Microbiology

Jed Rasmussen

Jed Rasmussen

Address: 3-330 BSB
Phone: (319) 335-7794
Email: jed-rassmussen@uiowa.edu

Mentor: Bradley D. Jones, PhD

Undergraduate Institution: Utah State University

Research Description

Francisella tularensis, the causative agent of tularemia is a gram-negative facultative intracellular pathogen that can cause disease in humans with a dose small as 10 organisms. Due to the high infectivity and incidence of mortality, Francisella is considered a Class A select agent by the Centers for Disease Control and Prevention. While it is highly infectious, not much is known about the virulence factors of the organism. Of interest to my research is the role of outer surface components of Francisella in virulence. Through transposon screens and site-directed mutagenesis by our laboratory as well as others, mutants have been identified that are either null in both lipopolysaccharide (LPS) and capsule, deficient in O-antigen biosynthesis in LPS only but not capsule, or have normal LPS O-antigen but have alterations in capsule. To date the mutants discovered and characterized have revealed shared biosynthetic pathways between LPS and capsule. These “naked”, mutants null for both LPS and capsule, are serum sensitive whereas wild-type F. tularensis is serum resistant. Also a few of the naked mutants cause apoptosis

Publication(s)

Apicella MA, Post DM, Fowler AC, Jones BD, Rasmussen JA, Hunt JR, Imagawa S, Choudhury B, Inzana TJ, Maier TM, Frank DW, Zahrt TC, Chaloner K, Jennings MP, McLendon MK, Gibson BW. Identification, characterization and immunogenictiy of an O-antigen capsular polysaccharide of Francisella tularensis. PloS One. 2010 Jul 6;5(7):e11060.

Cardon ZG, Stark JM, Herron PM, Rasmussen JA. Plants carrying out hydraulic lift stimulate soil microbes and absorb more soil nitrogen. (Submitted)