A unified model describing the role of hydrogen in the growth of desulfovibrio vulgaris under different environmental conditions.

A unified model for the growth of Desulfovibrio vulgaris under different environmental conditions is presented. The model assumes the existence of two electron transport mechanisms functioning simultaneously. One mechanism results in the evolution and consumption of hydrogen, as in the hydrogen-cycling model.

Phylogeny of dissimilatory sulfite reductases supports an early origin of sulfate respiration.

Microorganisms that use sulfate as a terminal electron acceptor for anaerobic respiration play a central role in the global sulfur cycle. Here, we report the results of comparative sequence analysis of dissimilatory sulfite reductase (DSR) genes from closely and distantly related sulfate-reducing organisms to infer the evolutionary history of DSR. A 1.

Phylogenetic analysis and development of probes for differentiating methylotrophic bacteria.

Fifteen small-subunit rRNAs from methylotrophic bacteria have been sequenced. Comparisons of these sequences with 22 previously published sequences further defined the phylogenetic relationships among these bacteria and illustrated the agreement between phylogeny and physiological characteristics of the bacteria. Phylogenetic trees were constructed with 16S rRNA sequences from methylotrophic bacteria and representative organisms from subdivisions within the class Proteobacteria on the basis of sequence similarities by using a weighted least-mean-square difference method.

Use of 16S rRNA analysis to investigate phylogeny of methylotrophic bacteria.

Small-subunit rRNAS from 24 gran-negative methylotropic bacteria have been sequenced. A phylogenetic tree was constructed on the basis of sequence similarities by using a weighted least-mean-square difference method. The methylotrophs were separated into coherent clusters in which bacteria in each group shared physiological characteristics.

Characterization of a methane-utilizing bacterium from a bacterial consortium that rapidly degrades trichloroethylene and chloroform.

A mixed culture of bacteria grown in a bioreactor with methane as a carbon and energy source rapidly oxidized trichloroethylene and chloroform. The most abundant organism was a crescent-shaped bacterium that bound the fluorescent oligonucleotide signature probes that specifically hybridize to serine pathway methylotrophs. The 5S rRNA from this bacterium was found to be 93.