Post by skytroll on Jul 25, 2008 2:21:44 GMT -5
This talks of the forced adaptation that has happened in the
wild.
Why Sequence Rhodobacter sphaeroides?
How can a photosynthetic bacterium help us understand a fundamental question in evolutionary biology? ..........................................................................................The acquisition and loss of genetic information permits the adaptation of an organism to an ever-changing environment. However, this genetic flux is a double-edged sword. On the one hand, it permits the acquisition of new adaptive traits, but this process may result in the damage or loss of functioning genetic systems, with possibly dire consequences for the individual or species. How can such genomic plasticity occur without being severely disruptive to the ongoing lifestyle of an organism? One possible solution to this dilemma is the presence of genomic “safe zones,” where the insertion or deletion of DNA is not disruptive to the genome at large. Such safe zones may also provide a “molecular workshop,” where genetic tinkering may permit the evolution of novel traits to meet the demands of environmental change. ..........................................................................................The photoheterotrophic bacterium Rhodobacter sphaeroides possesses two chromosomes, one of which contains a high density of information content. The second, chromosome II, has a much lower coding density and could serve as a reservoir for the exchanges and manipulations described above. This hypothesis will be tested by sequence comparisons of chromosome II from six to ten different isolates of Rhodobacter sphaeroides. Researchers will be looking for genetic content differences between these chromosomes. Such differences may include the relative numbers and types of essential and nonessential genes, the age of genes (i.e., recently acquired vs. more ancient genes), breakpoints where genetic exchanges occur, and a mechanism by which these exchanges could take place. These findings should relate directly to the origin and evolution of the microbial genome and are likely to have mechanistic implications for the evolution of the eukaryotic cell.
CSP project participants: Samuel Kaplan (proposer, Univ. of Texas Med. School, Houston) and Timothy J. Donohue (proposer, Univ. of Wisconsin-Madison).
www.jgi.doe.gov/sequencing/why/52075.html
Here is what they look like:
LIL SISSY. the caretenoids.........biosynthesis.
Mr. Darrah said these were segmented:
But these are involved with the red algae.
and I bet the dunaliella......rhodopsins.
The bacteria that could work but as photosynthesis,
not by bioluminescence.......mmmmmm
"
Rhodobacter sphaeroides 2.4.1, is a facultative photosynthetic member of the a-3 subgroup of Proteobacteria.
.................................................................................................... In terms of the structural and functional aspects of the light reactions of photosynthesis it is undoubtedly the best studied of all photosynthetic systems. It is also the subject of intensive investigations worldwide on the structure, function and regulation of its photosynthetic membranes, its mechanisms of CO2 fixation, nitrogen fixation, cytochrome diversity and electron transport systems. .........................................................................................Crystallization of the photosynthetic reaction center and the application of site-directed mutagenesis is providing fundamental insights into light driven, renewable energy production. Individually and in combination, these areas have been and will continue to be major areas of interest to the DOE.
In addition, R. sphaeroides has been shown to be able to detoxify a number of metal oxides and oxyanions and is the subject of ongoing studies in this area, in keeping with the direct mission of the DOE in bioremediation. Additional investigations over many years have led to increased knowledge of tetrapyrrole and carotenoid biosynthesis, which have broad applicability.
This organism is also the first known free-living bacterium to be able to utilize the regulatory systems associated with.......................................................................................................... Quorum-Sensing....................... to reversibly initiate the development of a community growth form, perhaps associated with biofilm formation, and a dispersed growth mode, depending upon the quality of the growth medium. These studies are of critical concern to studies of bioremediation and biotechnology. Other very recent studies revealing how an electron transport chain can "communicate" with a variety of genetic elements has led to the development of a new paradigm for gene regulation."
genome.jgi-psf.org/finished_microbes/rhosp/rhosp.home.html
That would be the electron transport chain,
These do not die. They eat metal, radiation etc.
Skytroll
wild.
Why Sequence Rhodobacter sphaeroides?
How can a photosynthetic bacterium help us understand a fundamental question in evolutionary biology? ..........................................................................................The acquisition and loss of genetic information permits the adaptation of an organism to an ever-changing environment. However, this genetic flux is a double-edged sword. On the one hand, it permits the acquisition of new adaptive traits, but this process may result in the damage or loss of functioning genetic systems, with possibly dire consequences for the individual or species. How can such genomic plasticity occur without being severely disruptive to the ongoing lifestyle of an organism? One possible solution to this dilemma is the presence of genomic “safe zones,” where the insertion or deletion of DNA is not disruptive to the genome at large. Such safe zones may also provide a “molecular workshop,” where genetic tinkering may permit the evolution of novel traits to meet the demands of environmental change. ..........................................................................................The photoheterotrophic bacterium Rhodobacter sphaeroides possesses two chromosomes, one of which contains a high density of information content. The second, chromosome II, has a much lower coding density and could serve as a reservoir for the exchanges and manipulations described above. This hypothesis will be tested by sequence comparisons of chromosome II from six to ten different isolates of Rhodobacter sphaeroides. Researchers will be looking for genetic content differences between these chromosomes. Such differences may include the relative numbers and types of essential and nonessential genes, the age of genes (i.e., recently acquired vs. more ancient genes), breakpoints where genetic exchanges occur, and a mechanism by which these exchanges could take place. These findings should relate directly to the origin and evolution of the microbial genome and are likely to have mechanistic implications for the evolution of the eukaryotic cell.
CSP project participants: Samuel Kaplan (proposer, Univ. of Texas Med. School, Houston) and Timothy J. Donohue (proposer, Univ. of Wisconsin-Madison).
www.jgi.doe.gov/sequencing/why/52075.html
Here is what they look like:
LIL SISSY. the caretenoids.........biosynthesis.
Mr. Darrah said these were segmented:
But these are involved with the red algae.
and I bet the dunaliella......rhodopsins.
The bacteria that could work but as photosynthesis,
not by bioluminescence.......mmmmmm
"
Rhodobacter sphaeroides 2.4.1, is a facultative photosynthetic member of the a-3 subgroup of Proteobacteria.
.................................................................................................... In terms of the structural and functional aspects of the light reactions of photosynthesis it is undoubtedly the best studied of all photosynthetic systems. It is also the subject of intensive investigations worldwide on the structure, function and regulation of its photosynthetic membranes, its mechanisms of CO2 fixation, nitrogen fixation, cytochrome diversity and electron transport systems. .........................................................................................Crystallization of the photosynthetic reaction center and the application of site-directed mutagenesis is providing fundamental insights into light driven, renewable energy production. Individually and in combination, these areas have been and will continue to be major areas of interest to the DOE.
In addition, R. sphaeroides has been shown to be able to detoxify a number of metal oxides and oxyanions and is the subject of ongoing studies in this area, in keeping with the direct mission of the DOE in bioremediation. Additional investigations over many years have led to increased knowledge of tetrapyrrole and carotenoid biosynthesis, which have broad applicability.
This organism is also the first known free-living bacterium to be able to utilize the regulatory systems associated with.......................................................................................................... Quorum-Sensing....................... to reversibly initiate the development of a community growth form, perhaps associated with biofilm formation, and a dispersed growth mode, depending upon the quality of the growth medium. These studies are of critical concern to studies of bioremediation and biotechnology. Other very recent studies revealing how an electron transport chain can "communicate" with a variety of genetic elements has led to the development of a new paradigm for gene regulation."
genome.jgi-psf.org/finished_microbes/rhosp/rhosp.home.html
That would be the electron transport chain,
These do not die. They eat metal, radiation etc.
Skytroll