Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

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Unit Chapters
Genomics
Proteins & Proteomics
Evolution & Phylogenetics
Microbial Diversity
Introduction
Microbes as the First Organisms
The Diversity of Microbial Metabolism
Archaea and Bacteria
The Universal Tree of Life
Studying Unculturable Microbes with PCR
Microbes and the Carbon Cycle
Microbes and the Cycling of Nitrogen
Biofilms
Biofilms Formation and Bacterial Communication
Impact of Biofilms on Humans
Communication Between Bacteria and Eukaryotes
Microbes in Mines
Microbial Leaching of Ores
Coda
Emerging Infectious Diseases
HIV & AIDS
Genetics of Development
Cell Biology & Cancer
Human Evolution
Neurobiology
Biology of Sex & Gender
Biodiversity
Genetically Modified Organisms
Communication Between Bacteria and Eukaryotes

Bacteria also communicate with plants and animals. One striking example involves the Rhizobium bacterium, which helps fix nitrogen for legumes (such as pea and clover plants). This bacterium colonizes root hairs in specialized nodules built by the plant. Before the plant and bacteria ever come into contact, they are communicating. The plant sends out chemical signals,
Figure 8a. Euprymna scolopes
known as flavonoids, which penetrate Rhizobium cells and stimulate a gene-activating protein. The protein then switches on bacterial genes so that other proteins, such as Nod factor, are produced. Nod then stimulates the plant to form nodules.

Another example is the signaling between the luminous bacterium Vibrio fischeri and its host, the squid Eupryman scolopes. These bacteria colonize a specialized light organ on the squid, providing camouflage. The squid is a nocturnal forager;
Figure 8b. Light organ of Euprymna scolopes
luminescence from the bacteria erases the shadow that would normally be cast from above by the moon's rays. Quorum sensing molecules allow the bacteria to turn on light production only when the colony has reached adequate density. However, the bacteria do not just communicate with one another - their chemical signals spur maturation of the light organ. Hatchling squid raised in sterile seawater do not develop the pouch that eventually houses the bacteria.

Like the Dr. Doolittle of fiction, who had the remarkable ability to talk with animals, scientists of the future will be continuing studies into the language of microbes.

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