Encyclopedia of Biophysics

Living Edition
| Editors: Gordon Roberts, Anthony Watts, European Biophysical Societies

Structural Aspects of UapA the H+-Xanthine/Uric Acid Transporter from Aspergillus nidulans

  • Yilmaz AlguelEmail author
  • Sotiris Amillis
  • Euan Pyle
  • Argyris Politis
  • Emmanuel Mikros
  • Alexander D. Cameron
  • George Diallinas
  • Bernadette Byrne
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-35943-9_10089-1


UapA is a member of the nucleobase ascorbate transporter (NAT) family, also known as the nucleobase-cation-symport-2 (NCS-2) family, designated A.2.40 in the Transporter Classification Database (TCDB) (Saier et al. 2006, 2009, 2016). See also Kourkoulou et al., Nucleobase-Ascorbate-Transporter (NAT) Family this volume. UapA is a H+-dependent symporter responsible for uptake of the purines, xanthine and uric acid. The wild-type protein contains 574 residues (Diallinas and Scazzocchio 1989). A modified construct containing a single point mutation (G411V) and lacking the N-terminal 11 amino acids termed UapAG411VΔ1−11 (Leung et al. 2013) was used for recombinant expression, isolation, crystallization, and structure determination. This protein binds xanthine (Leung et al. 2013) and effectively traffics to the membrane but is transport inactive (Koukaki et al. 2005). The purified UapAG411VΔ1−11 protein is sufficiently stable for crystallization (Alguel et al. 2016) and analysis...

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Copyright information

© European Biophysical Societies’ Association (EBSA) 2018

Authors and Affiliations

  • Yilmaz Alguel
    • 1
    Email author
  • Sotiris Amillis
    • 2
  • Euan Pyle
    • 1
    • 3
  • Argyris Politis
    • 3
  • Emmanuel Mikros
    • 4
  • Alexander D. Cameron
    • 5
  • George Diallinas
    • 2
  • Bernadette Byrne
    • 1
  1. 1.Department of Life SciencesImperial College LondonLondonUK
  2. 2.Department of BiologyNational and Kapodistrian University of AthensAthensGreece
  3. 3.Department of ChemistryKing’s College LondonLondonUK
  4. 4.Faculty of PharmacyUniversity of AthensAthensGreece
  5. 5.School of Life SciencesUniversity of WarwickCoventryUK

Section editors and affiliations

  • Peter J. F. Henderson
    • 1
  1. 1.Astbury Centre for Structural Molecular Biology, Institute of Membrane and Systems BiologyUniversity of LeedsLeedsUK