Abstract
The superfamily of K+ transporters unites proteins from plants, fungi, bacteria, and archaea that translocate K+ and/or Na+ across membranes. These proteins are key components in osmotic regulation, pH homeostasis, and resistance to high salinity and dryness. The members of the superfamily are closely related to K+ channels such as KcsA but also show several striking differences that are attributed to their altered functions. This review highlights these functional differences, focusing on the bacterial superfamily members KtrB, TrkH, and KdpA. The functional variations within the family and comparison to MPM-type K+ channels are discussed in light of the recently solved structures of the Ktr and Trk systems.
Acknowledgments
I.H. acknowledges funding from the Deutsche Forschungsgemeinschaft (HA6322/2-1), the Cluster of Excellence Frankfurt, and the SFB 807 ‘Transport and Communication across Biological Membranes’. M.D., V.M., and C.S. acknowledge the Integrated research training group TRAM (SFB 807) for financial support.
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Articles in the same Issue
- Frontmatter
- Meeting Report
- Membrane Transport and Communication in Frankfurt: Speakers’ Summary – Highlights
- HIGHLIGHT: MEMBRANE TRANSPORT AND COMMUNICATION
- Structure, function, evolution, and application of bacterial Pnu-type vitamin transporters
- Team work at its best – TAPL and its two domains
- The volume-regulated anion channel is formed by LRRC8 heteromers – molecular identification and roles in membrane transport and physiology
- Extending native mass spectrometry approaches to integral membrane proteins
- Functional diversity of the superfamily of K+ transporters to meet various requirements
- The structure of Na+-translocating of NADH:ubiquinone oxidoreductase of Vibrio cholerae: implications on coupling between electron transfer and Na+ transport
- Hybrid rotors in F1Fo ATP synthases: subunit composition, distribution, and physiological significance
- Homeostatic control of biological membranes by dedicated lipid and membrane packing sensors
- The transporter associated with antigen processing: a key player in adaptive immunity
- The pseudo-atomic structure of an RND-type tripartite multidrug efflux pump
- The assembly and disassembly of the AcrAB-TolC three-component multidrug efflux pump
- A universal mechanism for transport and regulation of CPA sodium proton exchangers
- Biosynthesis of membrane dependent proteins in insect cell lysates: identification of limiting parameters for folding and processing
- Fluorescence and excited state dynamics of the deprotonated Schiff base retinal in proteorhodopsin
- Regulatory role of charged clusters in the N-terminal domain of BetP from Corynebacterium glutamicum
- The contribution of methionine to the stability of the Escherichia coli MetNIQ ABC transporter-substrate binding protein complex
- The ABC exporter MsbA probed by solid state NMR – challenges and opportunities
- Functional properties of LptA and LptD in Anabaena sp. PCC 7120
Articles in the same Issue
- Frontmatter
- Meeting Report
- Membrane Transport and Communication in Frankfurt: Speakers’ Summary – Highlights
- HIGHLIGHT: MEMBRANE TRANSPORT AND COMMUNICATION
- Structure, function, evolution, and application of bacterial Pnu-type vitamin transporters
- Team work at its best – TAPL and its two domains
- The volume-regulated anion channel is formed by LRRC8 heteromers – molecular identification and roles in membrane transport and physiology
- Extending native mass spectrometry approaches to integral membrane proteins
- Functional diversity of the superfamily of K+ transporters to meet various requirements
- The structure of Na+-translocating of NADH:ubiquinone oxidoreductase of Vibrio cholerae: implications on coupling between electron transfer and Na+ transport
- Hybrid rotors in F1Fo ATP synthases: subunit composition, distribution, and physiological significance
- Homeostatic control of biological membranes by dedicated lipid and membrane packing sensors
- The transporter associated with antigen processing: a key player in adaptive immunity
- The pseudo-atomic structure of an RND-type tripartite multidrug efflux pump
- The assembly and disassembly of the AcrAB-TolC three-component multidrug efflux pump
- A universal mechanism for transport and regulation of CPA sodium proton exchangers
- Biosynthesis of membrane dependent proteins in insect cell lysates: identification of limiting parameters for folding and processing
- Fluorescence and excited state dynamics of the deprotonated Schiff base retinal in proteorhodopsin
- Regulatory role of charged clusters in the N-terminal domain of BetP from Corynebacterium glutamicum
- The contribution of methionine to the stability of the Escherichia coli MetNIQ ABC transporter-substrate binding protein complex
- The ABC exporter MsbA probed by solid state NMR – challenges and opportunities
- Functional properties of LptA and LptD in Anabaena sp. PCC 7120