Linked Life Data

12646275

Source:http://linkedlifedata.com/resource/pubmed/id/12646275

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2003-3-20
pubmed:abstractText
Free Mg(2+) in chloroplasts may contribute to the regulation of photosynthetic enzymes, but adequate methodology for the determination of free Mg(2+) concentration ([Mg(2+)]) in chloroplasts has been lacking. We measured internal chloroplast [Mg(2+)] by using a Mg-sensitive fluorescent indicator, mag-fura-2. In intact, dark-kept spinach chloroplasts, internal [Mg(2+)] was estimated to be 0.50 mM, and illumination caused an increase in [Mg(2+)] to 2.0mM in the stroma. The light-induced increase in [Mg(2+)] was inhibited by a blocker of driven electron transport and uncouplers. The K(+)-specific ionophore valinomycin inhibited the [Mg(2+)] increase in the absence of external K(+), and addition of KCl restored the [Mg(2+)] increase. NH(4)Cl, which induces stromal alkalinization, enhanced the [Mg(2+)] increase. A Ca(2+)-channel blocker, ruthenium red, inhibited the [Mg(2+)] increase, but LaCl(3) had no effect. These results indicate that stromal alkalinization is essential for light-induced increase in [Mg(2+)]. This system for measuring internal chloroplast [Mg(2+)] might provide a suitable system for assay of Mg(2+) transport activity of chloroplast membranes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
412
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
126-32
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Light-induced increase in free Mg2+ concentration in spinach chloroplasts: measurement of free Mg2+ by using a fluorescent probe and necessity of stromal alkalinization.
pubmed:affiliation
Graduate School of Agriculture, The Prefecture University of Kyoto, Kyoto 606-8522, Japan. ishijima@kpu.ac.jp
pubmed:publicationType
Journal Article