These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Arginine uptake through a novel cationic amino acid:K+ symporter, System R+, in brush border membrane vesicles from larval Manduca sexta midgut.
    Author: Liu Z, Harvey WR.
    Journal: Biochim Biophys Acta; 1996 Jun 13; 1282(1):25-31. PubMed ID: 8679656.
    Abstract:
    A concentrative uptake of arginine into brush border membrane vesicles (BBMV) from the midgut of Manduca sexta larvae was driven by an inwardly directed K+ gradient. The pH-dependence of the initial rate of arginine uptake between pH 7 and 10.5 paralleled the titration curve of the amino acid, suggesting that cationic arginine is the principal ionic form that is transported. In the presence of K+, at pH 7.4, arginine uptake was cis-inhibited and trans-stimulated by arginine and lysine but not by any other naturally occurring amino acids; it was also cis-inhibited by homoarginine and ornithine. Taken together, these data argue that arginine, lysine and their analogues share a cationic amino acid:K+ symporter (cotransporter), which we will designate as System R+. This novel symporter has a substrate spectrum similar to that of the uniporter, System y+, in that it accepts arginine+, lysine+, homoarginine+ and ornithine+ and rejects histidine. However, it differs from y+ in that it is cation-dependent and is almost inactive at pH 5.5.
    [Abstract] [Full Text] [Related] [New Search]