Bacterial life and dinitrogen fixation at a gypsum rock.

The organisms of a bluish-green layer beneath the shards of a gypsum rock were characterized by molecular techniques. The cyanobacterial consortium consisted almost exclusively of Chroococcidiopsis spp. The organisms of the shards expressed nitrogenase activity (C2H2 reduction) aerobically and in light.

Biodiversity of denitrifying and dinitrogen-fixing bacteria in an acid forest soil.

Isolated soil DNA from an oak-hornbeam forest close to Cologne, Germany, was suitable for PCR amplification of gene segments coding for the 16S rRNA and nitrogenase reductase (NifH), nitrous oxide reductase (NosZ), cytochrome cd(1)-containing nitrite reductase (NirS), and Cu-containing nitrite reductase (NirK) of denitrification. For each gene segment, diverse PCR products were characterized by cloning and sequencing. None of the 16S rRNA gene sequences was identical to any deposited in the data banks, and therefore each of them belonged to a noncharacterized bacterium.

Heterotrophic bacteria growing in association with Methylococcus capsulatus (Bath) in a single cell protein production process.

The methanotrophic bacterium Methylococcus capsulatus (Bath) grows on pure methane. However, in a single cell protein production process using natural gas as methane source, a bacterial consortium is necessary to support growth over longer periods in continuous cultures. In different bioreactors of Norferm Danmark A/S, three bacteria consistently invaded M.

Relative abundance of denitrifying and dinitrogen-fixing bacteria in layers of a forest soil.

The populations of N(2)-fixing and denitrifying bacteria in an acid forest soil near Cologne were characterized by gene probing. The DNA isolated from the soil for this purpose was suitable for DNA-DNA hybridization using 0.4-0.