[Ratio of metals during changes in the metabolism of photosynthetic bacteria]

The content of polyvalent metals was determined in the photosynthetic bacteria Rhodopseudomonas capsulata (Athiorhodaceae) and Chromatium vanda (Thiorhodaceae) isolated from the sediments of Lake Vanda in the Antarctic when the conditions of growth, photoheterophic and photoautotrophic, were changed. The ratio between Fe and Mn, Cu, V, Ni, Co, Cr was studied. The utilization of all polyvalent metals, Mn and Cr in particular, relatively increased in the conditions of autotrophic growth. Changes in the composition of bacterial cells (the content of protein, lipophilic substances, flavin) and their enzymatic activity (hydrogenases) were also assayed. Apparently, chemical composition may be used as a criterion for determining the taxonomy of organisms and the ecological conditions of their habitat.