Ingeneria Civil

Arehiv fiir Mikrobiologie, Bd. 20, S. 34--62 (1954).

(From the Hopkins Marine Station of Stanford University, Pacific Grove, Calif.)

Studies on Thiobaeiilus denitrifieans.
By
K. BAALSRUD and]~JELLRUN S. BAALSRUD~. With 8 figures in the text.

(Eingegangen am 9. November 1953.)

I. The cultivation ol Thiobacillus denitrificans.
During the course of an investigation of the carbondioxide assimilation b y representatives of the genus Thiobaeillu8 it became desirable to compare the behavior of T. thioparus and T. thiooxidans with that of T. denitri/icans. This made it necessary toisolate pure cultures of the "last-named organism. I t soon became apparent that the procedures used by B~IJ~RI~CK, LIESK~, and G~ttI~I~G, the only investigators who had :previously reported o n thesuccessful isolation of pure cultures, could be considerably improved by the introduction of some small but significant modifications. I n view of the fact that T. denitri/icans has not been generallyavailable, and that SIJD~I~I!~S, as late as 1946, reported to have failed completely in his attempts at isolating this bacterium in pure culture, we here present a description of the method which, inour hands, has given eminently satisfactory results, along with the reasons for adopting the specific changes. Experiments on some physiological and biochemical properties of the isolated strains havebroadened our knowledge of this remarkable bacterium; the results obtained are treated in subsequent sections, They m a y serve to show that T. denitrificans, now for the first time made easilyaccessible, possesses a number of characteristics which render it especially suitable for the study of certain unusual phenomena. ~

1, Brie] review o] previous studies.
Approximately a decade afterWIXOGI~ADSI~Y had firmly established his revolutionary concept of chemosynthesis, initiated by his classical studies on the suifur bacteria, and developed to its ultimate consequences through his...