Gregory Peter Krukonis
Specialization in ecology and evolution with a focus on bacteria and bacteriophages.
Teaching:
Bio 110 - Introduction to Cells and Molecules
Bio 113/114 - Introduction to Phage Biology/Phage Bioinformatics
Bio 361 Evolutionary Medicine
Bio 390 Ecology, Evolution, and Molecular Biology of Viruses
Research:
Bacteriophages, viruses that infect bacteria, are the most abundant life forms on the planet (an estimated 1031 phages exist at any moment). Still they are poorly characterized. My work focuses on characterizing the genetics, ecology, and evolution of bacteriophages of the soil bacterium, Bacillus subtilis. In particular, I am interested in understanding the factors that determine a phage’s host range (their ability to infect a few versus many bacterial strains) and how phages evolve as they exchange genetic material with other phages and as they encounter different bacterial strains to infect. These questions are both theoretically interesting (what factors determine whether a pathogen has a broad versus narrow host range?) and of practical importance (e.g., phages that are not likely to jump to new hosts may be better bets to control bacterial pathogens through “phage therapy”).
Many aspects of this research make it particularly attractive to undergraduate students. Kendra Hayden ’12 has isolated ten new phages that can infect Bacillus subtilis and we have determined that these phages vary in their host ranges; some phages can infect only a few strains of Bacillus subtilis (two or three out of the nine strains tested; these are phages with “narrow” host ranges), while others can infect most strains (at least six of the nine strains tested; phages with “broad” host ranges). We have sent out these phages’ DNA for sequencing and we are in various stages of assembling and finishing these genomes. Currently, we have three genomes basically finished (99.9% done) and have done preliminary genome annotation (using various programs to “call” genes and identify their functions) for two phages (work done with Katherine Boas ’16, Christina Cochran '13, Stacey Heaver ’15, Aden Lessiak ’15, and Brianne Tomko ’16).