exactly as planned and he got highly accurate results. His work was recognized by the scientific establishment in Holland and he became a member of the Royal Academy of Sciences at Amsterdam. While he liked to teach, he was, for reasons mentioned earlier, unpopular--even disliked --by his students. He often displayed his anger at what he considered the "lazy" students by using coarse language and yelling. Then he would withdraw to himself and have a fit of depression. But he truly desired to help his students and was indeed a big inspiration to those who understood his vast knowledge and dedication to science. The man who became an eminent botanist, Dr. G. Van Iterson, and another who became a famous microbiologist, Prof. A. J. Kluyver, were both students of Beijerinck and both appreciated him for the true scientist he was and for what he transmitted to them. As a consequence, both of them made great contributions to the development of microbiology in this century.

In 1885, Beijerinck changed his job and became a microbiologist at "Nederlandsche-Gist-en-Spiritusfabriek" (Netherlands Yeast and Alcohol Manufactory) in Delft. This was a job which paid well and Beijerinck now really came into his proper element. He had the chance to obtain excellent equipment for his research work and establish an outstanding laboratory for plant microbiology. This was unusual as most microbiologists at the time focussed upon human and animal disease, following the lead of Pasteur and Koch. Beijerinck continued to work on plant galls and related microbiological problems. He made an outstanding discovery, which would greatly affect agriculture, when he isolated root-nodule bacteria in pure culture. During this period, he spent long hours in the laboratory, sometimes spending the entire night without sleep, trying to make progress in his experiments. He actually spent most of his time in the laboratory. He was also working on a multitude of projects.

In 1894, he truly made history with the publication of a paper on Spirillum desulfuricans, a sulphate reducer. His interest in sufate reduction was related to the need of a nearby yeast factory. The factory was confronted with the use of canal water for its steam boilers; the water caused a built-up of calcium sulfate from its bacterial content. His research in benefit of industry, like that of Pasteur, resulted in a solution to the problem. From both his basic and applied research, his accomplishments brought recognition. His reputation as a brilliant young scientist was becoming known to the scientific community in the Netherlands.

Recognizing his achievements, in 1895, the Government of the Netherlands created a new and special professorship with him in mind. This was not only a position but included a new laboratory for general and applied microbiology at the Polytechnic School in Delft. Astute goverment officials recognized that his position at the Netherlands Yeast and Alcohol Manufactory did not allow him sufficient scope. .The curriculum at the Polytechnical School did not include any biology at that time and for lack of a more appropriate allocation, his position was incorporated in the chemistry department. With the change, Beijerinck became excited about these new opportunities, since it meant going back to the school where his career started. He stayed on at this position until his retirement in 1921. By then the Delft laboratory, under his direction, had acquired world-wide renown. .

Beijerinck continued his research, expanded his knowledge and making further world contribution to microbiology. He was awarded many honors. In 1903, he was appointed a Knight of the Order of the Nederlandsche Leeuw. He was awarded the unusual distinction of honorary member of the Royal Botanical Society of Edinburgh in 1906. In 1921, he was made a commander of the Order of Orange-Nassau, and in 1926, he was elected Foreign Minister of the Royal Society of London.

Among many scientific contributions of Beijerinck, perhaps his major one was the application of the principle of enrichment culture techniques. Through these special techniques, he was able to reveal the major biotransformation of matter by specific bacteria. He illustrated the role of microorganisms in natural processes and

indicated numerous applications of activities of these microscopic forms of life to both agriculture and industry. Although many of his investigations were with the intent of direct application, a by-product of his studies was greater theoretical knowledge and the discovery of principles which interpreted the roles of microbes in nature. Because of emphasis on these principles he was perhaps the first microbiologist to emphasize the ecological approach to microbiology.

His own words were: "In an experimental sense, the ecological approach to microbiology consists of two complimentary phases which give rise to an endless number of experiments. On the other hand, it leads to investigate the conditions for the development of organisms that have for some reason or other, perhaps fortuitously, come to our attention, on the other hand, to the discovery of living organisms that appear under predetermined conditions, either because they alone can develop, or because they are the more fit and win out over their competitors. This latter method, in reality nothing but the broadest application of the elective culture method, is especially fruitful and truly scientific, and it is no exaggeration to claim that the rapid and surprising advances in general microbiology are due to this methodology". (Microbiology: Historical Contributions, Page 181.)

Martinus Beijerinck retired in 1921, on his seventy-first birthday. His friends and pupils presented him with a five-volume set of his publications and contributions to science especially bound for the occasion.

Beijerinck never married. In fact, he never dated or courted anyone, nor did he have female friends. He believed that a scientist should never marry because that would interfere with his work. His two sisters, however, did live with him. Although he retired in 1921, he never gave up his research work. In 1927, he submitted a paper entitled "On the Positon of Leaves" to the Royal Academy. He died on January 31, 1931 in Gorssel, the Netherlands, after 80 years. The most amount of his time was spent directly on microbiology. His love and even passion for botany and microbiology is still a great inspiration to all microbiologists (especially young microbiologists) and also, people interested in ecology. Although we live much more sophisticated lives in our society today, we have much to learn from Beijerinck's pioneering in ecological microbiology. He shared his wealth of knowledge widely with many people and was a model scholar and teacher. Moreover, he was simply a fine person.