Bacteriophages as Teachers

ANNA CASTANO, REBECCA OOT, SHAWNTE FERMAHIN, CARA FINK, JESSICA DAHL, MARSHALL THOMAS, TAKEHIRO YABANA, CARLY ALLEN, JOE JARDINE, TODD CALLAWAY, RAUL RAYA, ELIZABETH KUTTER, ANDREW BRABBAN

Atlanta, Georgia, USA

Congreso; 2005 General Meeting American Society for Microbiology; 2005

American Society for Microbiology, USA

Bacteriophages offer an unparalleled tool for teaching microbial physiology and ecology, as well as critical thinking and the techniques of molecular biology to students at all levels. At Evergreen, various projects related to potential therapeutic applications of phage have added special incentive, drawing students from many backgrounds to apply classroom knowledge to practical hands-on experiences in the laboratory. For example, ongoing collaborative research with the USDA (College Station, TX) to develop an effective strategy to control Escherichia coli O157:H7 has led to the isolation of 49 new phages from the feces of cattle in feed lot stock pens. Ten of these phages, now known as CBA phages, were chosen for further study based on their high EOP on O157:H7 strains and were distributed to students new to the research team whose training would primarily consist of the characterization and purification of their designated phage. This required the students to learn and apply techniques and skills from basic aseptic practice and making media, to advanced molecular methods. After purifying their individual phages by repeated single-plaque isolation, students determined optimal conditions for phage growth, preparation of phage stocks, host-range analysis and genome size determination using Pulse Field Gel Electrophoresis (PFGE). The students have done repeated infection experiments under various growth conditions relevant to potential applications; their intriguing results have helped toexpand our understanding of the phage infection process under real-world conditions. Analysis ofrestriction fragments, as well as PCR using primers from highly conserved regions of known phage families are helping to compare these phages with phages that have already been sequenced. Students can play an important role in exploring the properties of a myriad of new, interesting and potentially useful phages while honing their research and analytical skills and developing an enthusiasm for science.