Linked Life Data

16666731

Source:http://linkedlifedata.com/resource/pubmed/id/16666731

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2010-6-29
pubmed:abstractText
The nature of Cu(2+) inhibition of photosystem II (PSII) photochemistry in pea (Pisum sativum L.) thylakoids was investigated monitoring Hill activity and light emission properties of photosystem II. In Cu(2+)-inhibited thylakoids, diphenyl carbazide addition does not relieve the loss of Hill activity. The maximum yield of fluorescence induction restored by hydroxylamine in Tris-inactivated thylakoids is markedly reduced by Cu(2+). This suggests that Cu(2+) does not act on the donor side of PSII but on the reaction center of PSII or on components beyond. Thermoluminescence and delayed luminescence studies show that charge recombination between the positively charged intermediate in water oxidation cycle (S(2)) and negatively charged primary quinone acceptor of pSII (Q(A) (-)) is largely unaffected by Cu(2+). The S(2)Q(B) (-) charge recombination, however, is drastically inhibited which parallels the loss of Hill activity. This indicates that Cu(2+) inhibits photosystem II photochemistry primarily affecting the function of the secondary quinone electron acceptor, Q(B). We suggest that Cu(2+) does not block electron flow between the primary and secondary quinone acceptor but modifies the Q(B) site in such a way that it becomes unsuitable for further photosystem II photochemistry.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
May
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
175-9
pubmed:dateRevised
2010-9-14
pubmed:year
1989
pubmed:articleTitle
Copper Toxicity Affects Photosystem II Electron Transport at the Secondary Quinone Acceptor, Q(B).
pubmed:affiliation
Institute of Plant Physiology, P. O. Box 521, H-6701, Szeged, Hungary.
pubmed:publicationType
Journal Article