Adaptation to the host environment: regulation of the SPI1 type III secretion system in Salmonella enterica serovar Typhimurium Jeremy R Ellermeier1 and James M Slauch Addresses Department of Microbiology, University of Illinois, B103 Chemical and Life Sciences Laboratory, 601 S Goodwin Avenue, Urbana, IL 61801, USA College of Medicine, University of Illinois, Urbana, IL 61801, USA Corresponding author: Slauch, James M (slauch@uiuc.edu) Current Opinion in Microbiology 2007, 10:24–29 This review comes from a themed issue on Host-microbe interactions: bacteria Edited by Pamela Small and Gisou van der Goot Available online 5th January 2007 1369-5274/$ – see front matter # 2006 Elsevier Ltd. All rights reserved. DOI 10.1016/j.mib.2006.12.002