MBIO 3470 Lecture Notes - Lecture 15: Citric Acid Cycle, Gram-Positive Bacteria, Phylogenetics

• School: University of Manitoba
• Department: Microbiology
• Course: MBIO 3470
• Professor: Vladimir Yurkov

Document Summary

Using the distance method, woese classified the bacteria into 12 major phyla. These are the same phyla as determined by the binary association coefficients. In this case, we get a better idea of the evolutionary relatedness of the different phyletic groups. The next diagram shows the lineage of the extant organisms and the additive distances between organisms show the ed (evolutionary distance) between them. The sizes of the phyla vary: most are comprised of only a few species, while others are comprised of hundreds. The purple bacteria and the gram positive are among the largest and include the most of the bacteria we know. The deepest branching phyla of eubacteria (aquifex, thermatoga) are closest to the progenote and archaeae. Not surprising, they share several prominent characters with the sulfur dependent hyperthermophiles. This is the deepest branching group among the eubacteria: both are hyperthermophiles, optimal growth at ~85 degrees c.