title: The Staphylococcus aureus KdpDE two-component system couples extracellular K+ sensing and Agr signaling to infection programming.
abstract: The Kdp system is widely distributed among bacteria. In Escherichia coli, the Kdp-ATPase is a high-affinity K+ uptake system and its expression is activated by the KdpDE two-component system in response to K+ limitation or salt stress. However, information about the role of this system in many bacteria still remains obscure. Here we demonstrate that KdpFABC in Staphylococcus aureus is not a major K+ transporter and that the main function of KdpDE is not associated with K+ transport but that instead it regulates transcription for a series of virulence factors through sensing external K+ concentrations, indicating that this bacterium might modulate its infectious status through sensing specific external K+ stimuli in different environments. Our results further reveal that S. aureus KdpDE is upregulated by the Agr/RNAIII system, which suggests that KdpDE may be an important virulence regulator coordinating the external K+ sensing and Agr signaling during pathogenesis in this bacterium.
authors.affiliation: Department of Microbiology and Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China. xueting@mail.ustc.edu.cn
authors.forename: Ting
authors.initials: T
authors.lastname: Xue
authors.forename: Yibo
authors.initials: Y
authors.lastname: You
authors.forename: De
authors.initials: D
authors.lastname: Hong
authors.forename: Haipeng
authors.initials: H
authors.lastname: Sun
authors.forename: Baolin
authors.initials: B
authors.lastname: Sun
mesh_terms: D001426:Bacterial Proteins / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D005798:Genes, Bacterial / Q000502:physiology; D006801:Humans; D011188:Potassium / Q000502:physiology*; D011401:Promoter Regions, Genetic / Q000502:physiology; D012329:RNA, Bacterial / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology; D013203:Staphylococcal Infections / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000502:physiology*; D015534:Trans-Activators / Q000502:physiology*; D014158:Transcription, Genetic / Q000235:genetics / Q000502:physiology; D037521:Virulence Factors / Q000502:physiology
chemical_list: C095698:Agr protein, Staphylococcus aureus; D001426:Bacterial Proteins; D012329:RNA, Bacterial; C096035:RNAIII, Staphylococcus aureus; D015534:Trans-Activators; D037521:Virulence Factors; D011188:Potassium