SystemsAlexa Price-Whelan,a Chun Kit Poon,a Meredith A. Benson,b
SystemsAlexa Price-Whelan,a Chun Kit Poon,a Meredith A. Benson,b Tess T. Eidem,c Christelle M. Roux,c Jeffrey M. Boyd,d Paul M. Dunman,c Victor J. Torres,b Terry A. KrulwichaDepartment of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York, USAa; Division of Microbiology, New York University College of Medicine, New York, New York, USAb; Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USAc; Division of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USAdABSTRACT Staphylococcus aureus exhibits an unusually RGS4 MedChemExpress higher level of osmotolerance and Na tolerance, properties that supportsurvival in many host niches and in preserved foods. The genetic basis of those traits is just not effectively understood. We compared the transcriptional profiles of S. aureus grown in complicated medium with and devoid of 2 M NaCl. The stimulon for growth in highosmolality media and Na integrated genes RelB Formulation involved in uptake of K , other compatible solutes, sialic acid, and sugars; capsule biosynthesis; and amino acid and central metabolism. Quantitative PCR analysis revealed that the loci responded differently from every other to high osmolality imposed by elevated NaCl versus sucrose. High-affinity K uptake (kdp) genes and capsule biosynthesis (cap5) genes essential the two-component program KdpDE for complete induction by osmotic pressure, with kdpA induced more by NaCl and cap5B induced a lot more by sucrose. Focusing on K importers, we identified three S. aureus genes belonging for the lower-affinity Trk/Ktr loved ones that encode two membrane proteins (KtrB and KtrD) and a single accessory protein (KtrC). In the absence of osmotic anxiety, the ktr gene transcripts had been a great deal extra abundant than the kdpA transcript. Disruption of S. aureus kdpA brought on a development defect under low-K conditions, disruption of ktrC resulted within a important defect in 2 M NaCl, and also a ktrC kdpA double mutant exhibited both phenotypes. Protective effects of S. aureus Ktr transporters at elevated NaCl are constant with previous indications that each Na and osmolality challenges are mitigated by the maintenance of a higher cytoplasmic K concentration.Value There’s basic agreement that the osmotolerance and Na tolerance of Staphylococcus aureus are unusually highfor a nonhalophile and help its capacity for human colonization, pathogenesis, and growth in meals. Nonetheless, the molecular basis for these properties is not well defined. The genome-wide response of S. aureus to a high concentration, 2 M, of NaCl revealed the upregulation of anticipated genes, which include those for transporters of compatible solutes that are widely implicated in supporting osmotolerance. A high-affinity potassium uptake program, KdpFABC, was upregulated, though it generally plays a physiological role beneath pretty low K conditions. At greater K concentrations, a lower-affinity and more hugely expressed style of K transporter technique, Ktr transporters, was shown to play a important part in higher Na tolerance. This study illustrates the value with the K status of the cell for tolerance of Na by S. aureus and underscores the significance of monovalent cation cycles within this pathogen.Received 31 May perhaps 2013 Accepted 24 July 2013 Published 20 August 2013 Citation Price-Whelan A, Poon CK, Benson MA, Eidem TT, Roux CM, Boyd JM, Dunman PM, Torres VJ, Krulwich TA. 2013. Transcriptional profiling of Staphylococcus aureus for the duration of g.