Search

Saturated thalassic brines are among the most physically demanding habitats on Earth: few microbes survive in them. Salinibacter ruber is among these organisms and has been found repeatedly in significant numbers in climax saltern crystallizer communities. The phenotype of this bacterium is remarkably similar to that of the hyperhalophilic Archaea (Haloarchaea). The genome sequence suggests that this resemblance has arisen through convergence at the physiological level (different genes producing similar overall phenotype) and the molecular level (independent mutations yielding similar sequences or structures). Several genes and gene clusters also derive by lateral transfer from (or may have been laterally transferred to) haloarchaea. S. ruber encodes four rhodopsins. One resembles bacterial proteorhodopsins and three are of the haloarchaeal type, previously uncharacterized in a bacterial genome. The impact of these modular adaptive elements on the cell biology and ecology of S. ruber is substantial, affecting salt adaptation, bioenergetics, and photobiology. halophile | lateral gene transfer | convergence | prokaryotic evolution | rhodopsins

The complete genome sequence of Enterococcus faecalis V583, a vancomycin-resistant clinical isolate, revealed that more than a quarter of the genome consists of probable mobile or foreign DNA. One of the predicted mobile elements is a previously unknown vanB vancomycin-resistance conjugative transposon. Three plasmids were identified, including two pheromone-sensing conjugative plasmids, one encoding a previously undescribed pheromone inhibitor. The apparent propensity for the incorporation of mobile elements probably contributed to the rapid acquisition and dissemination of drug resistance in the enterococci., The Gram-positive bacterium Enterococcus faecalis is a natural inhabitant of the mammalian gastrointestinal tract and is commonly found in soil, sewage, water, and food, frequently through fecal contamination (1). E. [...]

Research presents a comparison of the whole-genome of Mycobacterium tuberculosis clinical strain CDC1551 with the laboratory strain H37Rv. Data show extensive polymorphisms among M. tuberculosis strains conferring genetic variation, which play a role in their pathogenesis and immunity.

G. sulfurreducens, a member of the δ-Proteobacteria and of the family Geobacteraceae, is an important component of subsurface biota. Geobacter spp. generate energy as adenosine triphosphate by using metal ion [...], The complete genome sequence of Geobacter sulfurreducens, a δ-proteobacterium, reveals unsuspected capabilities, including evidence of aerobic metabolism, one-carbon and complex carbon metabolism, motility, and chemotactic behavior. These characteristics, coupled with the possession of many two-component sensors and many c-type cytochromes, reveal an ability to create alternative, redundant, electron transport networks and offer insights into the process of metal ion reduction in subsurface environments. As well as playing roles in the global cycling of metals and carbon, this organism dearly has the potential for use in bioremediation of radioactive metals and in the generation of electricity.