This investigative case module was prepared as part of a BioQUEST faculty development workshop. The cases, resources, and implementation strategies were developed by participants for use with their own students. We invite you to adopt and adapt the following materials.

The BioQUEST Curriculum Consortium is committed to the reform of undergraduate biology instruction through an emphasis on engaging students in realistic scientific practices. This approach is sometimes characterized as an inquiry driven approach and is captured in BioQUEST's three P's (problem-posing, problem-solving, and peer-persuasion). As part of this workshop groups of faculty were encouraged to initiate innovative curricular projects. We are sharing these works in progress in the hope that they will stimulate further exploration, collaboration and development. Please see the following links for additional information:

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Investigative Cases
The Case: Bacterial Polygamy

Damien and Samantha both work with the Centers for Disease Control (CDC) where they work on surveillance of staphylococcal outbreaks in the greater Atlanta area. Routinely, they pickup samples from various hospitals.

Both individuals had just returned to work after a car accident in which both suffered severe cuts and bruises. Regular hospital pickups of staphylococcal samples were delivered to the lab on Monday by the courier. Damien and Samantha processed the samples as usual. Later that week, both lab mates became very ill and were diagnosed with staphylococcal infections. Both were given methicillin, an antibiotic commonly used to treat Staphylococcal infections.

Within days, Samantha was feeling much better. Damien, however, was getting worse and not responding to the medication.

Case Author:
Karita Ambrose Emory University:Center for Science Education
Daniel Williams Emory University:Center for Science Education

Case Analysis

Physical condition of the patients

Exposure to samples

Hospital examination

Opportunistic infections

Differences in response to treatment

Option: Include a know / need to know chart like the one below:

What do you know?
What do you need to know?

Learning Goals


Develop an understanding of bacterial pathogenesis and the steps involved

Host/microbe interaction

Factors that contribute to virulence

An understanding of gene acquisition



Investigations and Activities

Students will be divided into groups and prepare poster presentations and a one page report (individually) on a pathogen (given by the instructor) using an article from a scientific journal and newspaper, as well as a website. The student will discuss characteristics of the pathogen and compare the writing styles, technicalities, and scientific merit of the articles

Lab Activities
Determine Methicillin minimum inhibitory concentrations (MIC) of Staphylococcal isolates

Students will do restriction fragment length polymorphism (RFLP) analysis

Schematic representation of RFLP



Textbook: Microbiology, Fifth Edition, Lansin M. Prescott, John P. Harley, and Donald A. Klein, McGraw-Hill Companies, Inc., 2002 ISBN 0-07-112259-1

Scientific Journals: Science, Scientific American, Journal of Infectious Diseases

Students will usually obtain additional references or resources
to help answer or explore their questions.

Special Data Items

1. bact.jpg
2. mic.jpg
3. rflp.jpg
4. conj.jpg


Student Products

Students will do group posters and write individual 1-2 page critiques. For laboratory activities, students will write a report describing their results

Students will have the opportunity to participate in classroom interactive programs (BioQUEST\Microbial GCK) describing gene acquisition and antibiotic resistance

Assessment and Evaluation Plan

Poster presentation students should learn to collaborate with peers and will be evaluated collectively as a group by their peers and the instructor

Students will be expected to learn about a particular bacterial pathogen and known factors related to its virulence

For writing assessment, students should be able to review and critique the articles used in the group poster presentation.



Course name:
Microbiology (Bio 233)
Likely sequence in syllabus:
Microbial Diseases and Their Control
Time during term:
Second half of the course
2 weeks
Lecture and lab
Students in course:
Sophomore/junior majors
Collaborative elements:
Group Activities; Resource assessment; In-class and out of class discussions
Additional notes:




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