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| ==Introduction==
| | Great topic!!! I thought your topic was very organized and easy to transition to the next section!! Maybe you could change the wording of your first sentence under Transfer of Electrons. I thought it was awkward the way you worded this sentence (Once the biofilm adhering the microbe to the metal is formed). Nice use of figures! Overall, your topic was very thorough and interesting! Good luck! |
| [[Image:PHIL_1181_lores.jpg|thumb|300px|right|<b>Figure 1. Shewanella onedensis MR-1 growing on hematite</b>. Shewanella are gram-negative, proteobacteria that are facultative anaerobes and can respire on a tremendous variety of inorganic and organic electron acceptors. One such electron acceptor is Fe<sub>2</sub>O<sub>3</sub>, which is commonly found in the clay hematite. (Photo from Oak Ridge National Laboratory; http://www.ornl.gov/info/ornlreview/v37_3_04/article02.shtml).]]
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| <br>The genus Shewanella consists of gram-negative proteobacteria that are typically rod shaped, 2-3 μm in length and 0.4-0.7 μm in diameter (Fig 1). These facultative anaerobes are often found in marine sediments, and can swim with the aid of a single polar flagellum (Venkateswaran et al., 1999). Since the modern characterization Shewanella in 1988, DNA:DNA hybridization and 16S rRNA sequencing has been used to identify more than 40 distinct species. The features that characterize this genus include psychrotolerance, mild halophilicity, and the capacity to reduce an unparalleled array of inorganic and organic compounds for respiration (Gralnick et al., 2007). Their capacity to respire on various metals as well as their production of endogenous hydrocarobons has ignited tremendous interest in the characterization and potential applications of these microorganisms. <br>
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| ==Brief History==
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| <br>Shewanella was originally identified in 1931 as one of multiple species of bacteria growing on putrid butter (Hammer, 1931). It was first classified as part of the genus Achromobacter and was reclassified multiple times on the basis of its polar flagella, its status as a non-fermentive marine bacteria, and the guanine/ cystine content (% GC) of its DNA (Gralnick et al., 2007). In 1985, 5S rRNA sequencing was used support an entirely new name for the genus, Shewanella. The name was given as a tribute to Dr. James M. Shewan for his work in fisheries microbiology (MacDonell et al., 1985).<br>
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| ===Model Species of the Genus Shewanella: <i>Shewanella oneidensis MR-1</i>===
| | This was really interesting and well written. I learned a lot from reading it! I did catch some small edits that you need to do. |
| <br>In 1988, a group of scientists became curious about the unexplained levels of reduced manganese (Mn<sup>2+</sup>) present in New York’s largest freshwater lake, Lake Oneida (Fig 2). In nature, manganese generally exists in its oxidized form (Mn<sup>4+</sup>), and thus the scientists hypothesized that some biological process was reducing the manganese. Upon experimentation, they discovered a species of <i>Shewanella</i> that respires by transferring electrons to Mn<sup>4+</sup>. Interestingly, oxidized manganese is insoluble, which indicated that the bacteria have a way to transfer electrons to metal outside of their cells for respiration. After rRNA sequencing, the bacteria was characterized as a <i>Shewanella </i>, and the species was named <i>Shewanella oneidensis</i> MR-1 (“manganese reducer”) after the lake in which it was discovered (Slonczewski et al, 2011). This MR-1 species was the first <i>Shewanella</i> to genome to be sequenced, and thus it has become a model system for the study of the genus (Gralnick et al., 2007). <br>
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| ==Section 2==
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| <br>Include some current research in each topic, with at least one figure showing data.<br>
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| ==Section 3==
| | Shewanella needs to be capitalized and italicized in the following areas: |
| <br>Include some current research in each topic, with at least one figure showing data.<br>
| | -Last sentence of "Model Species..." section |
| | | -In the first paragraph of the "Mechanism of Action..." section, in the second sentence |
| ==Conclusion==
| | -Figure 14 caption |
| <br>Overall paper length should be 3,000 words, with at least 3 figures.<br>
| | -Figure 15 caption |
| | | -Figure 16 caption |
| ==References==
| | -"Using Shewanella hydrocarbons" section, 2nd sentence |
| [Sample reference] [http://ijs.sgmjournals.org/cgi/reprint/50/2/489 Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "''Palaeococcus ferrophilus'' gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". ''International Journal of Systematic and Evolutionary Microbiology''. 2000. Volume 50. p. 489-500.]
| | -"Using Shewanella hydrocarbons" section, 3rd sentence |
| | | -"Using Shewanella hydrocarbons" section, 5th sentence |
| Edited by student of [mailto:slonczewski@kenyon.edu Joan Slonczewski] for [http://biology.kenyon.edu/courses/biol238/biol238syl09.html BIOL 238 Microbiology], 2009, [http://www.kenyon.edu/index.xml Kenyon College].
| | -"Using Shewanella hydrocarbons" section, 6th sentence |
| | | -"Using Shewanella hydrocarbons" section, 7th sentence |
| <!--Do not edit or remove this line-->[[Category:Pages edited by students of Joan Slonczewski at Kenyon College]]
| | -"Using Shewanella hydrocarbons" section, 8th sentence |
| | -"Using Shewanella hydrocarbons" section, 2nd paragraph |
Great topic!!! I thought your topic was very organized and easy to transition to the next section!! Maybe you could change the wording of your first sentence under Transfer of Electrons. I thought it was awkward the way you worded this sentence (Once the biofilm adhering the microbe to the metal is formed). Nice use of figures! Overall, your topic was very thorough and interesting! Good luck!
This was really interesting and well written. I learned a lot from reading it! I did catch some small edits that you need to do.
Shewanella needs to be capitalized and italicized in the following areas:
-Last sentence of "Model Species..." section
-In the first paragraph of the "Mechanism of Action..." section, in the second sentence
-Figure 14 caption
-Figure 15 caption
-Figure 16 caption
-"Using Shewanella hydrocarbons" section, 2nd sentence
-"Using Shewanella hydrocarbons" section, 3rd sentence
-"Using Shewanella hydrocarbons" section, 5th sentence
-"Using Shewanella hydrocarbons" section, 6th sentence
-"Using Shewanella hydrocarbons" section, 7th sentence
-"Using Shewanella hydrocarbons" section, 8th sentence
-"Using Shewanella hydrocarbons" section, 2nd paragraph
