Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Mar 15;404(7):715-725.
doi: 10.1515/hsz-2022-0337. Print 2023 Jun 27.

Membrane-anchored substrate binding proteins are deployed in secondary TAXI transporters

Anja Roden  1 , Melanie K Engelin  1 , Klaas M Pos  1 , Eric R Geertsma  1   2
Affiliations
Free article

Membrane-anchored substrate binding proteins are deployed in secondary TAXI transporters

Anja Roden et al. Biol Chem. .
Free article

Abstract

Substrate-binding proteins (SBPs) are part of solute transport systems and serve to increase substrate affinity and uptake rates. In contrast to primary transport systems, the mechanism of SBP-dependent secondary transport is not well understood. Functional studies have thus far focused on Na+-coupled Tripartite ATP-independent periplasmic (TRAP) transporters for sialic acid. Herein, we report the in vitro functional characterization of TAXIPm-PQM from the human pathogen Proteus mirabilis. TAXIPm-PQM belongs to a TRAP-subfamily using a different type of SBP, designated TRAP-associated extracytoplasmic immunogenic (TAXI) protein. TAXIPm-PQM catalyzes proton-dependent α-ketoglutarate symport and its SBP is an essential component of the transport mechanism. Importantly, TAXIPm-PQM represents the first functionally characterized SBP-dependent secondary transporter that does not rely on a soluble SBP, but uses a membrane-anchored SBP instead.

Keywords: TRAP-associated extracytoplasmic immunogenic (TAXI); membrane anchor; substrate-binding protein-dependent secondary transport; tripartite ATP-independent periplasmic (TRAP).

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

References

    1. Albers, S.V., Elferink, M.G., Charlebois, R.L., Sensen, C.W., Driessen, A.J., and Konings, W.N. (1999). Glucose transport in the extremely thermoacidophilic Sulfolobus solfataricus involves a high-affinity membrane-integrated binding protein. J. Bacteriol. 181: 4285–4291, https://doi.org/10.1128/jb.181.14.4285-4291.1999 . - DOI
    1. Bergeron, M.J., Clemencon, B., Hediger, M.A., and Markovich, D. (2013). SLC13 family of Na+-coupled di-and tri-carboxylate/sulfate transporters. Mol. Aspect. Med. 34: 299–312, https://doi.org/10.1016/j.mam.2012.12.001 . - DOI - PubMed
    1. Bosdriesz, E., Magnusdottir, S., Bruggeman, F.J., Teusink, B., and Molenaar, D. (2015). Binding proteins enhance specific uptake rate by increasing the substrate-transporter encounter rate. FEBS J. 282: 2394–2407, https://doi.org/10.1111/febs.13289 . - DOI - PubMed
    1. Brautigam, C.A., Deka, R.K., Schuck, P., Tomchick, D.R., and Norgard, M.V. (2012). Structural and thermodynamic characterization of the interaction between two periplasmic Treponema pallidum lipoproteins that are components of a TPR-protein-associated TRAP transporter (TPAT). J. Mol. Biol. 420: 70–86, https://doi.org/10.1016/j.jmb.2012.04.001 . - DOI - PubMed - PMC
    1. Brautigam, C.A., Zhao, H., Vargas, C., Keller, S., and Schuck, P. (2016). Integration and global analysis of isothermal titration calorimetry data for studying macromolecular interactions. Nat. Protoc. 11: 882–894, https://doi.org/10.1038/nprot.2016.044 . - DOI - PubMed - PMC

Publication types

MeSH terms

LinkOut - more resources