. The actinomycetes. Actinomycetales. HISTOUKWI. BAC' 9 2. The Soil rrriixl {1900-1919) Just as tho first period was initiatod and greatlj^ iuHiicMiced by tlie work of C.'ohn and Harz, the second period may be said to have been initiated by the work of W. H. lieijer- inck, on the role of aetinoniycetes in soil processes. It was soon followed by that of TTiltner and Stormer, on th(> aetiiioniycete population of the soil. While studies on the pathogenicity and classification of aetino- niycetes continued during this period, as in the work of Sanfeli('(>, Wright, and many others, ev
. The actinomycetes. Actinomycetales. HISTOUKWI. BAC' 9 2. The Soil rrriixl {1900-1919) Just as tho first period was initiatod and greatlj^ iuHiicMiced by tlie work of C.'ohn and Harz, the second period may be said to have been initiated by the work of W. H. lieijer- inck, on the role of aetinoniycetes in soil processes. It was soon followed by that of TTiltner and Stormer, on th(> aetiiioniycete population of the soil. While studies on the pathogenicity and classification of aetino- niycetes continued during this period, as in the work of Sanfeli('(>, Wright, and many others, ever-growing attention was being paid to the saprophytic actinomycetes, their physiology, and their role in nature, thus resulting in the broadening of our under- standing of actinomycetes as a large and im- portant group of microorganisms. In 1900, Beijerinck published a paper on the activities of an organism belonging to the group of Siiprophytic actinomycetes, designated as Streptothnx chromogena. This organism belonged to the ^•ery large group of actinomycetes now included in the genus Streptomyces. Beijerinck attempted to throw light upon its physiology and its role in soil transformations. lie pointed out that actino- mycetes in general are ()inni\()n)us organ- isms, capable of living in ;iii cnxironment rich in organic matter as well as in a very poor en\ironment. lOven distilled water and an ordinary laboratory atmosj)here are suffi- ci(Mit for the growth of some of these forms. Beijerinck emphasized, however, that ac- tinomycetes are unabk^ to carry out such processes as the fixation of ni- trogen, an ability ascribed to them later, on insufhcient grounds, by others. He also found that actinomycetes produce, in glucose me- dia, traces of acid, probably lactic, and that they are able to reduce nitrate to nitrite. It was suggested that, under certain conditions, the last process may lead to losses of nitro- gen through the interaction of nitrites with ammoni
Size: 1943px × 1286px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcoll, bookpublisherbaltimorewilliamswilkins
