BISC209/S13: Assignment 209 Lab8

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Wellesley College-BISC 209 Microbiology -Spring 2013


Lab 8: Isolate Tables and Figures providing evidence of structural and functional diversity and evidence of co-operation and competitive behavior

Graded Assignment:

Before the end of today's lab, be sure to complete the google doc for your site adding all your data and any new data from your isolates. Post any photos you have taken in your sampling site folder. Your lab partners need this information to complete this assignment successfully.

Do as much of table and figure preparation as well as writing, as a group, as you can while in lab. Every group (site) will be preparing one google document and the other two groups (sites) are responsible to read and comment on that document prior to next lab (edit: each person should add comments followed by their group and initials, e.g. A_VR). The grade will be calculated both on the quality of the document you put together as a group, as well as the individual comments you provide to other groups. This means that you will lose points if you do not provide comments. This document will be a starting point for your results in your final paper.

Goal: Is there evidence for structural and metabolic diversity and cooperation and competition among these members of our soil community?

Use the isolate tests data Google doc for your sample site to construct a concise Table for your final paper (your isolates and your teammates' isolates from the same sampling site) and write a complete results narrative. You should include in the table: The isolate ID you used all semester, Gram stain, description of the colony morphology, description of the individual bacteria's structural characteristics including shape & arrangement (cocci, rods, with descriptors ie., large, small, bullet shaped, in chains, etc.), evidence of spores (either endospore stain positive or visualization of empty areas in vegetative cells on Gram stain), motility, etc. Include test results that you will use as evidence for metabolic diversity or community behavior, ie. nitrogen cycling capabilities, fermentation of lactose, mannitol, etc. Be sure to add your Isolate ID from GeneWiz.

Goal: "Is there evidence of communication between and interactions among the bacteria isolated from your soil community?"

Design figures and result analyses for examples of isolate competition and co-operation using the antibiotic assays (if any of your site teammates indicated the presence of an antibiotic producer) and interactions assay. A good figure will use an annotated photograph of those plates, work with ALL of your sampling sites' interaction assays on this results section but you will want to select the best image for the figure, annotate it, and limit yourself to 1-3 examples of both co-operation and competition. An annotated photo of any positive antibiotic producers from your sampling site will make your analysis more useful for a reader that was not in our lab. If your site had no positive antibiotic producers, you can include this test, its negative results, and analysis in your isolate table without an additional figure.

Writing tip: The results analysis narrative for the table of tests performed on the isolates might start out, "In order to show structural and metabolic diversity as well as the potential for community behavior (co-operation and/or competition) among members of a soil community (the goal), nitrogen cycling bacteria & spore-forming bacteria were enriched and selected using media and protocols described in Materials and Methods. Once in pure culture a few soil community members of these groups and other interesting bacteria isolated on non-selective media were visualized using staining techniques for cell wall structure in a Gram stain, production of endospores with Shaeffer-Fulton endospore stain. Additionally motility testing was performed on each isolate using soft agar deeps (the tools). Evidence for a role in the nitrogen cycle was assessed by________. (continue to describe any other testing you include in your table)......" Of couse where and how you use these data depends on the way you are planning to tell the story of this semesters work. So the writing tip is a suggestion of one possible approach. The most important aspect of your final paper is that your "story" is well told and complete. Were your goals successfully met?