Lauren Johnson, Weber State University
Microbiology
Bacteriophages in aquatic environments play a significant role in bacteria population control, as well as recycling nutrients. The bacterial genus Halomonas is commonly found in the Great Salt Lake (GSL), but very little is known concerning its population dynamics. This euryhalophilic genus is highly versatile concerning its ability to grow in a wide range of substrates and environmental conditions including salt concentration. To better understand GSL microbial ecology, seven strains of Halomonas were isolated from the GSL and identified using 16S rRNA. Samples of South Arm GSL water were filtered twice through a 0.2 m filter, and tested against these Halomonas strains using soft agar overlays to detect Halomonas phage. Three strains exhibited plaque formation indicating the presence of phage. Halomonas phage isolates produced very small plaques, sometimes barely visible. Individual phages were isolated by vortexing agar plugs taken from single plaques in sterile saline then filtering through a 0.2 m filter. From host range streak plates, a single phage isolate (LJ17) appears to infect 4 closely related Halomonas strains. Electron micrographs of LJ17 phage indicate it has a small icosahedral head and perhaps a very short tail. There also appears to be a satellite phage that may be associated with LJ17. There are no reports of Halomonas phage isolated from the Great Salt Lake (GSL), although there are phages found for marine Halomonas strains. Successful isolation and characterization of novel GSL Halomonas phage, besides being critical for development of host/phage models, will also allow studies of GSL microbial ecology.