Home


For Cornell Faculty

Curriculum Resources

CSIP Publications

In the News

Education Standards

Related Links



Jennifer Mendell
2005 - 2006 CSIP Fellow

Research Interest:
Microbiology


I am a fourth year PhD candidate in the Department of Microbiology. My research focuses on a group of amazing bacteria that belong to the genus Epulopiscium. These intestinal symbionts of certain species of herbivorous surgeonfish are unusual in several ways. First, unlike a typical bacterium, such as E. coli, which reproduces through the process of binary fission, Epulopiscium has developed a novel mode of cellular propagation – the production of internal vegetative daughter cells. Another unusual characteristic of Epulopiscium is the amount of DNA found in Epulopiscium cells. On average an individual Epulopiscium cell contains 150 picograms of DNA! This is approximately 33,000 times the amount of DNA that comprises a chromosome from E. coli and 25 times the amount of DNA found in a human diploid cell! Finally, some types of Epulopiscium can reach lengths in excess of 0.6 mm and can easily be seen with the unaided eye! My research focuses on identifying cellular modifications which allow Epulopiscium to maintain such a large cell size.

Because the cells are so large, and Epulopiscium is non-pathogenic it can easily be brought into the classroom and serve as a model for studying basic concepts in microbiology, as well as helping to dispel the myth that bacteria are “primitive” or “simple bags of enzymes”. Microorganisms drive the biogeochemical cycles on our planet. I would like to develop an inquiry-based module that uses the symbiotic relationship of Epulopiscium and its herbivorous surgeonfish host to demonstrate the importance of these cycles in the maintenance of a healthy planet. Surgeonfish are keystone species on many tropical reefs. These fish graze on algae and it is believed that the Epulopiscium help the fish digest this complex vegetative matter. It has been demonstrated that in areas where the surgeonfish are over-harvested coral reef health is compromised. The algal overgrowth shades the coral leading to death of its photosynthetic symbiont and eventually to death of the coral. In addition to learning about the importance in biogeochemical cycling, students would gain an understanding of symbiosis, as well as an appreciation of the coral reef community, a very cool ecosystem!

As a CSIP Fellow I hope to build strong ties with educators in the community, learning from them the art of teaching and sharing with them my knowledge of microbiology. With a strong background in general biology, microbiology and anatomy and physiology I would feel comfortable in many different classroom settings and am more than willing to assist the teacher in any way I can, from developing new modules, updating previously existing modules or simply lending another set of hands. But for me the most important thing is to motivate and inspire students to learn science by asking, investigating, creating, discussing and reflecting!

 

 

Copyright 2006 CSIP, Cornell University