Enrichment Culture ~ Honors Project--Spring
Enrichment Culture is defined by Thomas Brock in the textbook Brock,
Biology of Microorganisms, as "Use of selective culture media and incubation
conditions to isolate microorganisms directly from nature." Thomas
Brock is responsible for isolating Thermus aquaticus from hot springs
in Yellowstone Park. From Thermus aquaticus scientists isolated
the Taq polymerase which is used in Polymerase Chain Reaction.
Design and implement an enrichment scheme to isolate an organism of
Choosing a project:
Write a step by step protocol for the isolation of your organism.
Share your research on enrichment and your protocol design
with your peers via a poster session and with the scientific community
via a virtual poster session on the world wide web.
Read about the diversity of bacteria. Choose an organism with
This is a group project and students in the
group will work together in lab and on required research and writings.
Read to determine the ecology of the organism. Can you easily
sample for the organism?
Read about culture conditions and consider enrichment conditions.
Can you easily enrich for and grow the organism?
If the answers to these two questions is "Yes". Find a partner
who is similarly interested in the project and begin!
Each student, however, should keep their own lab notebook and record
their own observations.
The Honors project has five phases:
The group may find it necessary on occasion, to work outside
scheduled lab times. Students should consider schedules when choosing
One grade will be given to the group for the project.
1. Background reading. What is enrichment culture?
Instructions for Data Presentation:
Determine the significance of C. B. van Niel Beijerinck and Sergei
Winogradsky with respect to enrichment methods.
2. Library research and definition of initial hypothesis for enrichment.
Refer to your text and library references to gain background
material needed for protocol design. Determine the source of the microbe.
Consider the environment where your organism is found. Identify conditions
that would selectively support the growth of your organism. Consider
the use of selective and enriched media. Determine environmental
conditions needed to support the growth of your organism. Identify
characteristics of your organism, that will allow identification of your
organism in the background of other organisms, that may also survive your
enrichment conditions. Research the ecological role of your organism.
Identify any interesting products produced or reactions performed by your
organism. Identify why your microbe merits further study. Determine
characteristics (morphology, physiology, ecology)of your organism.
3. Submit an initial research plan that you will follow
to test your hypothesis.
References on reserve that may be helpful:
Bergey's Manual of Systematic Bacteriology
Bergey's Manual of Determinative Bacteriology
The Prokaryotes, Starr, Stolp, Truper, Balows, Schlegel, editors.
Handbook of Microbiological Media, Atlas
Brock, Biology of Microorganisms, Madigan, Martinko and Parker
Methods for General and Molecular Bacteriology, Gerhardt, Murray, Wood,
From your reading, hypothesize how you may isolate your organism
of interest and how you will identify that you have successfully isolated
The initial plan must be well thought out and detailed
(including all materials and media needed).
4. Laboratory Research
The initial plab must include steps to:
Enrich for the organism.
The research plan must clearly list requirements and media constituents
needed to accomplish each step.
Isolate the organism in pure culture.
Identify the genus of your organism.
Maintain the growth of the organism.
In lab you will test your enrichement culture hypothesis according
to the steps in your plan.
5. Formal Presentation of Data and Development of Protocol
As you work, you may find that some steps need to be amended, and that
addtional materials are needed.
Order additional materials by submitting a written request to your instructor
or TA in one lab prior.
Note: You will be making your own media, incubating your own cultures,
and watching all time requirements for incubation etc.
Record all observations and protocol changes in a lab notebook.
Data will be presented via a Poster session/ web page. See
From your data, you are to generate a protocol that could be used by others
to enrich for, and isolate a pure culture of the organism that you studied.
The final protocol should be typed and submitted on the day of your oral
poster presentation. The text of the protocol should be a part of
your web page.
Researchers present their work to colleagues in a variety of formats.
For this assignment, your work will be presented through a virtual
poster session and an oral presentation of the on-line poster.
In addition, you will provide a product appropriate for
Formal oral presentations
Peer-reviewed publication of work in scientific journals.
A lab manual-type protocol
that will outline the steps to enrich for and isolate your organism.
The Poster will give the HIGHLIGHTS of your project.
The content should presented succinctly
Well labeled diagrams and tables can substitute for paragraphs of dialog.
Sections should be written in second person and in past tense. You
are presenting what you have done.
Refer to a research article in Science.
The Oral Presentation of Poster~
Give your names and section number.
Describe the rationale of your enrichment culture approach. Why
was it expected to be successful?
Provide steps used in isolation(Use a diagram or flow chart.)
Indicate use of special media or environmental conditions.
List constituents of media.
Present steps used to confirm identity of organism of interest.
Provide support for the success of your approach.
Give raw data in tables and drawings, using figure legends to give textual
Highlight important characteristics (morphology and physiology) that were
used to identify your organism.
Present data regarding production of product and identification of organism.
Include a statement of data interpretation. Did you prove your hypothesis?
Were you successful in isolating your organism from the enrichment method
that you outlined? Were your observations consistent
with expectations? Did you need to alter your original enrichment
method? Give explanations.
Highlight how you knew, from your data, that you isolated the organism
Describe the ecological role of your organism.
Highlight any interesting characteristics.
Stress the significance of the isolation of your organism (clinical significance?
significance to ecology of our planet, significance in that a process or
product can be used for biotechnology?) Why is it important to have
a clear step by step method (your protocol) to isolate this organism?
Present a short paragraph that summarizes the highlights of your
References should include at least one resource book and one journal article.
Posters will be presented at a Poster Session. Each group will
present their virutal poster including a detailed discusion
of techniques used in isolation, specific characterisitics of the
microbe isolated, and its significance. Material presented will make
up questions on the Lab Final exam.
The Final Protocol~
This is a product of your enrichment culture research.
The protocol must give step by step directions that will lead to the
isolation of a pure culture of your organism from an environmental sample.
It must include detailed materials and methods.
Use the same information that was presented in your poster. Just
reformat for the Web!
Links to Summary, Introduction, Method, Results, Discussion, References,
Final Enrichment Protocol.
An image of your organism growingin pure culture.
An image of your organism as seen under the microscope.
Links relating to
Enrichment culture methods.
Ecology of your organism.
Significance of the study of your organism