Microbiology

Caitlin Murphy

Caitlin Murphy

Address: 3-315E BSB
Phone: (319) 335-7787
Email: caitlin-murphy@uiowa.edu

Mentor: Steven Clegg, PhD

Undergraduate Institution: University of Michigan

Research Description

Klebsiella pneumoniae is a common nosocomial pathogen of individuals with indwelling medical devices. The ability to form biofilms on these devices is often implicated in the establishment and persistence of Kpn infections. The first step in biofilm formation is attachment, which is mediated in part by type 3 fimbriae. Our focus in the laboratory is understanding the regulation of type 3 fimbrial expression and surface assembly. Thus far we have determined that fimbrial expression is affected by the intracellular concentrations of the bacterial second messenger, cyclic-di-GMP. Downstream from the structural operon are three genes that serve to regulate type 3 fimbrial expression: a phosphodiesterase that degrades cyclic-di-GMP, a putative DNA binding protein, and a cyclic-di-GMP binding protein. We are currently interested in understanding how these proteins work together to regulate the expression of the type 3 fimbrial operon.


Publication(s)

J.G. Johnson, C.N. Murphy, J. Sippy, T.J. Johnson, S. Clegg, Type 3 fimbriae and biofilm formation are regulated by the transcriptional regulators MrkHI in Klebsiella pneumoniae. Journal of Bacteriology 193, 3453 (Jul, 2011).