Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CHROMATIUM”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 811 records · Page 45Linked to original sources
PubMedDate not supplied

[Effect of temperature on the phototransformation of purple sulfur bacteria bacteriochlorophylls and isolated chromatophores].

Photobleaching of P890 was shown to be independent of temperature within the range of +20 to -160 degrees C in purple sulphur bacteria and isolated chromatophores under oxidative conditions; therefore changes in the absorption at 890 nm are due to the primary photoact. No changes were detected in the absorption at 850 nm upon a slight decrease of temperature, which suggested the absorption at 850 nm upon a slight decrease of temperature, which suggested the conformation nature of these changes. The effect of temperature, which suggested the conformation nature of these changes. The effect of temperature on the photoinduced changes of absorption under reductive conditions seems to be due to the electron transport and the accompanying processes being blocked. The effect of temperature on the kinetics of P890+ reduction in the darkness under conditions when the cytochromes are preliminarily oxidized is determined by the participation of the secondary electron acceptors in this process. A decrease in temperature leads to blocking the transport of electrons from the primary acceptor to the secondary acceptors, which is expressed by a gradual disappearance of a slow component in the kinetics of p890+ reduction in the disappearance of a slow component in the kinetics of P890+ reduction in the darkness and by the intensification of a fast component resulting from the darkness and by the intensification of a fast component resulting from the interaction between the primary acceptor and P890+. Methodical aspects of absorption differential spectrophotometry of photosynthesizing organisms at low temperatures are discussed.

Bacteria↗
PubMed2002

Predatory prokaryotes: an emerging research opportunity.

Predatory prokaryotes have evolved a unique strategy of obtaining energy and biosynthetic materials from their surroundings: acquiring them from other living bacterial cells. These types of microbes have been found in a diverse variety of environments, and may play an important role in modulating microbial population structure and dynamics, as has been hypothesized for marine viruses and possibly protists. Only one genus of predatory bacterium, Bdellovibrio, has been extensively described and studied, though several other examples have been reported in the literature. In this review, the four basic strategies used by currently described predatory prokaryotes will be discussed: "wolfpack" group predation, epibiotic attachment, direct cytoplasmic invasion, and periplasmic invasion. Special adaptations to each approach will be considered, and compared overall to the genetic and biochemical characteristics of symbiotic or pathogenic prokaryotes living within eukaryotic cells. Two specific examples of predatory microbes, Bdellovibrio and Ensifer, will be described in terms of predation strategy, association with host cells, and host range. The prospects for bringing to bear the tools of molecular microbial genetics to the study of predatory prokaryotes will be explored, using current research with Bdellovibrio and Ensifer as examples.

Adaptation, Physiological↗