Can Prokaryotes Evolve Rapidly in Response to Stimuli pp

Can Prokaryotes Evolve Rapidly in Response to Environmental change?: 

Can Prokaryotes Evolve Rapidly in Response to Environmental change? By Christopher Salazar

Causes of Evolution in Bacteria: 

There are three factors Rapid reproduction High mutation rate Horizontal gene transfer Causes of Evolution in Bacteria

Prokaryotes and the Tree of Life: 

The phylogenic Tree of Life provides the evolutionary relationships of organisms Organisms are classified based upon molecular and morphological data Prokaryotes and the Tree of Life

Horizontal Gene Transfer: 

There are problems within the Tree of Life model, especially in regards to prokaryotes. Prokaryotes are able to exchange genes with distant species. This process is known as horizontal gene transfer. Horizontal Gene Transfer

Experiment: 

Goal Assess how the Tree of Life model has suffered from artificial effects in estimating the gene content of ancestral species 160 prokaryotic species Algorithm put into place to minimize problems with estimations of gene content of the organisms. Rapid evolution resulted from massive gene group transfers which create evolutionary pathways via horizontal gene transfer Experiment

Slide 7: 

The algorithm adopted from a previous experiment by another scientist has been used to effectively estimate gene-context evolutionary history. This model estimates the rate of gene gain and loss throughout an individual evolutionary history. This general diagram refers to all 160 prokaryotic species.

Slide 8: 

The most obvious gene rates and loss are estimated along the branches.

Slide 9: 

The rates mentioned before will offer the simplest phylogenetic tree.

Slide 10: 

The final diagram reveals the six gene groups and the pathway they have undergone. The ancestral species are accurately put into place and we can identify the shared derived characteristics. Although artificial effects have been accounted for, the phylogenetic tree reveals some weak ties among the organisms through molecular data.

Slide 11: 

The linear line, labeled Gradual Acquisition, reveals the gene groups that were attained by the linear phylogenetic tree. The arced lined labeled Rapid Acquisition account for HGT.

Slide 12: 

It should be noted that the graph also reveals prokaryotes do not acquire individual genes, but rather groups that work well together. By the data collected, HGT facilitates rapid evolution in prokaryotes.

Conclusion: 

Four major findings Pathways of the phylogenetic tree is based on the emphasis of favorable traits. Acquisition of groups of genes that function well together are promoted Rapid evolution is due to horizontal gene transfer These pathways have occurred more recently than previously believed. Conclusion

Response to Stimuli: 

Rapid evolution is facilitated when there is great stress on the environment. For example, antibiotics and other drugs that are created to eliminate bactera either within the body or some external environment. Response to Stimuli