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Date Submitted

Spring 4-29-2014

Research Mentor and Department

Dr. Sarah CR Elgin




There are an estimated 1031 species of bacteriophages in the Earth’s biome. As a result, understanding the immense diversity of bacteriophages is a topic of great interest. We isolated a novel mycobacteriophage, called Gaius, from soil collected near the Watershed Nature Center in Edwardsville, IL. We enriched our soil sample using Mycobacterium smegmatis, and after purification, its plaque morphology was characteristic of a temperate phage. Following purification, we used electron microscope imaging to find Gaius’ physical structure to be similar to other members of the A4 subcluster. We sequenced Gaius’ genome using the Pacific Biosystems Sequencing technique, making Gaius one of the first phages sequenced using this technique. This provided adequate information to definitively classify Gaius into the phage subcluster A4 with a genome length of approximately 51.37 kbp. While analyzing the sequence, we made gene calls for 86 genes that appeared to be present within Gaius’ genome. We utilized BLAST, HHPRED, and Phamerator programs in order to determine gene functions. Using these programs, we were able to assign functions to a significant percentage of Gaius’ genes due to its high similarity to other previously annotated A4 phages and strong BLAST alignment results. The accurate characterization of Gaius’ complete DNA sequence, gene expression, and physical structure allows us to learn more about the genetic makeup and gene manipulation of bacteria.