Salt Inactivation as a Mechanistic Probe of Membrane‐Bound Chloroplast Coupling Factor 1

Nathan NELSON, Rachel BROZA

Research output: Contribution to journalArticlepeer-review

Abstract

Conditions are reported under which ATP protects membrane‐bound coupling factor 1 against sodium bromide inactivation. The presence of Mg2+ was found to be obligatory for this protection. ADP and GTP also protected the enzyme against salt inactivation but to a much smaller extent. Other nucleotides tested were ineffective. At low ATP concentrations ADP prevented the effect of ATP and modified the saturation curve for ATP from hyperbolic to sigmoidal. Treatment of chloroplasts with 0.4 M MgCI2 or 2 M LiCI resulted in inactivation of photophosphorylation. In contrast to NaBrdepleted particles the MgCl2 or LiCl‐depleted chloroplasts can be reconstituted by purified coupling factor 1. A binding site for Mg2+ and two different sites for ATP upon the coupling factor 1 are suggested to explain the mechanism of their protection against salt inactivation.

Original languageEnglish
Pages (from-to)203-208
Number of pages6
JournalEuropean Journal of Biochemistry
Volume69
Issue number1
DOIs
StatePublished - Oct 1976
Externally publishedYes

Fingerprint

Dive into the research topics of 'Salt Inactivation as a Mechanistic Probe of Membrane‐Bound Chloroplast Coupling Factor 1'. Together they form a unique fingerprint.

Cite this