The Biotechnology Project: Proteins

Now that the project is completed, it is time to write the project report. Due to the length of time spent on this project, writing the report may seem an overwhelming task. Remember that no matter how well the purification project worked, and even if it disintegrated into total chaos, you can still write an excellent report.

You will be working in pairs or groups to present your oral reports but you will prepare your written reports individually. The instructor will provide you with guidelines for your oral reports. A suggested format for the written report follows.

Note: Generally we prefer to have oral presentations first, then allow about a week before final written reports are due. The oral reports allow for discussion, analysis and comparison between groups of results and that information can be used to write the discussion section of the written report.

Suggestions For Written Reports: The written report should be organized into four distinct, non-overlapping sections as follows:

Introduction. The introduction gives the background to the project,
starting with the most general statement of the project goals, leading up to more specific information such as the types of separation procedures that will be used and which assay methods will be used for analysis. This section should be one-two pages long. No recipes or technical details are given in this section.
Materials and Methods. Due to the length of this project, this section should be organized into subsections; for example, extraction, salting out, ion exchange chromatography, Western Blotting and so on. You should report the methods that you performed in past tense and in third person. You should state exactly how you did them, not how they are written in the lab manual. Do not make a list of the methods - they should be written out in paragraph form. The purpose of this section is to permit someone who is not familiar with the project to repeat all of the procedures exactly as you carried them out. You may assume that your reader is familiar with the laboratory and does not have to be told such information as the fact that you turned the spectrophotometer on in order to use it.
Results. The most common error for a results section is to string together tables and graphs without text explanations. First, organize all the data and assemble all the tables and graphs (part A). Then explain them to your reader (a knowledgeable someone who wasn't in the lab with you).
- Tables and Graphs:
  
  You need at least three tables. Each table must have a title and a legend. The legend, or caption, should explain the table and include any notes necessary to understand your data. A sample calculation must be included for each type of calculation.
  - Enzyme assay table
  - Protein assay table
    Include a sample standard curve
    
    You need to include the raw data from each assay that you did if you used the information from that assay in the project. But if you protein assay and did another one, you do not need to report that one. However, the protein assay should be in your notebook, but it can have a large X through it, to indicate that you did not use the data. Explain in your notebook why you did not use that data.
  - Summary table showing Specific Activity and Yield Data. You need a table that includes the following data for each step of the purification: (see Table 4.2 in chaper 4).
    - total protein in µg or mg
    - total enzyme activity in units
    - specific activity
    - percent yield
    - purification factor
  - Ion Exchange Chromatography Data. You need a properly labeled graph that shows the relationship between enzyme activity and A₂₈₀ as well as fraction number. Use a double Y axis to include both functions. Indicate which fractions were pooled for further analysis. Don’t forget the title and legend.
  - PAGE and Western Blot Data. You need some sort of diagram, photo, drawing, photocopy or other visual representation of your dried gels and Western. Make sure that you label all of the lanes and remember to include a title and legend for each figure. Normally photographs of gels and Westerns are presented in papers.
- Text Explanations of Results. You must make statements about the Results. Describe the overall results, not each separate measurement. Look at the data in the tables and graphs and decide what they communicate about the project. Then state in words what that information is. For example, the statement might go something like this "As shown in Figure 5 (Ion exchange graph) the peaks of protein elution were at fractions 20-25 and 45-55. Both of these protein peaks were peaks of ß-galactosidase activity, as demonstrated by enzyme assay results, although peak 20-25 had considerably more enzyme activity than peak 45-55. "
  Graphs and tables present data- they do not state results so do NOT simply say "The data is present in Table X and Graph Z."
  
  The results should state only what you found, not how it would have been better if only ....... That kind of speculation is for the Discussion section
DISCUSSION

A brief summary of your results.
A complete discussion of each section of your results. For example, you might discuss the possible reasons for a decrease in yield at a particular step. Did your specific activity increase as the purification proceeded? Did the total enzyme activity go up or down? You might discuss why you chose to pool the particular fractions you pooled. You might speculate on how you would make different decisions if your goals were different or if your previous purification step(s) had turned out differently.
A discussion of similarities and differences in procedures followed and results obtained between your group and other groups or individuals. This information will be available to you during the oral presentations. Be prepared to ask questions when your fellow students are presenting.
A discussions of various aspects of the protocols. Describe ways you would change the protocols and why you think the change would be an improvement. Speculate on improvements you would make if you were to repeat this project.
A description of what you learned about how proteins are isolated and purified. Be specific about the important concepts of protein purification and how different strategies can be used to isolate different proteins. For example, include different methods of extraction, different kinds column chromatography that might be appropriate for purifying various proteins.
A discussion of any other results you might have. Did you compare the activity of a frozen aliquot with a refrigerated one?
Conclusions

Chapter 6: Reports

Chapter 6:
Reports