Linked Life Data

10350477

Source:http://linkedlifedata.com/resource/pubmed/id/10350477

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1999-6-9
pubmed:abstractText
Trimeric (bT) and monomeric (bM) light-harvesting complex II (LHCII) with a chlorophyll a/b ratio of 0.03 were reconstituted from the apoprotein overexpressed in Escherichia coli. Chlorophyll/xanthophyll and chlorophyll/protein ratios of bT complexes and 'native' LHCII are rather similar, namely, 0.28 vs 0. 27 and 10.5 +/- 1.5 vs 12, respectively, indicating the replacement of most chlorophyll a molecules with chlorophyll b, leaving one chlorophyll a per trimeric complex. The LD spectrum of the bT complexes strongly suggests that the chlorophyll b molecules adopt orientations similar to those of the chlorophylls a that they replace. The circular dichroism (CD) spectra of bM and bT complexes indicate structural arrangements resembling those of 'native' LHCII. Thermolysin digestion patterns demonstrate that bT complexes are folded and organized like 'native' trimeric LHCII. Surprisingly, in the bT complexes at 77 K, half of the excitations that are created on either chlorophyll b or xanthophyll are transferred to chlorophyll a. No or very limited triplet transfer from chlorophyll b to xanthophyll appears to take place. However, the efficiency of triplet transfer from chlorophyll a to xanthophyll is close to 100%, even higher than in 'native' LHCII at 77 K. It is concluded from the triplet-minus-singlet and CD results that the single chlorophyll a molecule that on the average is present in each bT complex binds preferably next to a xanthophyll molecule at the interface between the monomers.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6587-96
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Decreasing the chlorophyll a/b ratio in reconstituted LHCII: structural and functional consequences.
pubmed:affiliation
Division of Physics and Astronomy, Institute for Condensed Matter Physics and Spectroscopy, Vrije Universiteit Amsterdam, The Netherlands. foske@nat.vu.nl
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't