Sandra K. Armstrong, Ph.D.

Associate Professor

Department of Microbiology

University of Missouri-Columbia, 1986, Ph.D.

armst018@umn.edu

612-625-6947 office
612-624-5177 lab

 

Research Interests:

Iron Acquisition in Bordetella species

Nearly all organisms require nutritive iron and its assimilation is essential for invading pathogenic bacteria to establish infection in the iron-limiting environment of the host. Research in my laboratory is centered on iron retrieval by members of the bacterial genus Bordetella.

Bordetella pertussis, Bordetella bronchiseptica and Bordetella parapertussis are mammalian respiratory pathogens that are highly genetically-related Gram-negative members of the family Alcaligenaceae. B. pertussis, the agent of whooping cough (pertussis), is an obligate human pathogen. B. parapertussis causes respiratory infections in humans and sheep, and B. bronchiseptica infects nonhuman mammals, causing kennel cough in dogs, atrophic rhinitis in swine and snuffles in rabbits. These Bordetella species obtain iron supplied by their native iron-chelating siderophore, alcaligin, as well as siderophores produced by other microbial species (termed xenosiderophores) and from host iron containing compounds including heme. These iron retrieval systems are expressed when the bacteria are starved for iron and expression is further activated by cognate transcriptional regulators that respond to the presence of the specific iron compound. Recent studies also indicate that these bacteria can utilize host neuroendocrine hormones, such as norepinephrine, for iron retrieval. Our studies are aimed at understanding the processes governing the expression of different Bordetella iron acquisition systems in the host during the course of infection.

Selected Recent Publications:

  • Brickman, T.J., Hanawa T., Anderson M.T., Suhadolc, R.J. and S.K. Armstrong. 2008. Differential expression of Bordetella pertussis iron transport system genes during infection. Mol. Microbiol. 70:3-14.
  • Anderson, M.T. and S.K. Armstrong. 2008. Norepinephrine mediates acquisition of transferrin-iron in Bordetella bronchiseptica. J. Bacteriol. 190:3940-3947.
  • Brickman, T.J. and S.K. Armstrong. 2007. Impact of alcaligin siderophore utilization on in vivo growth of Bordetella pertussis. Infect. Immun. 75:5305-5312.
  • Brickman, T.J., M.T. Anderson, and S.K. Armstrong. 2007. Bordetella iron transport and virulence. BioMetals. 20:303-322.
  • Anderson, M.T., Armstrong, S.K. 2006. The Bordetella bfe system: growth and transcriptional response to siderophores, catechols, and neuroendocrine catecholamines. J Bacteriol. 188(16):5731-40.
  • Brickman, T.J., Vanderpool, C.K., Armstrong, S.K. 2006. Heme transport contributes to in vivo fitness of Bordetella pertussis during primary infection in mice. Infect Immun. 74(3):1741-4.
  • Brickman, T.J., Armstrong, S.K. 2005. Bordetella AlcS transporter functions in alcaligin siderophore export and is central to inducer sensing in positive regulation of alcaligin system gene expression. J Bacteriol. 2005 Jun;187(11):3650-61.

Last modified on: October 3, 2008