Effects of polyamines on partial reactions of membrane (Na+ + K+)-ATPase

Gregory Quarfoth, Khalil Ahmed, Donald Foster

Research output: Contribution to journalArticlepeer-review

18 Scopus citations

Abstract

Spermine and spermidine inhibit the (Na+ + K+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) reaction so that the effect increases as the ionic content due to Na+ and K+ in the reaction is reduced. Several other amines inhibit (Na+ + K+)-ATPase to varying degress and methylglyoxal-bis(guanylhydrazone) was the most potent inhibitor among those tested. The inhibition by polyamines of the ATPase is uncompetitive with respect to Mg2+ and ATP activation of the reaction. Various naturally occurring polyamines and other amines inhibited Na+ activation of (Na+ + K+)-ATPase as well as Na+-dependent phosphoenzyme formation in an apparently competitive manner with respect to Na+. Likewise, K+-activation of (Na+ + K+)-ATPase as well as K+-p-nitrophenyl phosphatase was inhibited in an apparently competitive manner with respect to K+. Both the cation charge and structure (e.g., aliphatic chain length) may contribute to the inhibitory effects of the amines; however, Na+ sites appear to be more sensitive to cation charge than the aliphatic chain length of the amine, whereas the opposite appears to be true for K+ sites. The results do not indicate a specific effect of polyamines on (Na+ + K+)-ATPase or its partial reactions.

Original languageEnglish (US)
Pages (from-to)580-590
Number of pages11
JournalBBA - Enzymology
Volume526
Issue number2
DOIs
StatePublished - Oct 12 1978

Fingerprint Dive into the research topics of 'Effects of polyamines on partial reactions of membrane (Na<sup>+</sup> + K<sup>+</sup>)-ATPase'. Together they form a unique fingerprint.

Cite this