title: Development and testing of improved suicide functions for biological containment of bacteria.
abstract: We have developed very efficient suicide functions for biological containment based on the lethal Escherichia coli relF gene. The suicide functions are placed in duplicate within a plasmid and arranged to prevent inactivation by deletion, recombination, and insertional inactivation. The efficiency of this concept was tested in a plasmid containment system that prevents transfer of plasmids to wild-type bacteria. Protection against plasmid transfer was assayed in test tubes and in rat intestine. Protection was efficient and refractory to inactivation by mutation and transposons. The efficiency of the suicide system was also tested in soil and seawater. We show that unprecedented suicide efficiency can be achieved in soil and seawater after suicide induction by IPTG (isopropyl-beta-D-thiogalactopyranoside). More than 7 orders of magnitude reduction in suicide bacteria was achieved.
authors.affiliation: Center for Environmental Diagnostics and Bioremediation, University of West Florida 32561.
authors.forename: S
authors.initials: S
authors.lastname: Knudsen
authors.forename: P
authors.initials: P
authors.lastname: Saadbye
authors.forename: L H
authors.initials: LH
authors.lastname: Hansen
authors.forename: A
authors.initials: A
authors.lastname: Collier
authors.forename: B L
authors.initials: BL
authors.lastname: Jacobsen
authors.forename: J
authors.initials: J
authors.lastname: Schlundt
authors.forename: O H
authors.initials: OH
authors.lastname: Karlström
mesh_terms: D000818:Animals; D003264:Containment of Biohazards / Q000379:methods*; D004926:Escherichia coli / Q000235:genetics* / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D005798:Genes, Bacterial / Q000235:genetics* / Q000502:physiology; D005822:Genetic Vectors / Q000235:genetics*; D005856:Germ-Free Life; D007422:Intestines / Q000382:microbiology; D007544:Isopropyl Thiogalactoside / Q000494:pharmacology; D051381:Rats; D012623:Seawater; D012988:Soil Microbiology; D014169:Transformation, Bacterial; D014871:Water Microbiology
chemical_list: D007544:Isopropyl Thiogalactoside