title: FlpS, the FNR-Like Protein of Streptococcus suis Is an Essential, Oxygen-Sensing Activator of the Arginine Deiminase System.
abstract: Streptococcus (S.) suis is a zoonotic pathogen causing septicemia and meningitis in pigs and humans. During infection S. suis must metabolically adapt to extremely diverse environments of the host. CcpA and the FNR family of bacterial transcriptional regulators are important for metabolic gene regulation in various bacteria. The role of CcpA in S. suis is well defined, but the function of the FNR-like protein of S. suis, FlpS, is yet unknown. Transcriptome analyses of wild-type S. suis and a flpS mutant strain suggested that FlpS is involved in the regulation of the central carbon, arginine degradation and nucleotide metabolism. However, isotopologue profiling revealed no substantial changes in the core carbon and amino acid de novo biosynthesis. FlpS was essential for the induction of the arcABC operon of the arginine degrading pathway under aerobic and anaerobic conditions. The arcABC-inducing activity of FlpS could be associated with the level of free oxygen in the culture medium. FlpS was necessary for arcABC-dependent intracellular bacterial survival but redundant in a mice infection model. Based on these results, we propose that the core function of S. suis FlpS is the oxygen-dependent activation of the arginine deiminase system.
authors.affiliation: Institute for Microbiology, University of Veterinary Medicine Hannover, 30173 Hannover, Germany. joerg.willenborg@tiho-hannover.de.
authors.forename: Jörg
authors.initials: J
authors.lastname: Willenborg
authors.affiliation: Institute for Microbiology, University of Veterinary Medicine Hannover, 30173 Hannover, Germany. anna.koczula@tiho-hannover.de.
authors.forename: Anna
authors.initials: A
authors.lastname: Koczula
authors.affiliation: Institute for Microbiology, University of Veterinary Medicine Hannover, 30173 Hannover, Germany. marcus.fulde@fu-berlin.de.
authors.forename: Marcus
authors.initials: M
authors.lastname: Fulde
authors.affiliation: Animal Sciences Group (ASG) of Wageningen UR, 8219 PH Lelystad, The Netherlands. Astrid.degreeff@wur.nl.
authors.forename: Astrid
authors.initials: A
authors.lastname: de Greeff
authors.affiliation: Institute for Pathology, University of Veterinary Medicine Hannover, 30173 Hannover, Germany. andreas.beineke@tiho-hannover.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Beineke
authors.affiliation: Lehrstuhl f&#252;r Biochemie, Technische Universit&#228;t M&#252;nchen, 85748 Garching, Germany. wolfgang.eisenreich@mytum.de.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Eisenreich
authors.affiliation: Lehrstuhl f&#252;r Biochemie, Technische Universit&#228;t M&#252;nchen, 85748 Garching, Germany. claudia.huber@mytum.de.
authors.forename: Claudia
authors.initials: C
authors.lastname: Huber
authors.affiliation: Institute for Microbiology, University of Veterinary Medicine Hannover, 30173 Hannover, Germany. maren.seitz@tiho-hannover.de.
authors.forename: Maren
authors.initials: M
authors.lastname: Seitz
authors.affiliation: Institute for Microbiology, University of Veterinary Medicine Hannover, 30173 Hannover, Germany. peter.valentin@tiho-hannover.de.
authors.forename: Peter
authors.initials: P
authors.lastname: Valentin-Weigand
authors.affiliation: Institute for Microbiology, University of Veterinary Medicine Hannover, 30173 Hannover, Germany. ralph.goethe@tiho-hannover.de.
authors.forename: Ralph
authors.initials: R
authors.lastname: Goethe
keywords: FNR-like protein; Streptococcus suis; arginine deiminase system