Shallows of the lower Danube as additional sources of potamoplankton

This paper presents studies on the algal flora of the Bulgarian Danube section during three summer periods (1980–1982) and during the four seasons of 1987/1988. The following variables were investigated: 1) species composition of the river phytoplankton and the phytobenthos; 2) frequency quotients of the species; 3) number of species at the investigated sites; 4) phytoplankton numbers and biomass; 5) floristic similarity between the sites. The data show the existence of a dynamic connection between phytoplankton and phytobenthos. The shallows in the midstream and river arms play an important role as potamoplankton sources during the periods of low waters. It is comparable with the role of the adjacent wetlands to which previously priority was given. This is especially so below 597th river kilometer.Academia Naturalis Heidelberg     

Atypical R–S Dissociation in Azospirillum brasilense

It was found that atypical R–S dissociation in the type strain A. brasilense Sp7 is not accompanied by drastic changes in the polysaccharide moieties of bacterial lipopolysaccharides but is rather due to different contributions of two O-specific polysaccharides (found in both R and S dissociants) to the age-dependent architectonics of the cell surface.     

Tocopherol-binding proteins in membranes of rat liver mitochondria

The use of the adsorption chromatography on the hydroxyl apatite makes it possible to yield and partly purify the triton X-100-solubilized mitochondrial protein fraction of the rat liver able to bind specifically [3H]-alpha-tocopherol. The method permits removing simultaneously both free detergent and [3H]-alpha-tocopherol from the protein mixture without disturbance of the established equilibrium. When compared with methods used for the removal of free hydrophobic ligands in the in vitro binding experiments, the applied method is the most effective.