GNP1, the high-affinity glutamine permease of S. cerevisiae

Curr Genet. 1996 Jul 31;30(2):107-14. doi: 10.1007/s002940050108.


Glutamine uptake in S. cerevisiae is mediated by at least three transporters: high- and low-affinity glutamine permeases and the general amino-acid permease. We have isolated the gene encoding the high-affinity glutamine permease and named it GNP1. The amino-acid sequence of GNP1, and its hydropathy profile of 12 transmembrane domains, closely resemble those of known amino-acid permeases. The Km of GNP1 for glutamine uptake was determined to be 0.59 mM. Cells lacking GNP1 exhibit reduced levels of glutamine transport, and are resistant to a toxic analog of glutamine, L-glutamic acid gamma-monohydroxamate. Unlike other amino-acid permeases, whose expression is nitrogen-source limited, GNP1 is expressed on both rich and poor nitrogen sources.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Amino Acid Transport Systems, Basic*
  • Amino Acid Transport Systems, Neutral
  • Glutamine / metabolism
  • Membrane Transport Proteins / genetics*
  • Membrane Transport Proteins / metabolism
  • Molecular Sequence Data
  • Nitrogen / metabolism
  • Saccharomyces cerevisiae / enzymology*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae Proteins
  • Sequence Homology, Amino Acid


  • AGP1 protein, S cerevisiae
  • Amino Acid Transport Systems, Basic
  • Amino Acid Transport Systems, Neutral
  • Membrane Transport Proteins
  • Saccharomyces cerevisiae Proteins
  • Glutamine
  • glutamine permease
  • Nitrogen

Associated data

  • GENBANK/U21643