Rhodopseudomonas viridis, nov. spec., ein neu isoliertes, obligat phototrophes Bakterium

Zusammenfassung

Nach Untersuchung von Morphologie, Feinstruktur und Ernährungsphysiologie wird ein neu isoliertes grünes Bakterium in die Gattung Rhodopseudomonas eingeordnet und der Artname Rhodopseudomonas viridis vorgeschlagen.

Summary

Rhodopseudomonas viridis was isolated from different waters near Freiburg im Breisgau. It is a gramnegative bacterium which is motile by means of polar flagella. Cells are usually distinctly rod-shaped, occasionally the rods are lightly curved. The size is variable, the dimensions 0.6 to 0.8 by 1.5–2.5 μ. Dense suspensions of this Rhodopseudomonas species are green coloured. The colour is changed in older cultures to a dirty brown-green. The absorption-maxima of the in-vivo spectrum at 400, 606 and 1020 nm are attributed to bacteriochlorophyll b, while the peaks at 451 and 483 nm reflect the presence of carotenoids. The bacteria grow only anaerobically in the light. They are strictly photo-organotroph. Heavy growth is observed in media which contain malate, succinate, pyruvate or acetate as carbon source and ammonia as nitrogen source. p-amino-benzoic acid, biotin and vitamin B are required. Yeast extract (0.05%) and casamino acids stimulate but fatty acids with the exception of acetate inhibit growth. No development is observed with carbon dioxide as sole carbon source. Gelatine is not liquefied. Nitrate is not reduced to nitrite.